Red Cell Suspensions Research Articles

Anti –Inflammatory Activity of Propolis Trigona sp. Water Extract from North Lombok with Red Blood Cell Membrane Stability Method

Propolis is a bee product that can be used as an anti-inflammatory. Cultivation of propolis-producing bees is also carried out in North Lombok. However, propolis has not been utilized optimally by the people of North Lombok. Apart from that, testing of North Lombok propolis is still limited to the chemical content and antioxidant activity of propolis extracted with ethanol solvent. Therefore, this study aims to determine the activity and effective concentration of North Lombok propolis water extract as an anti-inflammatory using the red blood cell membrane stability method. Groups include control groups such as positive control (diclofenac sodium), negative control (distilled water), and test groups (propolis water extract concentrations of 10%, 12.5%, 15%, 17.5%, 20%, 22.5%, 25%, 27.5%, and 30%). In The first step human blood was centrifuged of human blood, and then part of the red blood cells (sediment) was taken and saline was added to obtain a red blood cell suspension. Next, mixing the test solution was carried out in the order of 0.5 ml of red blood cell suspension, then 0.5 ml of extract was added (0.1% w/v Na-diclofenac solution in the positive control, distilled water in the negative control), 1 mL of buffer solution and 2 mL of hyposaline solution, then homogenized. Each group was incubated at 37°C for 30 minutes, then centrifuged for 10 minutes at 3000 rpm. The supernatant was taken, and the absorbance was read with a UV-Vis spectrophotometer at 560 nm. Next, the percentage value of red blood cell hemolysis protection was calculated. The data obtained were tested statistically using One-way ANOVA and post-hoc (LSD) tests SPSS version 29. The results showed that propolis water extract concentrations were 10%, 12.5%, 15%, 17.5%, 20%, 22.5%, 25%, 27.5%, and 30% have anti-inflammatory activity because they can increase the stability of the red blood cell membrane with a percentage of hemolysis protection of respectively 57.92%, 59.99%, 60.99%, 61.99%, 64.31%, 69.59%, 75.07%, 79.77% and 84.45%. Propolis water extract concentrations of 10%, 12.5%, 15%, 17.5%, 20%, 22.5%, and 25% had anti-inflammatory effects that were not significantly different from the positive control (p>0.05). The 27.5 % and 30% concentrations had a higher percent hemolysis protection value than the positive control (p<0.05).

“Comparative evaluation of cytotoxicity of three herbal endodontic irrigants at three intervals of time” – An in vitro study

Aim: The aim of the study was to evaluate and compare the cytotoxicity of 25% of neem leaf extract (Azadirachta indica), 20% of guava leaf extracts (Psidium guajava), and 20% of cinnamon extract (Cinnamomum zeylanicum) irrigants at three intervals of time. Methodology: Four groups were formed (n = 15), Group 1 (control group) – normal saline solution, Group 2 – 25% of neem extract, Group 3 – 20% of guava extract, and Group 4 – 20% of cinnamon extract. Each group was further divided into three subgroups based on intervals (n = 5). Subgroup A – at 10 min, Subgroup B – at 20 min, and Subgroup C – at 30 min. One hundred microliters of each irrigant was added to 2 mL of the diluted red blood cells suspension obtained from a human volunteer. Hemoglobin (Hb) estimation was done with an automated hematology analyzer after incubating the test samples at 10, 20, and 30 min intervals. Results: The reduction in the mean Hb values was not statistically significant in the normal saline, guava, and cinnamon groups. However, in the neem extract group, the mean Hb values reduced significantly at P < 0.001. Among the subgroups, Subgroup A (10 min) showed the least cytotoxicity. Conclusion: In the present study, 20% guava extract had the lowest cytotoxicity and cytotoxicity increased with time. Hence, 20% guava extract can be used as an alternative to conventional irrigants as it has been shown to have the least cytotoxicity.

