Natural genetic diversity of the DBL domain of a novel member of the Plasmodium vivax erythrocyte binding-like proteins (EBP2) in the Amazon rainforest.

In malaria parasites, the erythrocyte binding-like proteins (EBL) are a family of invasion proteins that are attractive vaccine targets. In the case of Plasmodium vivax, the widespread malaria parasite, blood-stage vaccines have been largely focused on a single EBL candidate, the Duffy binding-like domain (DBL) of the Duffy binding protein (DBPII), due to its well-characterized role in the reticulocyte invasion. A novel P. vivax EBL family member, the Erythrocyte binding protein (EBP2, also named EBP or DBP2), binds preferentially to reticulocytes and may mediate an alternative P. vivax invasion pathway. To gain insight into the natural genetic diversity of the DBL domain of EBP2 (region II; EBP2-II), we analyzed ebp2-II gene sequences of 71 P. vivax isolates collected in different endemic settings of the Brazilian Amazon rainforest, where P. vivax is the predominant malaria-associated species. Although most of the substitutions in the ebp2-II gene were non-synonymous and suggested positive selection, the results showed that the DBL domain of the EBP2 was much less polymorphic than that of DBPII. The predominant EBP2 haplotype in the Amazon region corresponded to the C127 reference sequence first described in Cambodia (25% C127-like haplotype). An overview of ebp2-II gene sequences available at GenBank (n = 352) from seven countries (Cambodia, Madagascar, Myanmar, PNG, South Korea, Thailand, Vietnam) confirmed the C127-like haplotype as highly prevalent worldwide. Two out of 43 haplotypes (5 to 20 inferred per country) showed a global frequency of 60%. The results presented here open new avenues of research pursuit while suggesting that a vaccine based on the DBL domain of EBP2 should target a few haplotypes for broad coverage.

Probing the Antiplasmodial Properties of Plakortinic Acids C and D: An Uncommon Pair of Marine Peroxide-Polyketides Isolated from a Two-Sponge Association of Plakortis symbiotica and Xetospongia deweerdtae Collected near Puerto Rico.

Plakortinic acids C (1) and D (2), an unseparable pair of endoperoxide polyketides isolated and purified from the symbiotic association of Caribbean Sea sponges Plakortis symbiotica-Xestospongia deweerdtae, underwent in vitro evaluation for antiplasmodial activity against the malaria parasite Plasmodium berghei using a drug luminescence assay. Initial screening at 10 µM revealed 50% in vitro parasite growth inhibition. The title compounds displayed antiplasmodial activity with an EC50 of 5.3 µM toward P. berghei parasites. The lytic activity against erythrocytes was assessed through an erythrocyte cell lysis assay, which showed non-lytic activity at lower concentrations ranging from 1.95 to 3.91 µM. The antiplasmodial activity and the absence of hemolytic activity support the potential of plakortinic acids C (1) and D (2) as promising lead compounds. Moreover, drug-likeness (ADMET) properties assessed through the pkCSM server predicted high intestinal absorption, hepatic metabolism, and volume of distribution, indicating favorable pharmacokinetic profiles for oral administration. These findings suggest the potential suitability of these metabolites for further investigations of antiplasmodial activity in multiple parasitic stages in the mosquito and Plasmodium falciparum. Notably, this study represents the first report of a marine natural product exhibiting the unique 7,8-dioxatricyclo[4.2.2.02,5]dec-9-ene motif being evaluated against malaria.

Red blood cell transfusions in preterm infants in 2021: a narrative review / Transfusão de células vermelhas em prematuros em 2021: uma revisão narrativa

Anemia is frequent in preterm infants. Red blood cell transfusion practices vary between different centers. The objective of this study was to review red blood cell transfusion practices in preterm infants between 2020 and 2021. This was a narrative review that included studies published on PubMed (Medline) and Web of Science between October 2020 and October 2021. Ten studies were included finally. Red blood cell transfusion frequency was variable. Some neonatal units did not report transfusion protocols. Most studies reported volumes of 10-15 ml/kg per transfusion. The implementation of an anemia care bundle and adoption of restrictive transfusion resulted in a reduction in the number of transfusions, the volume transfused, and a reduction in the rate of multiple transfusions. We suggest that neonatal units that care for preterm infants should have a transfusion protocol based on the best evidence available and this issue may improve.

