Red Blood Cell Plasma Research Articles

Impact of Altitude on Erythrocyte Sedimentation Rate: A Cross-Sectional Study Using National Laboratory Data from Saudi Arabia.

The erythrocyte sedimentation rate (ESR) is a widely used haematological test that indirectly measures inflammation in the body. It is influenced by various factors, including age, sex, and physiological condition. Altitude is another critical factor due to its impact on red blood cell physiology and plasma protein composition. This study aims to evaluate how altitude influences ESR values in the Saudi Arabian population, considering demographic and clinical variables. This cross-sectional study analyzed data from 158,539 participants collected from 42 commercial laboratory branches across 13 administrative regions in Saudi Arabia from 1 January 2015 to 31 December 2022. Participants were categorized based on city altitude and demographic characteristics including body mass index (BMI), alanine transaminase (ALT), chronic kidney disease (CKD), glycated haemoglobin (HbA1c), and thyroid-stimulating hormone (TSH) level. Univariate and multivariate logistic regression models were used to assess the factors influencing elevated ESR. The study analyzed 158,539 participants, with an equal sex distribution (49.9%) and a mean age of 40 years. The adjusted model results showed a CKD prevalence of 3%, with a higher prevalence at lower altitudes (3.8% at 0-500 meters). ESR levels were significantly influenced by sex, age, altitude, and clinical measurements. Males were less likely to have elevated ESR than females (odds ratio (OR) = 0.470, 95% confidence interval (CI): 0.440-0.510, p < 0.001). Older age was a strong predictor of elevated ESR, with those aged 90+ at a fourfold higher risk (OR = 4.540, 95% CI: 1.410-14.548, p = 0.011). Higher altitude was associated with reduced ESR, with an odds ratio of 0.660 (95% CI: 0.560-0.769, p < 0.001) above 2000 meters. Altitude significantly impacts ESR values, highlighting the need for altitude-specific reference ranges to improve diagnostic accuracy in high-altitude regions. The results also emphasize the importance of considering demographic and clinical factors when interpreting ESR. These findings can guide clinicians in refining diagnostic algorithms and optimizing patient management strategies in diverse geographical settings.

Blood volume deficit in postural orthostatic tachycardia syndrome assessed by semiautomated carbon monoxide rebreathing

Abstract Purpose The semiautomated carbon monoxide (CO) rebreathing method has been introduced as a noninvasive and radiation-free blood volume estimation method. We tested whether the semiautomated CO rebreathing method can detect the blood volume deficit in postural orthostatic tachycardia syndrome (POTS). In addition, we explored the relationship between blood volume estimated from CO rebreathing and body impedance. Patients and methods We recruited 53 subjects (21 female patients with POTS, 19 healthy female participants, and 13 healthy male participants) to record blood volumes and hemodynamic data. Blood volumes were measured by CO rebreathing and segmental body impedance. Linear regression models to predict normal values of red blood cell volume (RBCV), plasma volume (PV), and total blood volume (BV) were developed. Percentage deviations from the predicted normal volumes were calculated. Results Patients with POTS had lower RBCV (25.18 ± 3.95 versus 28.57 ± 3.68 mL/kg, p = 0.008, patients with POTS versus healthy female participants), BV (64.53 ± 10.02 versus 76.78 ± 10.00 mL/kg, p &lt; 0.001), and BV deviation (−13.92 ± 10.38% versus −0.02 ± 10.18%, p &lt; 0.001). Patients with POTS had higher supine heart rate (HR) (84 ± 14 versus 69 ± 11 bpm, p &lt; 0.001) and upright HR (123 ± 23 versus 89 ± 22 bpm, p &lt; 0.001). We found a correlation between BV deviation and upright HR in patients with POTS (r = −0.608, p = 0.003), but not in healthy participants. Volumes from the CO rebreathing and body impedance were well correlated (r = 0.629, p &lt; 0.001). Conclusions The CO rebreathing method can detect BV deficit, as well as the RBCV deficit in patients with POTS. The negative correlation between BV deviation and upright HR indicates that hypovolemia is one of the pathophysiological causes of POTS. Correlations between body impedance and CO rebreathing volume suggest its usefulness for measurements of volume changes.