Impact of Intraoperative Blood Transfusion on Cerebral Injury in Pediatric Patients Undergoing Congenital Septal Heart Defect Surgery

Background: The components of donor blood themselves have the potential to initiate a systemic inflammatory response and exacerbate neuroinflammation, resulting in subsequent cerebral injury. The aim of this study was to establish the role of transfusion in the development of cerebral injury during the correction of congenital heart defects in children. Material and Methods: A total of 78 patients aged from 1 to 78 months, with body weights ranging from 3.3 to 21.5 kg, were investigated. Biomarkers of cerebral injury and systemic inflammatory response were studied at three time points. First: prior to the surgical intervention. Second: after the completion of cardiopulmonary bypass. Third: 16 h after the conclusion of the surgery. Results: The strongest correlation was found for S-100-β protein with the volume of transfusion at the second (Rho = 0.48, p = 0.00065) and third time points (Rho = 0.36, p = 0.01330). Neuron-specific enolase demonstrated a similar trend: Rho = 0.41 and p = 0.00421 after the completion of cardiopulmonary bypass. Conclusions: The use of red blood cell suspension and its dosage per kilogram of body weight correlated with the biomarkers of cerebral injury and systemic inflammatory response with moderate to significant strength.

The effect of a low-level yellow laser on improving the stability of stored whole blood.

To explore if low-level laser 589nm may stabilise stored whole blood and red blood cell suspension in vitro. The interventional study was conducted from November 2021 to April 2022 at the Postgraduate Medical Physics Laboratory, Mustansiriyah University, Baghdad, Iraq, and comprised blood samples from healthy adults. The samples were obtained put in tubes containing anticoagulant citrate-phosphate dextrose-adenine. Each sample was divided into eight equal aliquots and stored for 21 days at 4ºC. Of the 8 aliquots, 4 were takebn as controls, while the other 4 were irradiated by 589nm laser beam with a radiation dose of 50J/cm² for 15min. Stability test measured by the percentage of haemolysis of an overnight stored red blood cell in saline solution was done on days 0, 7, 14 and 21 for non-irradiated and radiated aliquots. Data was analysed using SPSS 24. Eight subjects (4 males and 4 females) were included, with mean age 21±3 years (range: 19-24 years). Whole blood samples showed a significant reduction in haemolysis by 40%, 20% and 42% compared to the control samples at days 0, 7 and 14, respectively (p<0.05). Red blood cell suspension showed a significant reduction in haemolysis by 9% compared to the control samples only at day 21 (p<0.05). Low-level laser 589nm beam at 50J/cm² radiation dose was more effective on the stability of stored whole blood than the red blood cell suspension.

In vitro comparison of low-power diode pumping solid-state laser radiation at 589 and 650 nm on red blood cells suspension viscosity, stability, and deformability.

To investigate the effect of diode-pumped solid-state laser irradiation with yellow 589nm and red 650nm wavelengths on rheological parameters in vitro. The comparative study was conducted between November 2021 and April 2022 at the at the Postgraduate Medical Physics Laboratory, Mustansiriyah University, Baghdad, Iraq, and comprised blood samples from healthy adult volunteers. The samples were divided into 4 aliquots. The first was preserved as a control sample, while the other 3 were exposed to a diode-pumped solid-state laser, delivering the beam for 589nm and 650nm wavelengths at radiation dose 15, 22.5, 33.5J/cm2 for 20, 30 and 45 minutes, and with each laser having a 50mW output power and a 4 mm2 spot diameter. Data was analysed using SPSS (version 24). There were 6 subjects aged 18-60 years. There was no significant difference in the viscosity values between laser wavelengths (p>0.05). Compared to the laser wavelength of 650nm, irradiation with a 589nm wavelength at the same dose resulted in a significant reduction (p<0.009) in deformability. The rigidity index of red blood cell suspension was reduced the most at a radiation dose of 22.5J/cm2 for both lasers compared to the control samples. No significant variations were found in suspended erythrocyte viscosity (p>0.05). The wavelength with 589nm lasers showed more effective influence than its 650nm counterpart in improving the rheological parameters of blood viscosity and erythrocytes deformability.

