The time-course linkage between hemolysis, redox, and metabolic parameters during red blood cell storage with or without uric acid and ascorbic acid supplementation

Oxidative phenomena are considered to lie at the root of the accelerated senescence observed in red blood cells (RBCs) stored under standard blood bank conditions. It was recently shown that the addition of uric (UA) and/or ascorbic acid (AA) to the preservative medium beneficially impacts the storability features of RBCs related to the handling of pro-oxidant triggers. This study constitutes the next step, aiming to examine the links between hemolysis, redox, and metabolic parameters in control and supplemented RBC units of different storage times. For this purpose, a paired correlation analysis of physiological and metabolism parameters was performed between early, middle, and late storage in each subgroup. Strong and repeated correlations were observed throughout storage in most hemolysis parameters, as well as in reactive oxygen species (ROS) and lipid peroxidation, suggesting that these features constitute donor-signatures, unaffected by the diverse storage solutions. Moreover, during storage, a general “dialogue” was observed between parameters of the same category (e.g., cell fragilities and hemolysis or lipid peroxidation and ROS), highlighting their interdependence. In all groups, extracellular antioxidant capacity, proteasomal activity, and glutathione precursors of preceding time points anticorrelated with oxidative stress lesions of upcoming ones. In the case of supplemented units, factors responsible for glutathione synthesis varied proportionally to the levels of glutathione itself. The current findings support that UA and AA addition reroutes the metabolism to induce glutathione production, and additionally provide mechanistic insight and footing to examine novel storage optimization strategies

Management of asthma in childhood: study protocol of a systematic evidence update by the Paediatric Asthma in Real Life (PeARL) Think Tank

IntroductionClinical recommendations for childhood asthma are often based on data extrapolated from studies conducted in adults, despite significant differences in mechanisms and response to treatments. The Paediatric Asthma in Real Life (PeARL) Think Tank aspires to develop recommendations based on the best available evidence from studies in children. An overview of systematic reviews (SRs) on paediatric asthma maintenance management and an SR of treatments for acute asthma attacks in children, requiring an emergency presentation with/without hospital admission will be conducted.Methods and analysisStandard methodology recommended by Cochrane will be followed. Maintenance pharmacotherapy of childhood asthma will be evaluated in an overview of SRs published after 2005 and including clinical trials or real-life studies. For evaluating pharmacotherapy of acute asthma attacks leading to an emergency presentation with/without hospital admission, we opted to conduct de novo synthesis in the absence of adequate up-to-date published SRs. For the SR of acute asthma pharmacotherapy, we will consider eligible SRs, clinical trials or real-life studies without time restrictions. Our evidence updates will be based on broad searches of Pubmed/Medline and the Cochrane Library. We will use A MeaSurement Tool to Assess systematic Reviews, V.2, Cochrane risk of bias 2 and REal Life EVidence AssessmeNt Tool to evaluate the methodological quality of SRs, controlled clinical trials and real-life studies, respectively. Next, we will further assess interventions for acute severe asthma attacks with positive clinical results in meta-analyses. We will include both controlled clinical trials and observational studies and will assess their quality using the previously mentioned tools. We will employ random effect models for conducting meta-analyses, and Grading of Recommendations Assessment, Development and Evaluation methodology to assess certainty in the body of evidence.Ethics and disseminationEthics approval is not required for SRs. Our findings will be published in peer reviewed journals and will inform clinical recommendations being developed by the PeARL Think Tank.PROSPERO registration numbers CRD42020132990, CRD42020171624.</p

Blood Cell-Derived Microvesicles in Hematological Diseases and beyond

Microvesicles or ectosomes represent a major type of extracellular vesicles that are formed by outward budding of the plasma membrane. Typically, they are bigger than exosomes but smaller than apoptotic vesicles, although they may overlap with both in size and content. Their release by cells is a means to dispose redundant, damaged, or dangerous material; to repair membrane lesions; and, primarily, to mediate intercellular communication. By participating in these vital activities, microvesicles may impact a wide array of cell processes and, consequently, changes in their concentration or components have been associated with several pathologies. Of note, microvesicles released by leukocytes, red blood cells, and platelets, which constitute the vast majority of plasma microvesicles, change under a plethora of diseases affecting not only the hematological, but also the nervous, cardiovascular, and urinary systems, among others. In fact, there is evidence that microvesicles released by blood cells are significant contributors towards pathophysiological states, having inflammatory and/or coagulation and/or immunomodulatory arms, by either promoting or inhibiting the relative disease phenotypes. Consequently, even though microvesicles are typically considered to have adverse links with disease prognosis, progression, or outcomes, not infrequently, they exert protective roles in the affected cells. Based on these functional relations, microvesicles might represent promising disease biomarkers with diagnostic, monitoring, and therapeutic applications, equally to the more thoroughly studied exosomes. In the current review, we provide a summary of the features of microvesicles released by blood cells and their potential implication in hematological and non-hematological diseases