A anemia é frequente nos bebês prematuros. As práticas de transfusão de glóbulos vermelhos variam entre os diferentes hospitais. O objetivo deste estudo foi revisar as práticas de transfusão de glóbulos vermelhos em bebês prematuros entre 2020 e 2021. Esta foi uma revisão narrativa que incluiu estudos publicados no PubMed (Medline) e Web of Science entre outubro de 2020 e outubro de 2021. Dez estudos foram definitivamente incluídos. A frequência de transfusão de glóbulos vermelhos foi variável. Algumas unidades neonatais não relataram protocolos de transfusão. A maioria dos estudos relatou volumes de 10-15 ml/kg por transfusão. A implantação de um conjunto de cuidados para anemia e a adoção de transfusão restritiva resultaram em uma redução do número de transfusões, do volume transfundido e uma redução na taxa de transfusões múltiplas. Sugerimos que as unidades neonatais que prestam cuidados a bebês prematuros devem ter um protocolo de transfusão baseado em evidências para que todo esse problema melhore.

Mechanical Characterization of the Erythrocyte Membrane Using a Capacitor-Based Technique.

Pathological processes often change the mechanical properties of cells. Increased rigidity could be a marker of cellular malfunction. Erythrocytes are a type of cell that deforms to squeeze through tiny capillaries; changes in their rigidity can dramatically affect their functionality. Furthermore, differences in the homeostatic elasticity of the cell can be used as a tool for diagnosis and even for choosing the adequate treatment for some illnesses. More accurate types of equipment needed to study biomechanical phenomena at the single-cell level are very costly and thus out of reach for many laboratories around the world. This study presents a simple and low-cost technique to study the rigidity of red blood cells (RBCs) through the application of electric fields in a hand-made microfluidic chamber that uses a capacitor principle. As RBCs are deformed with the application of voltage, cells are observed under a light microscope. From mechanical force vs. deformation data, the elastic constant of the cells is determined. The results obtained with the capacitor-based method were compared with those obtained using optical tweezers, finding good agreement. In addition, P. falciparum-infected erythrocytes were tested with the electric field applicator. Our technique provides a simple means of testing the mechanical properties of individual cells.

Evaluation of Cytotoxic effect of Moringa peregrina seeds on Oral Cancer, CAL 27, Cell Line and Red Blood Cells Hemolysis / Evaluación del efecto citotóxico de las semillas de Moringa peregrina en el cáncer oral, CAL 27, líneas celulares y hemólisis de glóbulos rojos

Background: Moringa peregrina Forssk is a well-known plant in ethnomedicine due to its widespread uses in various diseases like cough, wound healing, rhinitis, fever, and detoxification. The plant seeds contain compounds that are cytotoxic to many cancer cells. During the therapeutic use of plants via the oral route, some compounds present in the plants may be cytotoxic to normal cell lines and red blood cells. Objective: This study was the first report of investigation of the cytotoxic profile on oral cancer, CAL 27, cell line, and hemolytic activities on human erythrocytes of Moringa peregrina seeds ethanolic extract (MPSE). Methods: MPSE was screened for its cytotoxic effect against oral cancer, CAL 27, cell line using 3-(4, 5-dimethylthiazol-2-yl)-2, 5,-diphenyltetrazolium bromide (MTT) assay. The toxicity of MPSE on human erythrocytes was determined by in vitro hemolytic assay. Results: MPSE showed significant anti-proliferative activity against oral cancer, CAL 27 cell line at lower concentrations with half maximal inhibitory concentration (IC50) value of 21.03 µg/mL. At 1,000 µg/ml of MPSE, the maximum hemolysis was found to be 14.3% which is within safer limit. Conclusions: This study revealed a potential anti-oral cancer of MPSE and provided a baseline for its potential use in oral cancer treatment with minimum hemolytic effect on human RBCs.

