Red Blood Cell Concentration Research Articles

Effect of red blood cell concentration on the blood flow in patient-specific aneurysms

Effect of red blood cell concentration on the blood flow in patient-specific aneurysms

Quantification of hemolysis rates from pulsed field ablation

Abstract Introduction Pulsed electric fields induce hemolysis of red blood cells as a dose-dependent effect of the electric field. Voltage pulsations induce a transmembrane potential across the cell membrane and either open up or create pores in the red cells. In isotonic conditions, the pores allow passage of potassium and sodium ions but not sucrose or hemoglobin, and leakage of ions leads to an osmotic imbalance which in turn causes a colloidal hemolysis of the red cells. Objective To quantify hemolysis rates during pulsed field ablation (PFA). Methods We created a computational model of PFA to determine the total volume of blood hemolyzed from each pulse during catheter ablation using pulsed field energy. The percentage hemolysis was calculated as a function of electric field intensity utilizing existing published experimental data. A single electrode delivering a single pulse of 100 microseconds duration was modeled at voltages of 1 kV, 1.5 kV, and 2 kV. Results The total volume of hemolyzed blood per pulse increased with increasing applied voltage (Figure). For 2 electrodes in direct tissue contact, the electrode surface exposed to the blood pool generated 19 microliters of hemolyzed red blood cells with a single pulse of a 2 kV field strength. In the case of a single pulse train consisting of 50 pulses, using a catheter configuration with 20 electrodes, an estimate of total volume per pulse train is approximately 9.5 mL of hemolyzed blood. In the case of electrodes not in direct contact with endocardial tissue, and exposed to the blood pool, up to double this volume could be anticipated per pulse train. Hemolyzed volume can be reduced with better tissue contact (reducing exposure to blood), or potentially with the use of irrigation to dilute the local red blood cell concentration. Increased tonicity of the irrigant fluid may also reduce the osmotic pressure increases that result in hemolysis. Conclusions Typical voltages utilized in pulsed field ablation can cause significant hemolysis, which is exacerbated by inadequate tissue contact. A greater number of electrodes and number of pulses delivered increases the risk, whereas better tissue contact, and the use of irrigation, may reduce it.

A-066 Does essential fatty acid deficiency alter ethanolamine plasmalogen concentrations in red blood cells? Implications for clinical testing

Abstract Background Plasmalogens are glycerophospholipids characterized by a fatty alcohol at the sn-1 position, a polyunsaturated fatty acid at the sn-2 position, most commonly docosahexaenoic acid (DHA) or arachidonic acid, and a polar head group at the sn-3 position, mainly phosphoethanolamine. Markedly reduced plasmalogens are seen in peroxisome biogenesis defects, including Zellweger spectrum disorders (ZSD), since the first two steps of plasmalogen synthesis occur in peroxisomes. Disruption of the peroxisomal β-oxidation pathway also causes DHA deficiency in ZSD patients. Since plasmalogens are composed of fatty acids, the deficiency of DHA or other essential fatty acids could further decrease the plasmalogen level in ZSD patients and lower the results of plasmalogen testing in patients without ZSD. To test this hypothesis, we evaluated the impact of essential fatty acid (EFA) deficiency on plasmalogens in patients with ZSD and individuals with EFA deficiency due to unrelated causes. Methods Red blood cell (RBC) samples were obtained from individuals without ZSD referred to ARUP laboratories for clinical EFA testing (n = 80; age range: birth - 89 years), and from patients with ZSD (n = 7; age range birth - 9 years). Three ZSD patients were older and with a less severe phenotype. A total of 18 intact ethanolamine plasmalogen species were extracted from packed RBCs and quantified using a XEVO TQ-XS Mass Spectrometer in conjunction with Ultra-High Performance Liquid Chromatography (Waters). Total plasmalogen values were also calculated; plasmalogen deficiency was defined as ≤60% of age-matched control median. Fatty acids (FAs) were quantified by gas chromatography negative chemical ionization-mass spectrometry (GC-NCI-MS). EFA deficiency was diagnosed by increased Triene/Tetraene ratio (Mead acid/Arachidonic acid). Data was analyzed using Prism v.8.3.0 software (La Jolla, CA). The study was approved by the Institutional Review Board of the University of Utah. Results Out of the 80 samples from individuals without ZSD referred for EFA testing, 18% had normal fatty acid profile, 57% were receiving dietary supplements and 25% had elevated Triene/Tetraene ratio suggesting EFA deficiency. EFA deficiency was accompanied by low DHA only in two individuals without ZSD, whereas it was present in most of the samples from ZSD patients evaluated (5/7). None of the individuals without ZSD were deficient in plasmalogens. Moreover, when compared to individuals without ZSD with a normal FA profile, there was no significant difference observed with EFA deficiency or FA supplementation. Although our ZSD cohort is small, no correlation between EFA deficiency and plasmalogen levels was also seen in ZSD: 2 patients with milder phenotype had EFA deficiency but normal plasmalogens, 2 patients had EFA deficiency and low plasmalogens, 2 patients with low plasmalogens had low DHA without EFA deficiency, and 1 patient had low plasmalogens but normal EFA. Conclusions Plasmalogen quantitation in RBCs by LC-MS/MS is not significantly affected by EFA deficiency. Although more data is warranted to elucidate the correlation between plasmalogen levels and ZSD phenotype, plasmalogens can be within normal reference intervals in ZSD regardless of EFA status.