Dynamic evolution analysis and parameter optimization design of data-driven network infectious disease model

Background and Objective:globalization and population mobility have increased the spread of infectious diseases and challenged public health security. This paper proposes a complex network epidemic model with nonlinear incidence rate and quadratic transmission. The Turing pattern, sensitivity analysis and parameter identification of the epidemic model under different network structures are studied; Methods:this paper discusses the Turing pattern of the model under different network structures, and identifies the key parameters of the model through sensitivity analysis. The influence of network dimension on the spread of infectious diseases on random networks is also explored, and the problems of minimum path and minimum cover set of random networks are further discussed. We also carry out parameter identification experiments, adopt gradient descent algorithm to realize heterogeneous spatial fitting pattern of red blood cell plasma and simulate the transmission path of COVID-19 through Markov chain Monte Carlo fitting experiment, verifying the effectiveness of the model; Results:the necessary conditions for Turing instability on homogeneous and heterogeneous networks are found. On the heterogeneous lattice network, we observe the special patterns of equal density population. Sensitivity analysis shows that the higher the infection rate, the more infected people. On random networks, the higher the dimension, the better the effect of suppressing the spread of infectious diseases. Through comparison experiment, it is found that gradient descent algorithm has the best performance in parameter identification experiments. Red blood cell plasma fitting experiment reveals the spatial density distribution of infection rate; Conclusions:this study provides theoretical support for the prevention and control of infectious diseases, and the complex network model can simulate the transmission process of infectious diseases more accurately. Sensitivity analysis and parameter identification experiments reveal the key influencing factors of propagation and the role of network structure. The effectiveness of the model is supported by actual data, which is helpful for the government health departments to formulate scientific prevention and control strategies.

Effects of 90-Minute Football Match on Red Blood Indices in Sedentary Young Males

While exercise-induced haemorheological alterations are well-documented in various sports, the specific impact of a football match on red blood cell (RBC) parameters remains unknown. This study investigates the acute effects of a 90-minute football match on RBC indices in sedentary young males. After inclusion and exclusion criteria, twenty (20) moderately active, non-smoking male volunteers (mean age: 20.00 ± 0.4 years) participated in the study. Venous blood samples were collected pre- and post- football match to assess RBC count, haematocrit (HCT), and plasma volume (PV). Data generated were subjected to paired student's t-tests using SPSS, to compare values between pre- and post-match measurements. A p-value of less than 0.05 was considered indicative of statistical significance. The results showed a statistically significant decrease in haematocrit (HCT) and red blood cell count (RBC) after the match (p &lt; 0.05) when compared to pre-match values. This was accompanied by a significant increase in plasma volume (PV) (p &lt; 0.05), which was higher than pre-match values. These changes suggest that the physiological demands of the football match influenced blood parameters, likely due to fluid shifts and haemodilution during intense physical activity. These findings suggest potential implications for exercise physiology, diagnosis, and therapy in sports medicine.

Benzalkonium chloride induced acute toxicity and its multifaceted implications on growth, hematological metrics, biochemical profiles, and stress-responsive biomarkers in tilapia (Oreochromis mossambicus).

This study aimed to investigate the toxic effects of benzalkonium chloride (BAC) on Oreochromis mossambicus, a freshwater fish species. Probit analysis was used to determine the lethal concentration (LC50) of BAC for different exposure periods (24, 48, 72, and 96h). The viability of fish exposed to BAC was assessed using the general threshold survival models (GUTS) and confirmed with relevant datasets to evaluate model accuracy. Experimental groups of fish were exposed to BAC concentrations equivalent to 10% and 20% of the 96-h LC50 for 45days. The study revealed significant alterations in various parameters during sublethal BAC exposure. These effects included decreased specific growth rate (SGR), red blood cell count (RBC), hemoglobin (Hb) concentration, hematocrit (Ht) value, plasma protein, and albumin levels, as well as acetylcholinesterase (AChE) activities in both gills and liver. Additionally, an increase in gastrosomatic index (GSI), feed conversion ratio (FCR), plasma glucose and creatinine concentrations, alanine aminotransferase (ALT), aspartate aminotransferase (AST) enzymatic activities, catalase (CAT), superoxide dismutase (SOD), and malondialdehyde (MDA) levels were observed in the exposed fish's gills and liver. Furthermore, the study found that glutathione S-transferase (GST) and glutathione peroxidase (GPx) levels initially increased and then decreased in both gills and liver after exposure to BAC. Correlation matrix analysis, multivariate multiple regression (MMR), canonical correspondence analysis (CCA), integrated biomarker response (IBR), and biomarker response index (BRI) were utilized to assess the impact of BAC on fish, highlighting significant effects on multiple biomarkers in O. mossambicus following surfactant exposure. Thus, the study provides valuable insights into the toxic effects of BAC on this fish species, emphasizing the importance of monitoring such pollutants in aquatic environments.