La Moringa peregrina Forssk es una planta muy conocida en etnomedicina debido a sus usos generalizados en diversas enfermedades como la tos, la cicatrización de heridas, la rinitis, la fiebre y la desintoxicación. Las semillas de la planta contienen compuestos citotóxicos para muchas células cancerosas. Durante el uso terapéutico de las plantas por vía oral, algunos compuestos presentes en ellas pueden ser citotóxicos para las líneas celulares normales y los glóbulos rojos. Objetivo: Este estudio fue el primer informe de investigación del perfil citotóxico sobre el cáncer oral, CAL 27, línea celular, y las actividades hemolíticas en eritrocitos humanos del extracto etanólico de semillas de Moringa peregrina (MPSE). Métodos: Se examinó el efecto citotóxico del MPSE contra la línea celular de cáncer oral CAL 27 mediante el ensayo con bromuro de 3-(4, 5-dimetiltiazol-2-il)-2, 5,-difeniltetrazolio (MTT). La toxicidad del MPSE sobre los eritrocitos humanos se determinó mediante un ensayo hemolítico in vitro. Resultados: MPSE mostró una actividad antiproliferativa significativa contra el cáncer oral, línea celular CAL 27 a concentraciones más bajas con un valor de concentración inhibitoria media máxima (IC50) de 21,03 µg/mL. A 1.000 µg/ml de MPSE, la hemólisis máxima fue del 14,3%, lo que está dentro del límite de seguridad. Conclusiones: Este estudio reveló un potencial anticancerígeno oral de MPSE y proporcionó una base para su uso potencial en el tratamiento del cáncer oral con un efecto hemolítico mínimo en los glóbulos rojos humanos.

Unraveling DEHP influence on hemoglobin S polymerization in sickle cell disease: Ex vivo, in vitro and in silico analysis.

Sickle cell disease (SCD) is a hereditary hemoglobinopathy, caused by a mutation at position 6 of the ß-globin chain and patients are frequently exposed to several blood transfusions in order to maintain physiological function. Transfusion blood bags are composed of PVC and phthalates (as DEHP) are often introduced to the material in order to confer malleability. In this sense, DEHP can easily elute to the blood and cause harmful effects. This study aimed to unravel DEHP effect on SCD patient's hemoglobin function. We found that HbS polymerization using whole erythrocytes is decreased by DEHP in ex vivo experiments and this effect might be mediated by the DEHP-VAL6 interaction, evaluated in silico. Isolated HbS exhibited less polymerization at low DEHP concentrations and increased polymerization rate at higher concentration. When analyzing the propensity to aggregate, HbS is more inclined to aggregate when compared to HbA due to the residue 6 mutation. Circular dichroism showed characteristic hemoglobin peaks for oxygenated HbS that are lost when oxygen is sequestered, and DEHP at higher concentration mildly recovers a peak close to the second hemoglobin one. Finally, by transmission electron microscopy we demonstrated that high DEHP concentration increased polymer formation with a more organized structure. These findings show for the first-time the beneficial effect of low-dose DEHP on HbS polymerization.

P. falciparum Invasion and Erythrocyte Aging.

Plasmodium parasites need to find red blood cells (RBCs) that, on the one hand, expose receptors for the pathogen ligands and, on the other hand, maintain the right geometry to facilitate merozoite attachment and entry into the red blood cell. Both characteristics change with the maturation of erythrocytes. Some Plasmodia prefer younger vs. older erythrocytes. How does the life evolution of the RBC affect the invasion of the parasite? What happens when the RBC ages? In this review, we present what is known up until now.

Erythrocyte Vulnerability to Airborne Nanopollutants.

The toxicological impact of airborne polluting ultrafine particles (UFPs, also classified as nanoparticles with average sizes of less than 100 nm) is an emerging area of research pursuing a better understanding of the health hazards they pose to humans and other organisms. Hemolytic activity is a toxicity parameter that can be assessed quickly and easily to establish part of a nanoparticle's behavior once it reaches our circulatory system. However, it is exceedingly difficult to determine to what extent each of the nanoparticles present in the air is responsible for the detrimental effects exhibited. At the same time, current hemolytic assessment methodologies pose a series of limitations for the interpretation of results. An alternative is to synthesize nanoparticles that model selected typical types of UFPs in air pollution and evaluate their individual contributions to adverse health effects under a clinical assay of osmotic fragility. Here, we discuss evidence pointing out that the absence of hemolysis is not always a synonym for safety; exposure to model nanopollutants, even at low concentrations, is enough to increase erythrocyte susceptibility and dysfunction. A modified osmotic fragility assay in combination with a morphological inspection of the nanopollutant-erythrocyte interaction allows a richer interpretation of the exposure outcomes. Membrane-nanoparticle interplay has a leading role in the vulnerability observed. Therefore, future research in this line of work should pay special attention to the evaluation of the mechanisms that cause membrane damage.

Next Generation Sequencing of Red Blood Cell Antigens in Transfusion Medicine: Systematic Review and Meta-Analysis.