Vamifeport: Monography of the First Oral Ferroportin Inhibitor.

Over the last few years, several mechanisms that are involved in congenital diseases characterized by ineffective erythropoiesis have been described. Therefore, multiple new target drugs are being developed in preclinical models against the main regulators of normal erythropoiesis. Above all, the key mechanism that regulates systemic iron homeostasis, represented by the hepcidin-ferroportin axis, is considered to be the target for new therapies. The main hypothesis is that iron restriction, through blocking ferroportin (the unique iron transporter in mammals) in such diseases, ameliorates erythropoiesis. The action of vamifeport is different from the currently approved drugs in this setting since it acts straight on the ferroportin-hepcidin axis. The data presented in the sickle cell disease (SCD) Townes mouse model showed a preclinical proof-of-concept for the efficacy of oral ferroportin inhibitor. Vamifeport reduced hemoglobin concentration in red blood cells (RBCs) and diminished intravascular hemolysis and inflammation, improving hemodynamics and preventing vascular occlusive crises. On this basis, clinical trials were commenced in patients with SCD, non-transfusion-dependent (NTD) thalassemia and transfusion-dependent (TD) thalassemia. Preliminary data in NTD thalassemic patients also confirm the safety and efficacy in decreasing iron level. In conclusion, vamifeport represents a new option in the panorama of drugs targeting the hepcidin-ferroportin axis, but its efficacy is still under investigation as a single agent.

Adhesive and cohesive fracture of blood clots: Experiments and modeling

Blood clots represent living materials composed of a polymer network and an abundance of cells. They might fracture within the bulk material of the clot (cohesive fracture), at the interface between the clot and the surrounding tissue (adhesive fracture), or through a combination of both modes (hybrid fracture). The clot fracture within vascular systems and injury sites could lead to life-threatening conditions. Despite the significance, understanding and modeling the fracture behaviors of blood clots, including their dependence on mechanical loading and cellular components, remain in a nascent stage. In this study, we employ an integrated experimental-computational approach to comprehensively investigate the fracture behaviors of bovine blood clots. We explore various mechanical factors, substrates, and cellular components such as red blood cells (RBCs) and platelets. Our findings reveal that among various tissue substrates, blood clots exhibit the highest interfacial adhesion energy with muscle, and the lowest to the inner arterial lining, consistent with their biological function. Both interfacial adhesion energy and bulk fracture energy are rate-dependent, although they exhibit different dependencies. Also, RBCs and platelets have different effects on clot fracture. An increase in RBC content tends to toughen both adhesion and fracture of blood clots. However, an increase in platelet content enhances interfacial adhesion energy but lowers the bulk fracture energy. The platelet content also governs the shift from adhesive fracture to hybrid fracture. To model clot fracture, we developed two finite element models incorporating a coupled cohesive-zone and Mullins-effect approach to simulate pure shear fracture and peeling of blood clots. These models, validated through experimental data, elucidate the interplay between intrinsic fracture toughness, interfacial strength, and bulk energy dissipation during clot fracture. This study significantly advances our understanding of clot mechanics, providing valuable insights into the mechanics of similar living materials and the management of clot-related disorders such as hemorrhage and thrombosis.