Climate Changes Exacerbate the Spread of Ixodes ricinus and the Occurrence of Lyme Borreliosis and Tick-Borne Encephalitis in Europe&mdash;How Climate Models Are Used as a Risk Assessment Approach for Tick-Borne Diseases

Climate change has influenced the transmission of a wide range of vector-borne diseases in Europe, which is a pressing public health challenge for the coming decades. Numerous theories have been developed in order to explain how tick-borne diseases are associated with climate change. These theories include higher proliferation rates, extended transmission season, changes in ecological balances, and climate-related migration of vectors, reservoir hosts, or human populations. Changes of the epidemiological pattern have potentially catastrophic consequences, resulting in increasing prevalence of tick-borne diseases. Thus, investigation of the relationship between climate change and tick-borne diseases is critical. In this regard, climate models that predict the ticks&rsquo; geographical distribution changes can be used as a predicting tool. The aim of this review is to provide the current evidence regarding the contribution of the climatic changes to Lyme borreliosis (LB) disease and tick-borne encephalitis (TBE) and to present how computational models will advance our understanding of the relationship between climate change and tick-borne diseases in Europe

Low T3 Syndrome in severely ill patients with COVID-19 infection

Introduction The coronavirus disease (COVID-19) is an infectious disease, caused by the SARS-CoV-2 virus, which causes severe respiratory disease. Critical ill patients often experience a condition known as Low T3 Syndrome (LT3S). Previous studies showed an association between low FT3 levels and mortality among patients with COVID-19. Moreover, thyroid hormones might be altered by cigarette consumption. Τhe aim of this study was to investigate the association of LT3S with mortality and the severity and risk of intubation in critically ill patients with COVID-19 infection, and to explore whether this association is confounded by smoking. Methods A total of 105 critically ill patients aged ≥18 years, with laboratoryconfirmed (RT-PCR) COVID-19 were enrolled. The study was conducted between January 2021 and October 2021 in the Intensive Care Unit of the 1st Department Respiratory Medicine in ‘Sotiria’ Hospital and laboratory data and clinical information were retrieved retrospectively from the electronic patients record. LT3S was defined as serum levels of FT3 <2.3 pg/mL with low or normal TSH levels. Patients were divided into two groups according to serum FT3 values: group with LT3S and group without LT3S. Mortality in the ICU was the primary outcome of the study, while the risk of intubation was a secondary outcome. Results In all, 43 out of the 105 included patients were diagnosed with LT3S. Patients in the LT3S group were older than those with non LT3S [median (IQR): 62 (13.7) vs 52.8 (15.5), p=0.011]. Non-statistically significantly higher mortality rate, SOFA and APACHE II scores were observed in the LT3S group compared to no LT3S group (p=0.080, p=0.311 and p=0.079, respectively). Moreover, LT3S was not associated with high risk of intubation (HR=1.32; 95% CI: 0.78–2.22). Twenty-five patients (58.1%) in the LT3S group were never smokers, versus 41 (66.1%) patients in the non LT3S group. Never smokers with LT3S had significantly higher mortality rate than never smokers without LT3S (40% vs 17.1%, p=0.039), and LT3S in the never smoking subgroup was associated with an increased risk of intubation (HR=2.21; 95% CI: 1.18–4.16). Conclusions LT3S was found to be associated with mortality of patients with critical COVID-19 among never smokers but not among ex-smokers or active smokers. This finding may denote that smoking may act as a confounder of the association between LT3S and mortality. Further investigation is needed to demonstrate the impact of LT3S in critically ill patients with COVID-19 infection, as well as the role of smoking in the development of the syndrome

Deciphering the Relationship Between Free and Vesicular Hemoglobin in Stored Red Blood Cell Units