Molecular analysis of blood groups is important in transfusion medicine, allowing the prediction of red blood cell (RBC) antigens. Many blood banks use single nucleotide variant (SNV) based methods for blood group analysis. While this is a well-established approach, it is limited to the polymorphisms included in genotyping panels. Thus, variants that alter antigenic expression may be ignored, resulting in incorrect prediction of phenotypes. The popularization of next-generation sequencing (NGS) has led to its application in transfusion medicine, including for RBC antigens determination. The present review/meta-analysis aimed to evaluate the applicability of the NGS for the prediction of RBC antigens. A systematic review was conducted following a comprehensive literature search in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. Studies were selected based on predefined criteria and evaluated using Strengthening the Reporting of Observational studies in Epidemiology guidelines. The characteristics and results of the studies were extracted and meta-analysis was performed to verify the agreement between results from standard molecular methods and NGS. Kell (rs8176058), Duffy (rs2814778, rs12078), or Kidd (rs1085396) alleles were selected as a model for comparisons. Additionally, results are presented for other blood group systems. Of the 864 eligible studies identified, 10 met the inclusion criteria and were selected for meta-analysis. The pooled concordance proportion for NGS compared to other methods ranged from 0.982 to 0.994. The sequencing depth coverage was identified as crucial parameters for the reliability of the results. Some studies reported difficulty in analyzing more complex systems, such as Rh and MNS, requiring the adoption of specific strategies. NGS is a technology capable of predicting blood group phenotypes and has many strengths such as the possibility of simultaneously analyzing hundred individuals and gene regions, and the ability to provide comprehensive genetic analysis, which is useful in the description of new alleles and a better understanding of the genetic basis of blood groups. The implementation of NGS in the routine of blood banks depends on several factors such as cost reduction, the availability of widely validated panels, the establishment of clear quality parameters and access to bioinformatics analysis tools that are easy to access and operate.

Novel bioanalytical strategy using isotope pattern deconvolution and ICP-QMS for the study of iron incorporation in erythrocytes: An insight to better assessment.

Iron is an essential element for human life and its nutritional status in the human body is directly linked to human health. More than 1015 atoms of iron per second are necessary for the maintenance of haemoglobin formation. To predict iron bioavailability three approaches are normally employed: (a) faecal recovery; (b) plasma appearance; and (c) erythrocyte incorporation (the most used). Isotope Pattern Deconvolution (IPD) is a mathematical tool that allows the isolation of distinct isotope signatures from mixtures of natural abundance and enriched tracers. In this work we propose a novel strategy to assess erythrocyte iron incorporation, based on the use of an iron stable isotope (57Fe) and the IPD concept. This strategy allows direct calculation of the exogenous concentration of 57Fe incorporated into RBCs after supplementation. In this way, to determine the mass of iron incorporated into erythrocytes, the unique prediction that must be made is the blood volume, estimate to reproduce the natural dilution of the tracer (57Fe) in the blood. This novel bioanalytical approach was applied for the measurements of iron incorporation and further iron absorption studies in humans, using a group of twelve healthy participants, that should be further evaluated for the assessment of other chemical elements that could be of health concerns and directly impact society.

Transfusion of packed red blood cells in adults with sickle cell anemia treated at an emergency hospital

SUMMARY OBJECTIVE: The aim of this study was to analyze the prescription of packed red blood cells performed by emergency physicians for adults with sickle cell anemia. METHODS: Transfusions performed in adults with sickle cell anemia treated at an emergency service in São Bernardo do Campo, São Paulo Brazil, between January 2018 and January 2022 were evaluated. For data comparison, the chi-square2 test was used. The significance level adopted was 5%. RESULTS: A total of 114 transfusions were performed. The mean age was 41.8±16.4 years, and pretransfusion hemoglobin was 6.1±1.23 g/dL. Regarding the indication, the adequacy of transfusions performed in symptomatic individuals was significantly higher compared to asymptomatic individuals (100% vs. 3.9%, p<0.001). Symptomatic individuals received excessive volumes of packed red blood cells less frequently than asymptomatic individuals (17.5% vs. 56.9%, p<0.001). The filtered subtype, indicated for sickle cell anemia, was prescribed in only a quarter of the patients. However, non-indicated subtypes were frequently prescribed. CONCLUSION: This study found low adequacy in the indication and calculation of the transfusion volume of packed red blood cells in asymptomatic individuals. Few patients received filtered red blood cells, resulting in increased risks of transfusion reactions. On the contrary, non-indicated subtypes were prescribed in a quarter of transfusions, which resulted in higher costs and delay in receiving packed red blood cells.