Retrospective Analysis of Transfusion-Related Adverse Reactions: A 15-Month Study of a Single Center’s Experience

The aim of this study was to evaluate transfusion-related adverse reactions (TRARs). In this study, all adverse reactions (ARs) related to blood/blood product transfusions conducted between 01.01.2022 and 31.03.2023 at the Health Sciences University Türkiye, Adana City Training and Research Hospital were evaluated. In total, 97,926 records of blood and blood component transfusions were evaluated during the study period. The distribution of blood components used was as follows: 57,066 (58.2%) red blood cell concentrates, 27,345 (28%) fresh frozen plasma, 12,282 (12.5%) pooled platelet concentrates, 564 (0.6%) apheresis platelet concentrates, and 669 (0.7%) cryoprecipitates. In total, 40 AR reports were associated with transfusions. The probability levels of the relationship degrees of reactions for these 40 cases were as follows: 2 cases; not likely (5%); 32 cases; likely (80%); 2 cases; highly likely (5%); and 4 cases, unassessable (10%). All unwanted reactions were acute, and there were no delayed reactions. No transfusion reaction (TR) leading to death occurred. Of the patients who developed reactions, 60% (n=24) were female, and 40% (n=16) were male. The ages of patients with unwanted reactions ranged from 2 to 86 years, with a median age of 33. Among the cases with unwanted reactions, 8 were children (20%) and 32 were adults (80%). In our study, the frequency of allergic TR was 8.1 per 100,000 children and 32.6 per 100,000 adults. A statistically significant difference in the distribution of blood component types among cases based on the types of unwanted reaction was observed (p=0.003). In this retrospective evaluation of 15 months of data from a single center, 97,926 blood component transfusions were performed, and the prevalence of TRAR was 40.8 per 100,000 blood components.

Cellular and enzymatic features of thrombi in humans are vascular bed dependent

AbstractMechanisms behind vascular remodeling following thrombosis are unclear. Although acute arterial thrombosis in the cerebrovascular circulation has devastating consequences and requires immediate attention, the management of venous thromboembolism (VTE) varies significantly. Our goal was to determine the molecular signatures and cellular content of thrombus extracted using a catheter to gain insight into vascular remodeling. Twenty-five patients underwent catheter-directed thrombectomy (CDT); 13 for cerebrovascular accident (CVA), 8 for pulmonary embolism, and 4 for deep vein thrombosis. Protein and RNA were extracted from thrombi to enable immunoblotting, RNA sequencing, and quantification of gene expression. The time from symptom onset to thrombus extraction was 7.7 ± 1.9 hours for CVA and 109 ± 55 hours for VTE. Protein concentration, white blood cell content (monocytes), and red blood cell content were greater in venous thrombus than in arterial thrombus, whereas the platelet content was similar. Both venous and arterial thrombi contained several zinc endopeptidases belonging to the matrix metalloproteinase (MMP) family. MMP9 activity in venous thrombus was greater than arterial thrombus (61 ± 9 ng/mL per μg protein vs 25 ± 6 ng/mL per μg protein; P = .005). Arterial and venous thrombi displayed surprisingly different phenotypes, with biologically active enzymes promoting blood vessel remodeling and enzymatic activity proportional to thrombus age extracted from the veins. These mechanistic data may support the role of early CDT in venous circulation to avoid irreversible vascular remodeling.

Methotrexate accumulation in target intestinal mucosa and white blood cells differs from non-target red blood cells of patients with Crohn's disease.