The Relationship Between GAPDH Gene Polymorphism and Risk of Acute Coronary Syndrome in South Indians with Type 2 Diabetes Mellitus.

As glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is one of the regulators of carbonyl stress, a pathogenic mechanism for diabetic complications like acute coronary syndrome (ACS), the study aimed to investigate the relationship between GAPDH gene polymorphism, GAPDH activity in red blood cell (RBC), methylglyoxal (MG) levels in plasma and ACS risk in South Indians with type 2 diabetes mellitus (T2DM). This study comprised 150 T2DM with ACS as cases and 150 T2DM without ACS as controls. The GAPDH rs1136666, rs1060620 and rs1060619 gene polymorphisms were identified by TaqMan probe assays. The RBC GAPDH activity and plasma MG levels were estimated. Cases had significantly higher plasma MG levels and lower RBC GAPDH activity than controls (P < 0.001). The distribution of rs1060620 or rs1060619 alleles and genotypes significantly differed between groups. The rs1060620 AG (OR 0.55; 95% CI 0.33-0.92; P = 0.022) or rs1060619 CT (OR 0.51; 95% CI 0.31-0.83; P = 0.007) genotype was associated with reduced ACS risk, confirmed in the over-dominant genetic model. Haplotype analyses revealed that the GAT and CGC haplotypes were associated with increased (OR 28.37; 95% CI 3.82-210.49; P = 8.51 × 10-7) and decreased (OR 0.45; 95% CI 0.24-0.86; P = 0.014) ACS risk in T2DM patients, respectively. Lower GAPDH activity was observed in the TT and CT genotypes compared to the CC genotype of rs1060619 (P < 0.001). This work established that the GAPDH rs1060620 or rs1060619 gene polymorphisms are associated with ACS risk in South Indians with T2DM.

Early and Long-Term Results of Minimally Invasive Mitral Valve Repair in Young and Middle-Aged Patients

The aim. To analyze the early and long-term results of minimally invasive mitral valve repair in young and middle-aged patients and compare the outcomes with mitral valve repairs performed through standard sternotomy. Materials and methods. From 2016 to 2021, 128 patients with mitral insufficiency were operated in the Ukrainian Children’s Cardiac Center. Exclusion criteria included patients under 18 or over 59 years old and patients with concomitant pathology of the aortic valve, aorta, and coronary arteries. Results. In the investigated group, the average duration of cardiopulmonary bypass and aortic cross-clamping time was longer than in the comparative group. However, the average duration of mechanical ventilation, average time in theintensive care unit, and average length of hospitalization were shorter in the investigated group. Patients in the investigated group less frequently required red blood cell transfusion (5.6% vs. 14.6%) and plasma transfusion (9.4% vs. 14.6%). The percentage of postoperative complications was almost half lower in the investigated group (3.6% vs. 6.6%). None of the patients in the investigated group showed a severe degree of mitral insufficiency, while two patients in the comparative group had severe mitral insufficiency. Conclusions. Minimally invasive mitral valve repair is associated with a lower percentage of postoperative complications. Early and long-term observation results indicate the high effectiveness and safety of the minimally invasive method.

Abstract PO5-23-11: Elevated linoleic acid levels in red blood cells membrane predicts response to neoadjuvant chemotherapy in breast cancer patients