Oxidative Stress in Healthy and Pathological Red Blood Cells.

Red cell diseases encompass a group of inherited or acquired erythrocyte disorders that affect the structure, function, or production of red blood cells (RBCs). These disorders can lead to various clinical manifestations, including anemia, hemolysis, inflammation, and impaired oxygen-carrying capacity. Oxidative stress, characterized by an imbalance between the production of reactive oxygen species (ROS) and the antioxidant defense mechanisms, plays a significant role in the pathophysiology of red cell diseases. In this review, we discuss the most relevant oxidant species involved in RBC damage, the enzymatic and low molecular weight antioxidant systems that protect RBCs against oxidative injury, and finally, the role of oxidative stress in different red cell diseases, including sickle cell disease, glucose 6-phosphate dehydrogenase deficiency, and pyruvate kinase deficiency, highlighting the underlying mechanisms leading to pathological RBC phenotypes.

El ancho de distribución eritrocitaria en el pronóstico de corrección quirúrgica de cardiopatías congénitas / Red cell distribution width in the prognosis of surgical correction of congenital heart diseases

Resumen Objetivo: Evaluar la capacidad del ancho de distribución eritrocitaria (ADE) para predecir la mortalidad en niños sometidos a cirugía cardiovascular en la Fundación Hospital Infantil Napoleón Franco Pareja, en Colombia. Método: Estudio analítico de corte transversal retrospectivo que incluyó 45 individuos de 0 a 17 años operados de cardiopatía congénita. Se aplicaron la escala RACHS-1 (Risk Adjustment in Congenital Heart Surgery) y variables de laboratorio, incluyendo el ADE. La asociación entre el ADE y la mortalidad se determinó mediante análisis por curva ROC y correlación rho de Spearman. Resultados: Un ADE superior al 15.52% representó 1.6 veces más riesgo, comparado con los individuos por debajo de ese valor (intervalo de confianza del 95%: 1.01-2.6; p = 0.034). Los valores del ADE no se correlacionaron con los días de estancia hospitalaria ni con las complicaciones. El ADE prequirúrgico y el puntaje RACHS-1 fueron significativamente mayores en el grupo de mortalidad. La relación entre el ADE prequirúrgico y el puntaje RACHS-1 fue significativa. Conclusiones: En nuestro estudio, el ADE prequirúrgico presentó un poder moderado para discriminar la mortalidad perioperatoria en la corrección quirúrgica de cardiopatías congénitas. Se precisan más estudios con mayor tamaño de muestra.

Abstract Objective: To evaluate the capacity of red cell distribution width (RDW) to predict mortality in children undergoing cardiovascular surgery at the Fundación Hospital Infantil Napoleón Franco Pareja, in Colombia. Method: Retrospective cross-sectional analytical study that included 45 individuals aged 0 to 17 years operated for congenital heart disease. The RACHS-1 (Risk Adjustment in Congenital Heart Surgery) scale and laboratory variables including the RDW were applied. The association between RDW and mortality was determined by ROC curve analysis and Spearman's rho correlation. Results: An RDW greater than 15.52% represented 1.6 times more risk, compared to individuals below that value (95% confidence interval: 1.01-2.6; p = 0.034). The RDW values did not correlate with days of hospital stay or complications. The preoperative RDW and RACHS-1 score were significantly higher in the mortality group. The relationship between presurgical RDW and the RACHS-1 score was significant. Conclusions: In our study, the preoperative RDW had moderate power to discriminate perioperative mortality in the surgical correction of congenital heart disease. More studies with a larger sample size are required.

Nanoarchitectonic approaches for measuring the catalytic behavior of a membrane anchored enzyme. From Langmuir-Blodgett to a novel Langmuir-Schaefer based nanofilm building device.