Intracellular methotrexate polyglutamates (MTX-PGs) concentrations are measurable in red blood cells (RBCs) during MTX treatment. MTX-PG3 concentrations correlate with efficacy in patients with Crohn's disease (CD). Since RBCs are not involved in pathogenesis of CD and lack extended MTX metabolism, we determined MTX-PGs accumulation in peripheral blood mononuclear cells (PBMCs: effector cells) and intestinal mucosa (target cells) and compared those with RBCs as a potential more precise biomarker. In a multicentre prospective cohort study, blood samples of patients with CD were collected during the first year of MTX therapy. Mucosal biopsies were obtained from non-inflamed rectum and/or inflamed intestine. MTX-PGs concentrations in mucosa, PBMCs and RBCs were measured by liquid chromatography-tandem mass spectrometry. From 80 patients with CD, a total of 27 mucosal biopsies, 9 PBMC and 212 RBC samples were collected. From 12 weeks of MTX therapy onwards, MTX-PG3 was the most predominant species (33%) in RBCs. In PBMCs, the distribution was skewed towards MTX-PG1 (48%), which accounted for an 18 times higher concentration than in RBCs. Long-chain MTX-PGs were highly present in mucosa: 21% of MTX-PGtotal was MTX-PG5. MTX-PG6 was measurable in all biopsies. MTX-PG patterns differ between mucosa, PBMCs and RBCs of patients with CD.

Categorization of the Inevitable Causes of Blood and Components Wastage Detected in South Indian Urban Blood Centre

Background: Since there is no artificial substitute for human blood, it plays a vital role in the patient management in this era of modern medicine. Therefore the donated blood from a healthy donor is precious and must not be wasted without proper utilization. Blood wastage is a universal phenomenon which needs a careful approach with strict guidelines. The study aims at categorizing the various inevitable causes of wastage with an attempt to determine ways of preventing the loss due to non-utilization. Materials and Methods: A retrospective – cross sectional study was conducted in a newly started Stand-alone Blood Centre in South Indian Urban city between June, 2022 and June 2024.All the components including Whole Blood (WB), Packed Red Blood Cell Concentrate (PRBC), Platelet concentrate (PC) and Fresh Frozen Plasma (FFP) were included in the study. The reasons for blood and component wastage was noted down from the various Registers of the Blood Centre and all the data was analyzed using Microsoft Excel Spread Sheet. Results: A total of 2456 units of blood were collected. 5284 components were prepared from these which includes 42 units of Whole Blood, 2397 Packed Red Blood cells(PRBC), 2393 Fresh frozen Plasma(FFP), 452 Platelet Concentrate(PC).Overall discard rate was found to be 11.90%. PC discard rate was highest (49.34%) followed by WBU (19.04%), PRBC (13.01%) AND FFP (3.59%). The commonest cause for the discarding was expiry of the shelf life of blood bags (74.72%) followed by damaged bags (9.69%) and TTI’s (6.76%). Conclusion: Blood and its components wastage is an inevitable reality which needs to be approached as upmost priority. Zero wastage of blood and components may be targeted by recommendations like appropriate training of the blood bank staff, keeping negative group donors on reserve, strictly following FIFO policy while dispensing blood, whole blood unit collection may be minimized, encouraging Single Donor Platelets (SDP) by apheresis instead of Random Donor Platelets (RDP) preparation, Blood Utilization Committee to be made mandatory and permission for reciprocal sharing of blood components among blood banks.

Relationships of hematocrit concentration with dementia from a multiethnic population-based study.

Red blood cell (RBC) concentration impacts cerebrovascular disease, yet it is unclear whether RBC concentrations relate to dementia risk, particularly in racially/ethnically diverse cohorts. We investigated whether RBC concentrations associate with incident dementia risk in a diverse population of stroke-free individuals and explored whether cerebral small vessel disease (CSVD) mediates this relationship. A longitudinal observational analysis was performed using a population-based cohort of stroke-free, older adult participants (>50 years) from the Northern Manhattan Study (NOMAS) enrolled between 2003-2008. Participants received baseline hematocrit testing, MRI neuroimaging, and cognitive assessments at baseline and long-term follow-up. Associations of baseline hematocrit as a categorical variable (low, normal [reference], and high based on laboratory reference levels) with incident dementia were assessed using Cox models adjusting for relevant covariates. Separate analyses investigated whether MRI CSVD mediated these relationships. We studied 1207 NOMAS participants (mean age 71±9 years, 60% female, 66% Hispanic). Mean hematocrit was 41.2% (±3.8) with 16% of participants developing incident dementia. Lower hematocrit associated with increased dementia risk (adjusted hazard ratio 1.81 [1.01-3.23]) after adjusting for age, sex, race/ethnicity, education, APOE status, and comorbidities. High hematocrit was not associated with dementia risk. No interactions by sex or race/ethnicity were seen and baseline CSVD did not mediate relationships between hematocrit and dementia. Low hematocrit associated with dementia risk in our diverse population cohort. Further work is needed to assess mechanisms behind anemia's relationship with dementia to assess whether this can serve as a trackable, preventable/treatable risk factor for dementia.