Predictive Value of Thromboelastography for Postoperative Blood Loss in Infants Undergoing Cardiac Surgery

Thromboelastography (TEG) has emerged as a critical tool in promptly identifying the risk of postoperative bleeding, especially in infants and young children undergoing cardiac surgery. By meticulously analyzing TEG parameters, clinicians gain a profound understanding of patients&amp;apos; coagulation status, enabling timely intervention to minimize and manage postoperative bleeding risks. The present study adopts a rigorous, prospective, and observational approach to explore the relationship between intraoperative TEG test results and postoperative blood loss. Furthermore, it aims to assess the potential of intraoperative TEG testing as an early predictor of postoperative bleeding in high-risk pediatric patients. In this process, a key focus is placed on perioperative red blood cell suspension and platelet transfusion volume, as well as their association with TEG testing outcomes. Our findings reveal a significant correlation between the volume of red blood cell suspension and platelet transfusion and the MA value derived from TEG testing. The MA value, a pivotal indicator in TEG test results, represents the maximum clotting strength. Notably, during perioperative red blood cell suspension and platelet transfusion, the MA value often exhibits corresponding changes. These changes not only reflect improvements in coagulation function but also provide clinicians with an objective basis for evaluating the effectiveness of blood transfusion. However, despite the notable impact of blood transfusion on MA values, our study did not detect statistically significant associations between blood transfusion and other TEG parameters, including TEG-ACT values, α-Angle, and LY30. This absence of significant associations may be attributed to the differential effects of various transfusion components on the coagulation process, as well as the influence of confounding factors such as patient age, comorbidities, and surgical procedure type.

The Relationship Between Perioperative Blood Product Use and the Incidence of Postoperative Renal Injury in Infants Undergoing Cardiac Surgery

Cardiac Surgery Associated Acute Kidney Injury (CS-AKI) is a serious complication that occurs in patients following cardiac surgery. It is characterized by the rapid decline in kidney function, leading to potential long-term kidney damage or even kidney failure. CS-AKI is a significant health concern, as it not only prolongs hospital stays and recovery time but also increases the risk of mortality. This study, conducted as a prospective observational study, aimed to investigate the relationship between perioperative blood product use and the incidence of postoperative acute kidney injury (AKI) in infants and young children undergoing cardiac surgery. It examined the perioperative use of these blood products and its association with the occurrence of AKI. The findings of this study revealed a significant association between the use of red blood cell suspension and platelets and the development of postoperative AKI. This suggests that the administration of these blood products during cardiac surgery may increase the risk of kidney injury in infants and young children. However, it is important to note that the study did not find a statistically significant association between plasma transfusion volume and the incidence of AKI. This suggests that while the use of certain blood products may contribute to the risk of AKI, the volume of plasma transfused does not seem to have a significant impact. The findings of this study provide valuable insights into the perioperative management of infants and young children undergoing cardiac surgery. It underscores the importance of carefully considering the use of blood products during surgery and taking necessary measures to minimize the risk of AKI.

Aortic Valve Stenosis Causes Accumulation of Extracellular Hemoglobin and Systemic Endothelial Dysfunction.

Whether aortic valve stenosis (AS) can adversely affect systemic endothelial function independently of standard modifiable cardiovascular risk factors is unknown. We therefore investigated endothelial and cardiac function in an experimental model of AS mice devoid of standard modifiable cardiovascular risk factors and human cohorts with AS scheduled for transcatheter aortic valve replacement. Endothelial function was determined by flow-mediated dilation using ultrasound. Extracellular hemoglobin (eHb) concentrations and nitric oxide (NO) consumption were determined in blood plasma of mice and humans by ELISA and chemiluminescence. This was complemented by measurements of aortic blood flow using 4-dimensional flow acquisition by magnetic resonance imaging and computational fluid dynamics simulations. The effects of plasma and red blood cell (RBC) suspensions on vascular function were determined in transfer experiments in a murine vasorelaxation bioassay system. In mice, the induction of AS caused systemic endothelial dysfunction. In the presence of normal systolic left ventricular function and mild hypertrophy, the increase in the transvalvular gradient was associated with elevated eryptosis, increased eHb, and increased plasma NO consumption; eHb sequestration by haptoglobin restored endothelial function. Because the aortic valve orifice area in patients with AS decreased, postvalvular mechanical stress in the central ascending aorta increased. This was associated with elevated eHb, circulating RBC-derived microvesicles, eryptotic cells, lower haptoglobin levels without clinically relevant anemia, and consecutive endothelial dysfunction. Transfer experiments demonstrated that reduction of eHb by treatment with haptoglobin or elimination of fluid dynamic stress by transcatheter aortic valve replacement restored endothelial function. In patients with AS and subclinical RBC fragmentation, the remaining circulating RBCs before and after transcatheter aortic valve replacement exhibited intact membrane function, deformability, and resistance to osmotic and hypoxic stress. AS increases postvalvular swirling blood flow in the central ascending aorta, triggering RBC fragmentation with the accumulation of hemoglobin in the plasma. This increases NO consumption in blood, thereby limiting vascular NO bioavailability. Thus, AS itself promotes systemic endothelial dysfunction independent of other established risk factors. Transcatheter aortic valve replacement is capable of limiting NO scavenging and rescuing endothelial function by realigning postvalvular blood flow to near physiological patterns. URL: https://www.clinicaltrials.gov; Unique identifiers: NCT05603520 and NCT01805739.