Abstract Introduction: Fatty acids (FA) consumed in the diet have been implicated in increasing the risk of breast cancer (BC). Humans have a wide variety of FAs, including saturated (SFA), monounsaturated (MUFA), and polyunsaturated (PUFA) FAs. PUFAs can be further classified into omega-3 (n-3) and omega-6 (n-6) PUFAs. While n-3 has been associated with reducing inflammation and promoting apoptosis in BC cells, n-6 has been linked to increased inflammation, oxidative stress, and the promotion of BC cell proliferation and treatment resistance. In healthy women, the n-3 content in mammary tissue correlates with n-3 content in red blood cells (RBCs). The FA profile of the RBC membrane provides an unbiased option to assess lipid intake and composition, reflecting long-term FA intake and providing an objective and sensitive measure of lipid intake and body fat deposits. Notably, BC patients have been found to display a high n-6:n-3 ratio in RBCs, which is associated with inflammatory and oxidative stress biomarkers. The neoadjuvant chemotherapy treatment (NACT) model presents a unique opportunity to study resistance mechanisms in non-metastatic BC patients. In this approach, the absence of tumor (pathologic complete response: pCR, or Residual Cancer Burden (RCB) = 0) after NACT indicates treatment sensitivity and better overall survival (OS). Objective: The objective of this study is to determine whether differences in FA profiles determined in the RBC membrane and plasma are associated with the response to NACT in non-metastatic BC patients. Methods: A prospective study was conducted, including non-metastatic BC patients scheduled to receive NACT. Blood samples were collected before the first cycle of NACT to measure plasma and RBC FA derivatives, SFAs, MUFAs, and PUFAs. The pathological complete response (pCR) and residual cancer burden (RCB) were assessed. Results: A total of twenty-eight BC patients were included in the study. When comparing pCR vs. no-pCR using total SFA, MUFA, and PUFA plasma samples, no significant differences were observed. However, in RBC, an increase in PUFA was associated with a higher rate of no-pCR (**p&amp;lt; 0.01). Furthermore, comparing omega-6 and omega-3 (both PUFA) levels, an increase in omega-6 was associated with no-pCR (**p&amp;lt; 0.01), while no significant differences were observed with omega-3. No differences were obtained in plasma samples for either omega-6 and omega-3. To determine which specific omega-6 PUFAs were responsible for the association with no-pCR, elevated levels of linoleic acid (LA) in RBC were found to be associated with no-pCR (**p&amp;lt; 0.01). Other omega-6 PUFAs, including gamma-linolenic acid (GLA), eicosadienoic acid (EDA), dihomo-gamma linolenic acid (DGLA), and arachidonic acid (ARA), showed no significant associations. Multivariate and regression analysis confirmed LA (C18:2 n-6, LA) as the most relevant FA when assessing RCB (0-1 vs. 2-3) in RBC membranes, but not in plasma. The receiver operating characteristic (ROC) curve analyzing LA levels in RBC showed an area under the curve (AUC) of 0.855 for RCB (sensitivity: 76.9%, specificity: 92.3%). Conclusions: To the best of our knowledge, this is the first study demonstrating a clear connection between RBC membrane FA composition, specifically LA concentration, and the pathological response in BC patients after NACT. The measurements taken in plasma did not show significant associations, suggesting that RBC membrane FA profile of could serve as a relevant prognostic biomarker for studying resistance mechanisms to NACT in early BC patients Table. Measured FAs in RBC membrane and plasma by pathologic complete response *Indicates p&amp;lt;0.05; abbreviations: pCR: pathological complete response; SD: standard deviation; yr: years; BMI: body mass index; HR: hormone receptor; HER2: human epidermal growth factor receptor type-2; NLR: neutrophil to lymphocyte ratio; HG: histological grade; RCB: residual cancer burden; NA: not applicable Citation Format: Benjamin Walbaum, César Sánchez, Francisco Acevedo. Elevated linoleic acid levels in red blood cells membrane predicts response to neoadjuvant chemotherapy in breast cancer patients [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO5-23-11.

Couette–Poiseuille flow of variable viscosity in a multilayered channel partially filled with a homogeneous anisotropic porous layer: Role of the glycocalyx in attenuating shear stress on endothelial cells

We present an analytical solution for the Couette–Poiseuille flow of variable viscosity in a multilayered channel partially filled with a homogeneous anisotropic porous layer. We establish a critical criterion that dictates the dominating factor when the flow is under the influence of shear and pressure gradient combined. This multilayered system resembles blood flow inside an artery where the fluid layer 1, fluid layer 2, and anisotropic porous layer describe the red blood cell layer, plasma layer, and glycocalyx layer, respectively. One of the novel features of this work is to understand the shear stress distribution on the liquid–porous interface (plasma membrane) and the bottom plate (endothelial cell layer) considering the variable viscosity of the fluid layer 1 while accounting for the anisotropic permeability of the porous medium. We use the obtained analytical solution to investigate the effect of the glycocalyx layer on the transmission of the fluid shear stress to the endothelial cell layer. We perceive that the shear stress distribution is more effective at the outer edge of the glycocalyx (plasma membrane) than the endothelial cell layer. On the other hand, the impact of the anisotropy on the shear stress distribution is more significant on the endothelial cell layer. This model is amenable to analytical solutions of the multilayered system considering the variable viscosity property of the blood and providing a framework for designing microfluidic systems that replicate biological glycocalyx, such as glycocalyx scaffolding.