Circulating lung-cancer-related non-coding RNAs are associated with occupational exposure to hexavalent chromium – A cross-sectional study within the SafeChrom project

BackgroundHexavalent chromium (Cr(Ⅵ)) is classified as a group 1 human carcinogen and increases the risk of lung cancer. Non-coding RNAs (ncRNAs) have key regulatory roles in lung cancer, but less is known about their relation to Cr(Ⅵ) exposure. ObjectivesWe aimed to 1) measure the expression of lung cancer-related circulating ncRNAs in exposed workers and controls; 2) assess associations between ncRNAs expression and Cr concentrations in red blood cells (RBC) and urine; and 3) evaluate correlations between the ncRNAs. MethodsThe study included 111 Cr(VI) exposed workers and 72 controls recruited from the SafeChrom project. Cr concentrations were measured in RBC (biomarker of long-term exposure) and urine (biomarker of short-term exposure) samples. Long ncRNA (lncRNA) and microRNA (miRNA) were extracted from plasma followed by deoxyribonuclease treatment, complementary DNA synthesis, and quantitative real‐time polymerase chain reaction using target-specific assays for three lncRNAs (H19, MALAT1, NORAD), and four miRNAs (miR-142-3p, miR-15b-5p, miR-3940-5p, miR-451a). ResultsExpression levels of lncRNAs MALAT1 and NORAD, and all four miRNAs, were significantly lower in Cr(VI) exposed workers compared with controls, and correlated significantly with RBC-Cr concentrations (rS = −0.16 to −0.38). H19 was non-significantly increased in exposed workers but significantly correlated with miR-142-3p (rS = −0.33) and miR-15b-5p (rS = −0.30), and NORAD was significantly positively correlated with all four miRNAs (rS = 0.17 to 0.46). In multivariate regression models adjusting for confounders, expressions of lncRNAs MALAT1 and NORAD and all miRNAs were still significantly lower in the exposed group compared with controls, and the expression decreased with increasing RBC-Cr concentrations. ConclusionsCr(VI) exposure was inversely and in a dose–response manner associated with the expression of circulating non-coding RNA, which suggests ncRNAs as potential biomarkers for Cr(VI)-induced toxicity. Correlations between miRNAs and lncRNAs suggest that they participate in the same lncRNA-miRNA-messenger RNA regulatory axes, which may play important roles in Cr(VI) carcinogenesis.

Multiphase patient-specific simulations to study fibrillation-induced thrombosis in the left atrial appendage

Thrombosis commonly develops in the left atrial appendage of patients with atrial fibrillation. The formation of blood clots in atrial appendage is a complex process, which depends on the shape of the appendage, the velocity of blood flow, the concentrations of red blood cells, platelets, and coagulation, among other factors. In this work, we present a new methodology to identify the key factors contributing to clot formation in the left atrial appendage during atrial fibrillation. The new methodology combines computed tomography imaging, computational fluid dynamics, mesh processing, and multiphase thrombosis modeling. We begin by running simulations to investigate flow patterns inside the left atrial appendages with realistic geometries. Our simulations suggest that at the entrance of the left atrial appendage, the flow forms vortices, which can intrude inside the appendage depending on the phases of the cardiac cycle. Next, we introduce blood coagulation and consider different scenarios corresponding to physiological values of blood flow velocity, geometry of the left atrial appendage, and hematocrit values. Numerical results suggest that the chances of clot formation are higher in the “cactus” geometry than in the “chicken-wing” one, in agreement with the literature. Furthermore, they suggest that slower flow circulation facilitates the development of a clot in the depth of the left atrial appendage. Slower blood movement also favors the procoagulant activity of platelets, while faster flow circulation enhances the procoagulant effect from erythrocytes. Finally, our simulations show that increased hematocrit upregulates the generation of fibrin polymer, regardless of flow velocity.