Self-organized lipid monolayers at the air-water interface (Langmuir films, LF) are commonly used for measuring the catalytic properties of membrane-bound enzymes. This methodology allows to provide a consistent flat topography molecular density, packing defects and thickness. The aim of the present work was to show the methodological advantages of using the horizontal transfer method (Langmuir-Schaefer) with respect to the vertical transfer method (Langmuir-Blodgett) when mounting a device to measure catalytic activity of membrane enzymes. Based on the results obtained we can conclude that it is possible to prepare stable Langmuir-Blodgett (LB) and Langmuir-Schaefer (LS) films from Bovine Erythrocyte Membranes (BEM) preserving the catalytic activity of its native Acetylcholinesterase (BEA). In comparison, the LS films showed Vmax values more similar to the enzyme present in the vesicles of natural membranes. In addition, it was much easier to produce large amounts of transferred areas with the horizontal transfer methodology. It was possible to decrease the time required to mount an assay with numerous activity points, such as building activity curves as a function of substrate concentration. The present results show that LSBEM provides a proof of concept for the development of biosensors based on transferred purified membrane for the screening of new products acting on an enzyme embedded on its natural milieu. In the case of BEA, the application of these enzymatic sensors could have medical interest, providing drug screening tools for the treatment of Alzheimer's disease.

Evaluation of the Hematological Patterns from Up to 985 Days of Long COVID: A Cross-Sectional Study.

Long COVID affects many individuals following acute coronavirus disease 2019 (COVID-19), and hematological changes can persist after the acute COVID-19 phase. This study aimed to evaluate these hematological laboratory markers, linking them to clinical findings and long-term outcomes in patients with long COVID. This cross-sectional study selected participants from a 'long COVID' clinical care program in the Amazon region. Clinical data and baseline demographics were obtained, and blood samples were collected to quantify erythrogram-, leukogram-, and plateletgram-related markers. Long COVID was reported for up to 985 days. Patients hospitalized in the acute phase had higher mean red/white blood cell, platelet, and plateletcrit levels and red blood cell distribution width. Furthermore, hematimetric parameters were higher in shorter periods of long COVID than in longer periods. Patients with more than six concomitant long COVID symptoms had a higher white blood cell count, a shorter prothrombin time (PT), and increased PT activity. Our results indicate there may be a compensatory mechanism for erythrogram-related markers within 985 days of long COVID. Increased levels of leukogram-related markers and coagulation activity were observed in the worst long COVID groups, indicating an exacerbated response after the acute disturbance, which is uncertain and requires further investigation.

Micronuclei in embryos of eight seabird species in northwestern Mexico: A biomarker of exposure to coastal pollution?

The micronucleus (MN) test may be used to evaluate genome instability in birds and the potential of different species to function as biomarkers of genotoxicity. However, little is known regarding genome instability in seabird embryos or the instability present among embryonic development stages. Therefore, the present study aimed to describe the frequencies of micronucleated erythrocytes (MNE) and micronucleated polychromatic erythrocytes (MNPCE) in blood samples collected from the embryos of eight seabird species nesting on the coast of Sinaloa, Mexico. An additional description of blood cell maturation along with embryo development during incubation was conducted based on the proportion of polychromatic erythrocytes (PCE), and the potential relationships between metals (Hg and Cd concentrations in egg content) and the MN frequencies in embryo blood were evaluated. The PCE proportion appears to decline as incubation advances (initial stage > intermediate stage > advanced stage), and the values varied between species (Suliformes/Pelecaniformes < Charadriiformes: Laridae), which may be related to differences among incubation periods and reproductive strategies. Interspecific variation in the MNPCE frequency was found in embryos showing advanced development, which could be related to both variations in life-history traits and ecological factors and not Hg or Cd exposure. The genomic instability values in this study are the first to be reported for embryos of seabird species nesting in a subtropical coastal region.

Bosentan attenuates sickle cell disease erythrocyte HbS polymerization and impaired deformability induced by endothelin-1.

The effects of endothelin-1 (ET-1) on erythrocytes from sickle cell disease (SCD) patients have been described, but mechanisms of ET-1 regarding primary erythrocyte functions remain unknown. ET-1 is a vasoconstrictor peptide produced by endothelial cells, and the expression of ET-1 is increased in SCD. The present study used ex vivo experiments with sickle cell erythrocytes, ET-1, and bosentan, a dual antagonist of ETA and ETB receptors. We performed a hemoglobin S (HbS) polymerization assay with three concentrations of ET-1 (1, 20, and 50 pg/mL) and bosentan (100 nmol/L). ET-1 increased HbS polymerization at all concentrations, and this effect was suppressed by bosentan. For the deformability assay, red blood cells (RBCs) were incubated on a Sephacryl column with the same concentrations of ET-1 and bosentan. ET-1 decreased deformability, and this effect was reversed by bosentan. To observe erythrocyte adhesion, ET-1 and bosentan were incubated with RBCs in thrombospondin-coated 96-well plate, which demonstrated that ET-1 decreased adhesion but that bosentan enhanced adhesion. We also assessed erythrocyte apoptosis and observed decreased eryptosis induced by ET-1, and these effects were inhibited bosentan. Thus, these findings demonstrated that ET-1 modulates HbS polymerization, erythrocyte deformability, adhesion to thrombospondin, and eryptosis, and these effects were suppressed or enhanced by bosentan.