Red blood cells (RBCs) release hemoglobin (Hb)-containing extracellular vesicles (EVs) throughout their lifespan in the circulation, and especially during senescence, by spleen-facilitated vesiculation of their membrane. During ex vivo aging under blood bank conditions, the RBCs lose Hb, both in soluble form and inside EVs that accumulate as a part of storage lesion in the supernatant of the unit. Spontaneous hemolysis and vesiculation are increasingly promoted by the storage duration, but little is known about any physiological linkage between them. In the present study, we measured the levels of total extracellular and EV-enclosed Hb (EV-Hb) in units of whole blood (n = 36) or packed RBCs stored in either CPDA-1 (n = 99) or in CPD-SAGM additive solution (n = 46), in early, middle, and late storage. The spectrophotometry data were subjected to statistical analysis to detect possible correlation(s) between storage hemolysis and EV-Hb, as well as the threshold (if any) that determines the area of this dynamic association. It seems that the percentage of EV-Hb is negatively associated with hemolysis levels from middle storage onward by showing low to moderate correlation profiles in all strategies under investigation. Moreover, 0.17% storage hemolysis was determined as the potential cut-off, above which this inverse correlation is evident in non-leukoreduced CPDA units. Notably, RBC units with hemolysis levels &gt; 0.17% are characterized by higher percentage of nanovesicles (&lt;100 nm) over typical microvesicles (100-400 nm) compared with the lower hemolysis counterparts. Our results suggest an ordered loss of Hb during RBC accelerated aging that might fuel targeted research to elucidate its mechanistic basis

The Emerging Role of Extracellular Vesicles and Autophagy Machinery in NASH&mdash;Future Horizons in NASH Management

Non-alcoholic fatty liver disease (NAFLD) is considered the most frequent chronic hepatic disease in the general population, while it is the first cause of liver transplantation in the US. NAFLD patients will subsequently develop non-alcoholic steatohepatitis (NASH), which is characterized by aberrant hepatocellular inflammation with or without the presence of fibrosis. The lack of specific biomarkers and therapeutic strategies makes non-alcoholic steatohepatitis (NASH) management a difficult task for clinicians. Extracellular vesicles (EVs) constitute a heterogenic population of vesicles produced by inward or outward plasma-membrane budding. There is an emerging connection between autophagy EVs production, via an unconventional non-degradative procedure. Alterations in the amount of the secreted EVs and the cargo they carry are also involved in the disease progression and development of NASH. Autophagy constitutes a multistep lysosomal degradative pathway that reassures cell homeostasis and survival under stressful conditions, such as oxygen and energy deprivation. It prevents cellular damage by eliminating defected proteins or n&omicron;n-functional intracellular organelles. At the same time, it reassures the optimal conditions for the cells via a different mechanism that includes the removal of cargo via the secretion of EVs. Similarly, autophagy machinery is also associated with the pathogenetic mechanism of NAFLD, while it has a significant implication for the progression of the disease and the development of NASH. In this review, we will shed light on the interplay between autophagy and EVs in NASH, the emerging connection of EVs production with the autophagy pathway, and their possible manipulation for developing future therapeutic strategies for NASH

Prevalence and clinical implications of respiratory viruses in asthma during stable disease state and acute attacks:Protocol for a meta-analysis

Introduction Viruses are detected in over 50% of acute asthma attacks and in a notable proportion of patients with asthma during stable disease state They are associated with worse outcomes. We will conduct a series of systematic reviews and meta-analyses to quantify the prevalence and clinical burden of various respiratory viruses in stable asthma and acute asthma attacks. In addition, we will assess the viral loads of respiratory viruses during stable and acute asthma, to explore whether viral load could differentiate attacks triggered by viruses versus those where viruses are present as “innocent bystanders”. Materials and methods Based on a prospectively registered protocol (PROSPERO, ID: CRD42023375108) and following standard methodology recommended by Cochrane, we will systematically search Medline/PubMed, EMBASE, the Cochrane Library and relevant conference proceedings for studies assessing the prevalence or clinical burden of respiratory viruses in asthma. Methodological rigour of the included studies will be appraised using a tool specific for prevalence studies and the Newcastle-Ottawa Scale respectively. In anticipation of significant clinical and methodological heterogeneity, we will conduct random effect meta-analyses. For evaluating the prevalence of viruses, we will perform meta-analyses of proportions using the inverse variance method, and the Freeman-Tukey transformation. We will conduct meta-regression analyses for exploring heterogeneity. Conclusion We envisage that these systematic reviews and meta-analyses will quantify the prevalence and burden of respiratory viruses in stable and acute asthma and will drive future research and clinical practice.</p