Effect of Terminalia Catappa Linn. Leaves Extract on Water Quality, Survival and Blood Profile of Betta sp.

Betta sp., also known as Siamese fighting fish, is renowned in the ornamental fish trade for its captivating colours and unique shapes, particularly among male specimens. Despite extensive research, challenges persist in meeting market demand for this species due to high mortality rates during production. Therefore, this study focused on determining the water quality properties (pH, dissolved oxygen, temperature), survival rates and blood profile of the Betta sp. by applying different concentrations of Terminalia catappa leaves (TCL) extracts: 0 (Control treatment), 480 (Treatment 1), 960 (Treatment 2), 1440 (Treatment 3) and 1920 (Treatment 4) ppm on three months old Betta splendens for 30 days. The experiment employed a completely randomized design (CRD) with three replications for each treatment. Results indicated that temperature and dissolved oxygen remained unaffected by varying concentrations of TCL, while pH exhibited a significant decrease with increasing concentration, ranging from 7.07 to 5.88. Notably, treatment 2 (pH 6.73) demonstrated a significant improvement in survival rate, achieving 100 % survival compared to the control (pH 7.07) with 46.67 % survival. Moreover, treatment 2 exhibited a significantly higher specific growth rate (0.85 % per day) compared to the control (0.04 % per day). Red blood cell (RBC) content also exhibited significant differences, with the highest RBC content (1.269 x 10^6 µL) observed at the highest TCL concentration (treatment 4, 1920 ppm). Therefore, the study concludes that the most optimal concentration of TCL, as determined from the research, was 960 ppm with a pH of 6.73. This concentration yielded the highest survival rate and growth performance for 3-month-old Betta splendens.

Numerical study of the effect of geometrical parameters of straight impellers on the flow and hemolysis performance of centrifugal blood pumps

Red blood cells are destroyed when the shear stress in the blood pump exceeds a threshold, which in turn triggers hemolysis in the patient. The impeller design of centrifugal blood pumps significantly influences the hydraulic characteristics and hemolytic properties of these devices. Based on this premise, the present study employs a multiphase flow approach to numerically simulate centrifugal blood pumps, investigating the performance of pumps with varying numbers of blades and blade deflection angles. This analysis encompassed the examination of flow field characteristics, hydraulic performance, and hemolytic potential. Numerical results indicated that the concentration of red blood cells and elevated shear stresses primarily occurred at the impeller and volute tongue, which drastically increased the risk of hemolysis in these areas. It was found that increasing the number of blades within a certain range enhanced the hydraulic performance of the pump but also raised the potential for hemolysis. Moreover, augmenting the blade deflection angle could improve the hemolytic performance, particularly in pumps with a higher number of blades. The findings from this study can provide valuable insights for the structural improvement and performance enhancement of centrifugal blood pumps.

Association between thrombus composition and first-pass recanalization after thrombectomy in acute ischemic stroke

BackgroundAchieving first-pass recanalization (FPR) has become the primary procedural objective during thrombectomy in acute ischemic stroke patients as it correlates with the best clinical outcome. Understanding factors contributing to FPR failures is essential to enhance FPR success rates. As the central target of thrombectomy, the thrombus itself may be a significant factor influencing FPR. ObjectivesThis study aimed to investigate the association between thrombus composition and FPR success rates. MethodsIn total, thrombi from 267 ischemic stroke patients were collected in the AZ Groeninge Hospital (Kortrijk, Belgium). Thrombus composition was determined via detailed histologic analysis of red blood cells (RBCs), fibrin, von Willebrand factor, platelets, leukocytes, citrullinated histone 3 (marker for neutrophil extracellular traps), and intracellular and extracellular DNA. FPR was defined as obtaining a modified thrombolysis in cerebral infarction (mTICI) score of 2c/3 after the first pass. ResultsAn mTICI score of 2c/3 was obtained in 180 patients, which was achieved via a successful FPR procedure in 126 cases or after multiple passes in 54 cases. Interestingly, thrombi from FPR cases had a different composition from thrombi that needed multiple passes to obtain an mTICI score of 2c/3. FPR thrombi contained significantly more RBCs (P = .0264), less fibrin (P = .0196), and less extracellular DNA (P = .0457). ConclusionOur results indicate that thrombi characterized by lower RBC content, higher fibrin levels, and increased extracellular DNA are less likely to result in an FPR. These results are important to guide future research aiming at improving procedures or technologies to obtain FPR rates in RBC-poor thrombi.