The Inflammatory Biomarkers Behavior Profile of Patients Following Elective Degenerative Spine Surgery and Differences Compared to Those Coursing With a Postoperative Spinal Infection: Protocol for a Systematic Review.

BACKGROUND: The incidence of postoperative spinal infection (PSI) ranges from 0% to 10%, with devastating effects on the patient prognosis because of higher morbidity while increasing costs to the health care system. PSIs are elusive and difficult to diagnose, especially in the early postoperative state, because of confusing clinical symptoms, rise in serum biomarkers, or imaging studies. Current research on diagnosis has focused on serum biomarkers; nevertheless, most series rely on retrospective cohorts where biomarkers are studied individually and at different time points. OBJECTIVE: This paper presents the protocol for a systematic review that aims to determine the inflammatory biomarker behavior profile of patients following elective degenerative spine surgery and their differences compared to those coursing with PSIs. METHODS: The proposed systematic review will follow the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. This protocol was registered at PROSPERO on January 19, 2022. We will include studies related to biomarkers in adult patients operated on for degenerative spinal diseases and those developing PSIs. The following information will be extracted from the papers: (1) study title; (2) study author; (3) year; (4) evidence level; (5) research type; (6) diagnosis group (elective postoperative degenerative disease or PSI); (7a) region (cervical, thoracic, lumbosacral, and coccygeal); (7b) type of infection by anatomical or radiological site; (8) surgery type (including instrumentation or not); (9) number of cases; (10) mean age or individual age; (11) individual serum biomarker values from the preoperative state up to 90 days postoperative for both groups, including (10a) interleukin-6, (10b) presepsin, (10c) erythrocyte sedimentation rate, (10d) leukocyte count, (10e) neutrophil count, (10f) C-reactive protein, (10g) serum amyloid, (10h) white cell count, (10i) albumin, (10j) prealbumin, (10k) procalcitonin, (10l) retinol-associated protein, and (10m) Dickkopf-1; (11) postoperative days at symptoms or diagnosis; (12) type of organism; (13) day of starting antibiotics; (14) duration of treatment; and (15) any biases (including comorbidities, especially those affecting immunological status). All data on biomarkers will be presented graphically over time. RESULTS: No ethical approval will be required, as this review is based on published data and does not involve interaction with human participants. The search for this systematic review commenced in February 2021, and we expect to publish the findings in mid-2023. CONCLUSIONS: This study will provide the behavior profile of biomarkers for PSI and patients following elective surgery for degenerative spinal diseases from the preoperative period up to 90 days postoperative, providing cutoff values on the day of diagnosis. This research will provide clinicians with highly trustable cutoff reference values for PSI diagnosis. Finally, we expect to provide a basis for future research on biomarkers that help diagnose more accurately and in a timely manner in the early stages of illness, ultimately impacting the patient's physical and mental health, and reducing the disease burden. TRIAL REGISTRATION: PROSPERO CRD42022304645; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=304645. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/41555.

[Red cell distribution width in the prognosis of surgical correction of congenital heart diseases]. / El ancho de distribución eritrocitaria en el pronóstico de corrección quirúrgica de cardiopatías congénitas.

Objective: To evaluate the capacity of red cell distribution width (RDW) to predict mortality in children undergoing cardiovascular surgery at the Fundación Hospital Infantil Napoleón Franco Pareja, in Colombia. Method: Retrospective cross-sectional analytical study that included 45 individuals aged 0 to 17 years operated for congenital heart disease. The RACHS-1 (Risk Adjustment in Congenital Heart Surgery) scale and laboratory variables including the RDW were applied. The association between RDW and mortality was determined by ROC curve analysis and Spearman's rho correlation. Results: An RDW greater than 15.52% represented 1.6 times more risk, compared to individuals below that value (95% confidence interval: 1.01-2.6; p = 0.034). The RDW values did not correlate with days of hospital stay or complications. The preoperative RDW and RACHS-1 score were significantly higher in the mortality group. The relationship between presurgical RDW and the RACHS-1 score was significant. Conclusions: In our study, the preoperative RDW had moderate power to discriminate perioperative mortality in the surgical correction of congenital heart disease. More studies with a larger sample size are required.