Extracellular vesicles derived from stored red blood cell suspensions enhance invasion and migration of lung cancer cells by miR1246 and miR150-3p.

Aged red blood cell (RBC) transfusions in lung cancer patients are often related to cancer recurrence and shorter lifespans. Extracellular vesicles (EVs) accumulated in stored RBC suspensions may be one of the important influential factors. This study aims to investigate how EVs derived from RBC suspensions affect the progress of lung cancer through the most enriched microRNAs (miRNAs) previously reported in our research. EVs derived from stored RBC suspensions in Weeks 1, 3 and 5 were harvested via ultracentrifugation. Lung adenocarcinoma H1975 cells were co-cultured with EVs and transfected with miR1246 and miR150-3p mimics to evaluate alterations in their proliferation, invasion and migration abilities in vitro. Proteomics and bioinformatics were performed to predict the signalling pathway related to invasion and migration of H1975, which were verified by western blotting (WB) and flow cytometry. EVs derived from stored RBC suspensions in Weeks 3 and 5 could significantly enhance the invasion and migration ability of H1975 cells and also increase the expression of miR1246 and miR150-3p. After transfection with miR1246 and miR150-3p mimics, invasion, migration and proliferation of H1975 cells were obviously enhanced. Proteomics analysis demonstrated that EVs co-cultivation and miRNA transfection groups were both enriched in cell adhesion molecules. WB and cytometry indicated that integrin beta-1 (ITGB1) and Rap1b were increased. EVs derived from stored RBC suspensions can enhance invasion and migration ability of lung cancer cells via the most accumulated miR1246 and miR150-3p, which may increase the expression of ITGB1 through Rap1 signalling pathway.

Further insights into steady three-dimensional MHD Sakiadis flows of radiating-reacting viscoelastic nanofluids via Wakif’s-Buongiorno and Maxwell’s models

AbstractKeeping in mind the stress relaxation tendency of many viscoelastic multi-phase flows (e.g., polymer solution flows and transport phenomena of red cell suspensions within blood media), the present research investigation intends principally to develop a realistic model for revealing properly the aspects of reacting-radiating Maxwell nanofluids during their laminar boundary layer flows in the steady regime over a horizontal impermeable surface under a transversal magnetic influence. For this purpose, the principal leading differential formulation is derived theoretically by linking Wakif’s-Buongiorno approach with Maxwell’s model. By invoking fundamentally the general boundary layer assumptions and the passive control strategy for the nanoparticles, the governing PDEs’ formulation is simplified accordingly and then stated properly for the case of the convective heating condition at the impermeable bi-stretching surface. By executing a feasible non-dimensionalization technique, the monitoring ODEs’ system is achieved successfully, whose solutions are presented precisely in different illustrative scenarios using Richardson’s extrapolation method. After carrying out successfully several validating tests, it is demonstrated that the weakly viscoelastic feature has generally a slight delaying effect on the nanofluid motion. This dynamical weakening can be reinforced more with the generation of thermal energy by intensifying the external magnetic field source. Additionally, these physical factors show an intensifying influence on the surface drag forces. However, a dropping impression is seen for the local heat transfer at the contact surface. Contrary to the broadening impact of the radiative heat transfer as well as the convective heating and thermophoresis mechanisms on the thermal and mass boundary layer regions, it is witnessed that the first-order chemical reaction mechanism and Brownian’s motion exhibit a shrinking impact on the mass boundary layer region.