Unsteady solute transport in Casson fluid flow and its retention in an atherosclerotic wall

In the current study, a mathematical model of convective solute transport and its retention in an atherosclerotic wall is examined. The artery wall is supposed to be permeable and has cosine-shaped stenosis caused by various sorts of abnormal growth or plaque formation. The flowing blood is modeled as the suspension of all red blood cells in plasma, thought to be Casson fluid. The Immersed Boundary Method (IBM) and the Marker and Cell (MAC) method are used to numerically solve the unsteady governing equations of motion along with the appropriate initial and boundary conditions. The final results of the quantitative studies contain the corresponding flow-field and solute distribution profiles for the full arterial length. The essential components are evaluated, including the wall shear stress, wall concentration, and concentration contours. According to simulation data, the permeability of the wall directly affects the solute transport within the therapeutic region. The yield stress does, however, increase flow resistance and decrease solute uptake within the tissue. The projected outcomes are remarkably in line with previously published findings, which supports the applicability of the model under investigation.

Study of the f-cell ratio using plasma dilution and albumin mass kinetics

BackgroundThe f-cell ratio of 0.91 is a conversion factor between the hematocrit measured in peripheral blood and the hematocrit obtained by separate measurements of the red blood cell mass and plasma volume. The physiological background of the f-cell ratio is unclear. MethodsData were retrieved from 155 intravenous infusion experiments where 15–25 mL/kg of crystalloid fluid diluted the blood hemoglobin and plasma albumin concentrations. The hemodilution was converted to plasma dilution using the peripheral hematocrit, and the volume of distribution of exogenous albumin was calculated in 41 volunteers who received 20 % or 5 % albumin by intravenous infusion. Finally, the kinetics of plasma albumin was studied during 98 infusion experiments with 20 % albumin. ResultsPlasma dilution based on hemoglobin and albumin showed a median difference of −0.001 and a mean difference of 0.000 (N = 2184), which demonstrates that these biomarkers indicate the same expandable vascular space. In contrast, exogenous albumin occupied a volume that was 10 % larger than the plasma volume indicated by the anthropometric equations of Nadler et al. and Retzlaff et al. The kinetic analysis identified a secondary compartment that was 450 mL in size and rapidly exchanged albumin with the circulating plasma. ConclusionsThe results suggest that the f-cell ratio is due to rapid exchange of albumin between the plasma and a non-expandable compartment located outside the circulating blood (possibly the liver sinusoids). This means that the hematocrit measured in peripheral blood correctly represents the ratio between the red cell volume and the circulating plasma volume.

Cholesterol and Sphingomyelin Uniquely Alter the Rate of Transthyretin Aggregation and Decrease the Toxicity of Amyloid Fibrils.

Transthyretin (TTR) is a small tetrameric protein that aggregates, forming highly toxic oligomers and fibrils. In the blood and cerebrospinal fluid, TTR can interact with various biomolecules, phospho- and sphingolipids, and cholesterol on the red blood cell plasma membrane. However, the role of these molecules in TTR aggregation remains unclear. In this study, we investigated the extent to which phosphatidylcholine (PC), sphingomyelin (SM), and cholesterol (Cho), important components of plasma membranes, could alter the rate of TTR aggregation. We found that PC and SM inhibited TTR aggregation whereas Cho strongly accelerated it. The presence of these lipids during the stage of protein aggregation uniquely altered the morphology and secondary structure of the TTR fibrils, which changed the toxicity of these protein aggregates. These results suggest that interactions of TTR with red blood cells, whose membranes are rich with these lipids, can trigger irreversible aggregation of TTR and cause transthyretin amyloidosis.

Prehemolytic impact of phenothiazine drugs on the attachment of spectrin network in red blood cells.