Objetivo: Evaluar la capacidad del ancho de distribución eritrocitaria (ADE) para predecir la mortalidad en niños sometidos a cirugía cardiovascular en la Fundación Hospital Infantil Napoleón Franco Pareja, en Colombia. Método: Estudio analítico de corte transversal retrospectivo que incluyó 45 individuos de 0 a 17 años operados de cardiopatía congénita. Se aplicaron la escala RACHS-1 (Risk Adjustment in Congenital Heart Surgery) y variables de laboratorio, incluyendo el ADE. La asociación entre el ADE y la mortalidad se determinó mediante análisis por curva ROC y correlación rho de Spearman. Resultados: Un ADE superior al 15.52% representó 1.6 veces más riesgo, comparado con los individuos por debajo de ese valor (intervalo de confianza del 95%: 1.01-2.6; p = 0.034). Los valores del ADE no se correlacionaron con los días de estancia hospitalaria ni con las complicaciones. El ADE prequirúrgico y el puntaje RACHS-1 fueron significativamente mayores en el grupo de mortalidad. La relación entre el ADE prequirúrgico y el puntaje RACHS-1 fue significativa. Conclusiones: En nuestro estudio, el ADE prequirúrgico presentó un poder moderado para discriminar la mortalidad perioperatoria en la corrección quirúrgica de cardiopatías congénitas. Se precisan más estudios con mayor tamaño de muestra.

Morphometric analysis on erythrocytes of various livestock being reared in the Cholistan desert / Análise morfométrica de eritrócitos de vários pecuários criados no deserto de Colistão

The present study aimed to assess the influence of physiological exposure to erythrocyte indices; the morphometric parameters of the size of erythrocytes, as well as synergistic effects on the erythrocyte spectrum changes in various species being reared in different strip-wasteland conditions. We collected samples from 400 animals from the jugular veins and made 2000 blood smears, sample blood was taken by an expert veterinary doctor and transferred into an EDTA vacutainer. Blood smears were stained through the Pappenheim procedure and slides were photomicrographed under 100x objective. The parameters of morphometry of erythrocytes were largest in cattle after buffalo, sheep, while goats have the lowest one. The influence of age was significant p<0.05. The influence of sex was not significant in Cattle p<0.01, values of a parameter of erythrocytes were higher in young than in adults in sheep, goats, cattle, and buffalo. The size of erythrocytes in males was higher than females in sheep, goat, and buffalo but in cattle values of female erythrocytes were higher than in males. Further, gender, altitude, and age have a profound influence on the morphometric attributes of erythrocytes. It will be helpful in interpreting etiopathogenetic conditions in human beings and other animals.

O presente estudo teve como objetivo avaliar a influência da exposição fisiológica nos índices eritrocitários; os parâmetros morfométricos do tamanho dos eritrócitos, bem como os efeitos sinérgicos sobre as alterações do espectro eritrocitário em várias espécies criadas em diferentes condições de terreno baldio. Coletamos amostras de 400 animais das veias jugulares e fizemos 2.000 esfregaços de sangue, a amostra de sangue foi colhida por um médico veterinário especialista e transferida para um vacutainer de EDTA. Esfregaços de sangue foram corados pelo procedimento de Pappenheim e as lâminas foram fotomicrografadas sob objetiva de 100x. Os parâmetros de morfometria dos eritrócitos foram maiores em bovinos após bubalinos, ovinos, enquanto os caprinos apresentaram os menores. A influência da idade foi significativa p<0,05. A influência do sexo não foi significativa em Bovinos p<0,01, os valores de um parâmetro de eritrócitos foram maiores em jovens do que em adultos em ovinos, caprinos, bovinos e bubalinos. O tamanho dos eritrócitos nos machos foi maior que nas fêmeas em ovinos, caprinos e búfalos, mas em bovinos os valores de eritrócitos femininos foram maiores do que nos machos. Além disso, sexo, altitude e idade têm uma profunda influência nos atributos morfométricos dos eritrócitos. Será útil na interpretação de condições etiopatogenéticas em seres humanos e outros animais.