Red Blood Cell Abnormalities as the Mirror of SARS-CoV-2 Disease Severity: A Pilot Study

PurposeUnraveling the pathophysiology of COVID-19 disease is of crucial importance for designing treatment. The purpose of this study is to investigate the effects of the disease on erythrocytes (RBCs) and to correlate the findings with disease severity. Materials and MethodsHospitalized patients (n = 36) with COVID-19 and control group of healthy volunteers (n = 18) were included in the study. Demographic data, clinical, laboratory and chest Computed Tomography (CT) findings at time of admission were recorded. Laboratory measurements included: Hemoglobin (H b), indirect billirubin, LDH, D-Dimers, and plasma free hemoglobin (plasma free-Hb). On RBCs were performed: osmotic fragility (MCF), Free-Hb after mechanical stress (Free-Hb-MECH), intracellular RBC concentration of calcium ions (iCa(2+)), intracellular ROS (iROS), G6PD, intracellular active caspase-3 (RBC-caspase-3), IgG immunoglobulins (RBC-IgGs), which are bound on RBCs’ senescent neo-antigen proteins and RBC surface phosphatidylserine (RBC-PS). ResultsThe percentage of males was 50 and 66% and the mean age was 65.16 +/- 14.24 and 66.33 +/- 13.48 years among patients and controls respectively (mean +/- SD, p = 0.78). Upon admission patients’ PO2/FiO(2) ratio was 305.92 +/- 76.75 and distribution of infiltration extend on chest CT was: 0-25% (N = 19), 25-50%: (N = 7), and 50-75% (N = 9). Elevated hemolysis markers (LDH and plasma free-Hb) were observed in patients compared to the control group. Patients’ RBCs were more sensitive to mechanical stress, and exhibited significantly elevated apoptotic markers (iCa(2+), RBC-PS). Plasma free Hb levels correlated with the extend of pulmonary infiltrates on chest CT in COVID-19 patients. Surprisingly, patients’ RBC-iROS were decreased, a finding possibly related with the increased G6PDH levels in this group, suggesting a possible compensatory mechanism against the virus. This compensatory mechanism seemed to be attenuated as pulmonary infiltrates on chest CT deteriorated. Furthermore, RBC-IgGs correlated with the severity of pulmonary CT imaging features as well as the abnormality of lung function, which are both associated with increased disease severity. Lastly, patients’ D-Dimers correlated with RBC surface phosphatidylserine, implying a possible contribution of the red blood cells in the thrombotic diathesis associated with the SARS-CoV-2 disease. ConclusionThis pilot study suggests that SARS-CoV-2 infection has an effect on red blood cells and there seems to be an association between RBC markers and disease severity in these patients

Prevalence and clinical implications of respiratory viruses in asthma during stable disease state and acute attacks: protocol for a meta-analysis

Introduction: viruses are detected in over 50% of acute asthma attacks and in a notable proportion of patients with asthma during stable disease state They are associated with worse outcomes. We will conduct a series of systematic reviews and meta-analyses to quantify the prevalence and clinical burden of various respiratory viruses in stable asthma and acute asthma attacks. In addition, we will assess the viral loads of respiratory viruses during stable and acute asthma, to explore whether viral load could differentiate attacks triggered by viruses versus those where viruses are present as "innocent bystanders".Materials and methods: based on a prospectively registered protocol (PROSPERO, ID: CRD42023375108) and following standard methodology recommended by Cochrane, we will systematically search Medline/PubMed, EMBASE, the Cochrane Library and relevant conference proceedings for studies assessing the prevalence or clinical burden of respiratory viruses in asthma. Methodological rigour of the included studies will be appraised using a tool specific for prevalence studies and the Newcastle-Ottawa Scale respectively. In anticipation of significant clinical and methodological heterogeneity, we will conduct random effect meta-analyses. For evaluating the prevalence of viruses, we will perform meta-analyses of proportions using the inverse variance method, and the Freeman-Tukey transformation. We will conduct meta-regression analyses for exploring heterogeneity.Conclusion: we envisage that these systematic reviews and meta-analyses will quantify the prevalence and burden of respiratory viruses in stable and acute asthma and will drive future research and clinical practice.</p