Endothelial calcium dynamics elicited by ATP release from red blood cells

Red blood cells (RBCs) exhibit an interesting response to hydrodynamic flow, releasing adenosine triphosphate (ATP). Subsequently, these liberated ATP molecules initiate a crucial interaction with endothelial cells (ECs), thereby setting off a cascade involving the release of calcium ions (Ca2+\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^{2+}$$\\end{document}). Ca2+\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^{2+}$$\\end{document} exerts control over a plethora of cellular functions, and acts as a mediator for dilation and contraction of blood vessel walls. This study focuses on the relationship between RBC dynamics and Ca2+\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^{2+}$$\\end{document} dynamics, based on numerical simulations under Poiseuille flow within a linear two-dimensional channel. It is found that the concentration of ATP depends upon a variety of factors, including RBC density, channel width, and the vigor of the flow. The results of our investigation reveals several features. Firstly, the peak amplitude of Ca2+\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^{2+}$$\\end{document} per EC escalates in direct proportion to the augmentation of RBC concentration. Secondly, increasing the flow strength induces a reduction in the time taken to reach the peak of Ca2+\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^{2+}$$\\end{document} concentration, under the condition of a constant channel width. Additionally, when flow strength remains constant, an increase in channel width corresponds to an elevation in calcium peak amplitude, coupled with a decrease in peak time. This implies that Ca2+\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^{2+}$$\\end{document} signals should transition from relatively unconstrained channels to more confined pathways within real vascular networks. This notion gains support from our examination of calcium propagation in a linear channel. In this scenario, the localized Ca2+\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^{2+}$$\\end{document} release initiates a propagating wave that gradually encompasses the entire channel. Notably, our computed propagation speed agrees with observations.

Predicting the onset of metabolic syndrome in a cohort study using a logistic regression model

Introduction: Metabolic syndrome (MetS) is a complex condition manifested as a group of metabolic disorders and is associated with the prevalence of certain diseases. Early prediction of MetS risk in the middle-aged population can be effective in controlling and preventing cardiovascular diseases. This study aimed to use logistic regression to predict metabolic syndrome and identify risk factors related to this condition. Method: This cohort study investigated factors associated with metabolic syndrome in the Mashhad study, which included a total of 11,570 participants. Factors that increase the relative risk of metabolic syndrome were evaluated using logistic regression, and predictive modeling was performed using logistic regression. Results: The results of the analysis using the logistic regression model showed that some factors, such as body mass index, history of high blood lipids, history of high blood pressure, and diabetes, increased the risk of metabolic syndrome. Various indicators, such as inactivity, high blood urea level, red blood cell hemoglobin content, aging, female gender, high levels of liver gamma-glutamyl transferase, and blood uric acid increase the risk of developing metabolic syndrome. Conclusion: It seems that body mass index, history of diabetes, and heart disease are related to the relative risk of developing the MetS syndrome compared to the other indicators, such as history of blood lipids, sedentary blood pressure, blood urea, uric acid, and hemoglobin content of red blood cells. These findings were obtained using the logistic regression model.

Ozone Therapy in the Integrated Treatment of Female Dogs with Mammary Cancer: Oxidative Profile and Quality of Life.