Chlorpromazine, thioridazine, and trifluoperazine are phenothiazine drugs that cause colloid-osmotic hemolysis of human erythrocytes by unknown mechanism. To clarify this mechanism, the impact of these drugs on the βsp (1.4 MHz) and γ1sp (9 MHz) dielectric relaxations was investigated. Each relaxation was shown to reduce its strength on the severing specific bridge that connects the spectrin network with the lipid membrane. For βsp relaxation, this is the spectrin-actin-glycophorin C bridge while for γ1sp relaxation this is the spectrin-ankyrin-band 3 bridge.

Pediatric Moderate and Severe Traumatic Brain Injury: A Systematic Review of Clinical Practice Guideline Recommendations.

Traumatic brain injury (TBI) is the leading cause of death and disability in children. Many clinical practice guidelines (CPGs) have addressed pediatric TBI in the last decade but significant variability in the use of these guidelines persists. Here, we systematically review CPGs recommendations for pediatric moderate-to-severe TBI, evaluate the quality of CPGs, synthesize the quality of evidence and strength of included recommendations, and identify knowledge gaps. A systematic search was conducted in MEDLINE®, Embase, Cochrane CENTRAL, Web of Science, and Web sites of organizations publishing recommendations on pediatric injury care. We included CPGs developed in high-income countries from January 2012 to May 2023, with at least one recommendation targeting pediatric (≤ 19 years old) moderate-to-severe TBI populations. The quality of included clinical practice guidelines was assessed using the AGREE II tool. We synthesized evidence on recommendations using a matrix based on the Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework. We identified 15 CPGs of which 9 were rated moderate to high quality using AGREE II. We identified 90 recommendations, of which 40 (45%) were evidence based. Eleven of these were based on moderate to high quality evidence and were graded as moderate or strong by at least one guideline. These included transfer, imaging, intracranial pressure control, and discharge advice. We identified gaps in evidence-based recommendations for red blood cell transfusion, plasma and platelet transfusion, thromboprophylaxis, surgical antimicrobial prophylaxis, early diagnosis of hypopituitarism, and mental health mangement. Many up-to-date CPGs are available, but there is a paucity of evidence to support recommendations, highlighting the urgent need for robust clinical research in this vulnerable population. Our results may be used by clinicians to identify recommendations based on the highest level of evidence, by healthcare administrators to inform guideline implementation in clinical settings, by researchers to identify areas where robust evidence is needed, and by guideline writing groups to inform the updating of existing guidelines or the development of new ones.

The genetic polymorphisms and activity of glyoxalase 1 as a risk factor for acute coronary syndrome in South Indians with type 2 diabetes mellitus

ObjectiveThe individuals’ genetic traits predispose them to a higher or lower risk of Type 2 diabetes mellitus (T2DM) and its complications, for example, acute coronary syndrome (ACS). As carbonyl stress is responsible for the pathogenesis and complications of T2DM, and glyoxalase 1 (GLO1) is the most crucial determinant of carbonyl stress, the study aimed to explore the association between GLO1 gene polymorphism, GLO1 activity in red blood cell (RBC), plasma methylglyoxal (MG) levels, and ACS risk in South Indian T2DM patients. MethodsA total of 150 T2DM patients with ACS as cases and 150 T2DM patients without ACS as controls were recruited in a case-control study. The rs4746, rs1049346 and rs1130534 of the GLO1 gene were analysed using TaqMan allele discrimination assay. The RBC GLO1 activity and plasma MG levels were measured. ResultsSignificantly lower RBC GLO1 activity and higher plasma MG levels were found in cases compared to controls (p < 0.001 and p = 0.008, respectively). The genotype and allele frequencies of rs1049346 significantly differed between cases and controls (p < 0.001). For rs1130534 and rs1049346, no significant difference was found. For rs1049346, the TT and CC genotypes were associated with higher (p = 0.002) and lower (p = 0.001) ACS risk, respectively, in various genetic models. The TT genotype of rs1049346 was associated with lower RBC GLO1 activity (p = 0.004) and higher MG level (p = 0.010). In haplotype analysis, higher ACS susceptibility with the TAT haplotype (p < 0.001) and lower ACS susceptibility with the TAC haplotype (p < 0.001) were observed. Also, lower RBC GLO1 activity was associated with the TAT haplotype (p = 0.002). ConclusionsThe rs1049346 of the GLO1 gene may be associated with ACS risk in South Indian T2DM patients, and the T and C allele might be essential precipitating and protective factors, respectively.