Considering the high frequency of malignant breast tumors, there is a growing search for new therapeutic strategies that control neoplastic growth and dissemination, combined with fewer adverse reactions. Therefore, this study evaluated the effects of ozone therapy in female dogs with mammary cancer undergoing chemotherapy treatment. Twenty-five canines diagnosed with malignant mammary neoplasia were divided into two groups: one treated with carboplatin alone (n = 11) and the other with carboplatin associated with ozone therapy (n = 14). Clinical and laboratory evaluations, mastectomy, analysis of the oxidative profile based on total antioxidant capacity (TAC) and serum concentrations of malondialdehyde (MDA), survival rate, and quality of life were performed. Animals in the ozone therapy group had higher concentrations of red blood cells and platelets, significantly improving the survival rate and quality of life. Furthermore, adverse reactions were less intense and frequent in this group, which was associated with an increase in TAC and a reduction in MDA. These results indicate that the combination of carboplatin and ozone therapy represents a promising complementary treatment for female dogs with mammary cancer, as it was associated with fewer adverse reactions and a better oxidative profile.

Water content for clot composition prediction in acute ischemic stroke.

Mechanical thrombectomy (MT) has become the gold standard care for treating acute ischemic stroke (AIS) due to large vessel occlusion. Emerging evidence suggests that understanding the composition of clots prior to intervention could be useful for the selection of neuroendovascular techniques, potentially improving the efficacy of treatments. However, current imaging modalities lack the ability to distinguish clot composition accurately and reliably. Since water content can influence signal intensity on CT and MRI scans, its assessment may provide indirect clues about clot composition. This study aimed to elucidate the correlation between water content and clot composition using human clots retrieved from stroke patients and experimentally generated ovine clots. This study involved an analysis of ten clots retrieved from patients with AIS undergoing MT. Additionally, we created ten red blood cells (RBC)-rich and ten fibrin-rich ovine blood clots, which were placed in a human intracranial vascular model under realistic flow conditions. The water content and compositions of these clots were evaluated, and linear regression analyses were performed to determine the relationship between clot composition and water content. The regression analysis in human stroke clots revealed a significant negative association between RBC concentration and water content. We also observed a positive correlation between water content and both fibrin and platelets in ovine blood clots. Conclusion.

#2907 Characterization of patients needing red blood cell transfusion after kidney transplant

Abstract Background and Aims After kidney transplant there is often need of red blood cell (RBC) transfusion because acute bleeding associated with surgery; or because multifactorial progressive anemization the days after. The aim of this work is to describe the characteristics of transfused kidney transplant recipients (KTR) and compare them to nontransfused controls. Method Retrospective observational study, reviewing the data from electronic medical records of patients receiving a kidney transplant in our hospital during 2022. Results During 2022, 160 kidney transplants were performed in adult people in our hospital and 66 (41.25%) KTR were transfused; some of them receiving the first red blood cell concentration (RBCC) during surgery (19.7%), the rest after surgery hospitalization because acute (10.6%) or progressive (69.7%) anemization. The total number of RBCC received was 1 in the 15% of transfused KTR, 2 in the 48%, 3 in the 8% and ≥ 4CH in the 29%. Among transfused KTR, the 13.6% kidney grafts came from living donors, 48.5% from Maastricht III, 36.4% from brain death and 1.5% from Maastricht II, whereas the kidney grafts of nontransfunded controls came from living donors (11.7%), Maastricht III (54.26%), encephalic death (32.98%) and Maastricht II (1.06%). The mean age of the transfused KTR was 62 years, 63.6% were males, 14.1% with ischemic heart disease, 6.3% with heart failure, moderate-severe valvular heart disease. The 12.12% were treated with acenocoumarol and the 25.7% with acetylsalicylic acid before the transplant hospitalization (whereas in nontransfunded controls the percentages were 10.6% and 21.3% respectively). Haemoglobin (Hb) levels previous to the surgery was lower in transfused KTR, presenting Hb <10 g/dl in the 10.6% of the recipients, whereas in nontransfunded controls was 2.1%. Moreover, ferritin levels were <100 ng/ml in 13.6% and transferrin saturation index was <20% in the 30.3% (whereas in nontransfunded controls it was 25.53% and 38.29% respectively). The mean of Hb before the transplant surgery in transfused KTR was 11.7 ± 1.4 g/dl, and before RBCC transfusion the median was 7.8 g/dl [7.6-8.1]. Conclusion Although more studies are needed, it is interesting to know the characteristics of the KTR that need RBC transfusion in order to asses measures (such us for example, Hb, iron … pretransplant adequate thresholds), in order to avoid if it is possible, unnecessary RBC transfusions.