Separation of Cells From Plasma by Means of Ultrasonics

This paper presents an analysis of use of ultrasonic standing wave in cell separation from bodily fluids based on the example of erythrocyte separation from plasma. It describes movement of red blood cells in plasma under the influence of the acoustic field (whose forces result from interaction of red blood cells with plasma as the vibrating medium) and under the influence of resistance forces in Stokes’ and Oseen’s approximation. The general properties of solutions of the motion equation are given. The solutions for the parameters of the ultrasonic wave and blood cells which are interesting in terms of practical applications in medical diagnostics are discussed. Time constants of the cell transportation to the regions of stable equilibrium in the field of ultrasonic standing wave are estimated. The formulas which determine the time needed to obtain the assumed concentration increase in plasma in nodes and/or anti-nodes of the standing wave are derived.

The effects of temperature and salinity on the blood chemistry and survival of juvenile Atlantic tarpon Megalops atlanticus.

Atlantic tarpon Megalops atlanticus are highly migratory sportfish that support recreational fisheries throughout their range. In US waters, juveniles can be found in coastal and estuarine habitats along the Gulf of Mexico and Atlantic seaboard, with temperature limiting their northern latitudinal distribution. Juveniles may overwinter in these areas during the first several years of life. Low temperatures are known to cause mortality in adults, but the challenges of temperature are less understood for juveniles. Furthermore, salinity, which can change dramatically in these habitats, may have a synergistic effect with temperature. To examine the physiological effects of temperature and salinity on juvenile tarpon, wild fish were acclimated to a range of conditions that potentially occur in the northern range of their estuarine habitats. The haematology of juvenile tarpon was examined in two salinity (≤2 and ≥30 ppt) and temperature (15 and 25°C) treatments, followed by a low-temperature tolerance test. After 2 weeks in treatment conditions, blood samples were analysed for haematocrit, pH, red blood cell concentration, haemoglobin content and plasma osmolality. Increased plasma osmolality was observed in fish at low temperature (15°C compared to 25°C) and at high salinity (≥30 ppt compared to ≤2 ppt). Blood pH was increased at 15°C compared to 25°C, with the highest pH at 15°C and low salinity. Haemoglobin, haematocrit and red blood cell concentration were higher at 25°C than 15°C, with haemoglobin lowest at 15°C and low salinity. For the low-temperature tolerance test, all fish were acclimated to 15°C for 2 weeks, then transferred to separate tanks where temperature was gradually decreased at 0.9 ± 0.1°C/h until fish lost equilibrium. Fish at low salinity lost equilibrium more rapidly (1 ppt, 12.65 ± 0.46°C) than fish at high salinity (30 ppt, 11.26 ± 0.14°C). The results indicate juvenile tarpon are susceptible to low temperature, which is exacerbated by low salinity, findings useful in the assessment of juvenile tarpon overwintering habitat.

Simultaneous Viscosity Measurement of Suspended Blood and Plasma Separated by an Ultrasonic Transducer

Blood viscosity is influenced by several factors, including red blood cell (RBC) deformability, hematocrit (Hct), and plasma protein levels. To effectively isolate the individual contributions of several factors, it is necessary to simultaneously measure the viscosities of the blood and plasma. In this study, the viscosities of suspended blood and plasma were obtained sequentially by adopting an ultrasonic transducer for plasma separation and a co-flowing microfluidic channel for viscosity measurement. To improve the measurement accuracy of viscosity, the correction factor was obtained through experiments and numerical simulations, which was then inserted into the analytical expression for viscosity. To stabilize the pulsatile blood flow resulting from a micropump, the frequency (f) and voltage (v) were set to f = 300 Hz and v = 140 au, respectively. Flexible polyethylene tubing (i.d. = 500 µm, length = 40 mm) was connected to the microfluidic device as an air damper. Consequently, the coefficient of variance of the blood velocity decreased by up to 1%. As a demonstration, suspended blood (Hct = 20%, 30%, and 40%) was prepared by adding normal RBCs to autologous plasma. Compared with the previous method, the present method overestimates the viscosity values of both the fluids (i.e., suspended blood: 14–25% and plasma: 7–21%). The present method has the ability to sequentially measure the viscosities of suspended blood and plasma. The integrated system contributes to reducing blood-handling procedures (i.e., blood collection, blood loading into the syringe, and syringe installation into the syringe pump).

Infant blood concentrations of folate markers and catabolites are modified by 5,10-methylenetetrahydrofolate reductase C677T genotype and dietary folate source

BackgroundFolate intake and polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene may affect folate metabolism in infants. ObjectivesWe investigated the association between infant’s MTHFR C677T genotype, the dietary folate source, and concentrations of folate markers in the blood. MethodsWe studied 110 breastfed infants (reference) and 182 infants who were randomly assigned to receive infant formulas enriched with either 78 μg folic acid or 81 μg (6S)-5-methyltetrahydrofolate (5-MTHF) per 100 g milk powder for 12 wk. The blood samples were available at the ages of <1 mo (baseline) and 16 wk. MTHFR genotype and concentrations of folate markers and catabolites [i.e., para-aminobenzoylglutamate (pABG)] were analyzed. ResultsAt baseline, carriers of the TT genotype (vs. CC) had lower mean (SD) concentrations (all in nmol/L) of red blood cell (RBC) folate [1194 (507) vs. 1440 (521), P = 0.033) and plasma pABG [5.7 (4.9) vs. 12.5 (8.1), P < 0.001] but higher plasma 5-MTHF [33.9 (16.8) vs. 24.0 (12.6), P < 0.001]. Irrespective of the genotype, infant formula with 5-MTHF (vs. folic acid) caused a significant increase in RBC folate concentration [1278 (466) vs. 947 (552), P < 0.001]. In breastfed infants, plasma concentrations of 5-MTHF and pABG increased significantly by 7.7 (20.5) and 6.4 (10.5), respectively, from baseline to 16 wk. Infant formula that complies with the present EU legislation for folate intake increased RBC folate and plasma pABG concentrations at 16 wk (P < 0.001) than formula-fed infants. At 16 wk, plasma pABG concentrations remained ∼50% lower in carriers of the TT (vs. the CC) genotype among all feeding groups. ConclusionsFolate intake from infant formula according to the present EU legislation increased RBC folate and plasma pABG concentrations in infants to a greater extent than breastfeeding, particularly in carriers of the TT genotype. However, this intake did not completely abolish the between-genotype differences in pABG. Whether these differences have any clinical relevance, however, remains unclear. This trial was registered at clinicaltrials.gov as NCT02437721.

Abstract WP247: Amylin, A Diabetes-associated Amyloid-forming Peptide, Accumulates In Thrombi And On Red Blood Cells - A New Biomarker For Stroke?

Emergent large vessel occlusions result in severe ischemic stroke without appropriate treatment with thrombolysis and/or mechanical thrombectomy. Type-2 diabetes mellitus (T2DM) is a major risk factor in stroke, with 25% of ischemic attacks occurring in individuals with T2DM. T2DM diagnosis is also associated with poorer functional outcomes, prolonged hospitalizations, and increased risk of recurrent stroke. Amylin, a peptide co-secreted with insulin in pancreatic β-cells, is hypersecreted in T2DM and readily forms neurotoxic oligomers which deposit in brain parenchyma. Due to amylin’s role in T2DM and T2DM’s relationship to stroke, we anticipated an increased level of amylin would be deposited on red blood cells (RBCs) of stroke patients when compared to non-stroke patients. Additionally, we anticipated an increased level of amylin immunoreactivity (AIR) in clot lysates when compared to RBC lysates and plasma. Blood samples and thrombi ( n =47) were collected from patients undergoing mechanical thrombectomies for stroke while blood samples ( n =21) were collected from patients with non-stroke neurological conditions. Samples were lysed and assayed for total protein concentration and intensity of AIR. Amylin uptake coefficients (AUCs) demonstrating the proportionality of amylin deposited on RBCs compared to total circulating amylin were calculated. After normalizing to total protein concentration, analysis revealed a significantly increased level of AIR in stroke clots when compared to stroke and non-stroke plasma and RBC lysates (p&lt;0.001 for each). Additionally, a significant increase (p&lt;0.0073) in AUC was found in stroke versus non-stroke. In summary, amylin accumulates in thrombi and deposits on RBCs of stroke patients. Further research into amylin’s potential role in thrombus formation is justified. Future studies are also needed to determine if stroke severity is associated with amylin level in thrombi and if T2DM exacerbates amylin-stroke pathology.