Viscoelasticity of suspension of red blood cells under oscillatory shear flow

We present a numerical analysis of the rheology of a suspension of red blood cells (RBCs) for different volume fractions in a wall-bounded, effectively inertialess, small amplitude oscillatory shear (SAOS) flow for a wide range of applied frequencies. The RBCs are modeled as biconcave capsules, whose membrane is an isotropic and hyperelastic material following the Skalak constitutive law. The frequency-dependent viscoelasticity in the bulk suspension is quantified by the complex viscosity, defined by the amplitude of the particle shear stress and the phase difference between the stress and shear. SAOS flow basically impedes the deformation of individual RBCs as well as the magnitude of fluid-membrane interactions, resulting in a lower specific viscosity and first and second normal stress differences than in steady shear flow. Although it is known that the RBC deformation alone is sufficient to give rise to shear-thinning, our results show that the complex viscosity weakly depends on the frequency-modulated deformations or orientations of individual RBCs but rather depends on combinations of the frequency-dependent amplitude and phase difference. The effect of the viscosity ratio between the cytoplasm and plasma and of the capillary number is also assessed.

Change in Osmotic Pressure Influences the Absorption Spectrum of Hemoglobin inside Red Blood Cells.

Absorption spectra of red blood cell (RBC) suspensions are investigated in an osmolarity range in the medium from 200 mOsm to 900 mOsm. Three spectral parameters are used to characterize the process of swelling or shrinkage of RBC-the absorbance at 700 nm, the Soret peak height relative to the spectrum background, and the Soret peak wavelength. We show that with an increase in the osmolarity, the absorbance at 700 nm increases and the Soret peak relative height decreases. These changes are related to the changes in the RBC volume and the resulting increase in the hemoglobin intracellular concentration and index of refraction. Confocal microscopy and flow cytometry measurements supported these conclusions. The maximum wavelength of the Soret peak increases with increasing osmolarity due to changes in the oxygenation state of hemoglobin. Using these spectrum parameters, the process of osmosis in RBCs can be followed in real time, but it can also be applied to various processes, leading to changes in the volume and shape of RBCs. Therefore, we conclude that UV-Vis absorption spectrophotometry offers a convenient, easily accessible, and cost-effective method to monitor changes in RBC, which can find applications in the field of drug discovery and diagnostics of RBC and hemoglobin disorders.

A case of hemolytic-uremic syndrome that developed in a 5-year-old child due to acute intestinal infection with hemocolitis

Purpose: to demonstrate a case of hemolytic-uremic syndrome (HUS) in a 5-year-old child associated with an acute intestinal infection of unknown etiology, occurring with hemocolitis. Results. During clinical and laboratory observation, edematous syndrome, oligoanuria, severe microangiopathic hemolytic anemia (decrease in hemoglobin, haptoglobin, increase in Lactate dehydrogenase), thrombocytopenia, consumption coagulopathy, hyperazotemia, acute kidney injury (AKI) according to KDIGO grade 2 (increase in serum creatinine more than 2 times) developed. As part of complex therapy with balanced crystalloid solutions with stimulation of diuresis, it was possible to achieve rapid restoration of diuresis on the 2nd day of hospital stay without the use of renal replacement therapy; he also received antibiotics, anticoagulants, transfusion of fresh frozen plasma and red blood cell suspension. Hyperazotemia was relieved within 5 days, as was thrombocytopenia. The follow-up recovery of renal function showed.

Changes in the electrical and viscoelastic parameters of erythrocytes in patients with manifestations of metabolic syndrome, COVID-19 convalescents, when exposed to citicoline in an in vitro experiment

Aim. To study changes in the electrical and viscoelastic parameters of erythrocytes using the method of dielectrophoresis in patients with manifestations of the metabolic syndrome who underwent COVID-19, when exposed to the drug citicoline in an in vitro experiment to reduce the severity of microcirculatory disorders.&#x0D; Materials and methods. 31 men were examined with manifestations of metabolic syndrome (50.6±9.9 years), COVID-19 convalescences, within 8 to 12 months after the disease, the diagnosis was confirmed by PCR, ELISA. The electrical and viscoelastic parameters of erythrocytes were studied by dielectrophoresis twice: the initial levels of indicators were determined and after 30 minutes of exposure with after 30 minutes of exposure to a solution of the drug Ronocyte (oral solution with the active substance citicoline sodium – 104.50 mg., which is equivalent to 100.00 mg citicoline at a concentration of 0.01 µl per 0.3 µl of red blood cell suspension in 0.3M sucrose solution (pH 7.36).&#x0D; Results. Exposure of erythrocyte suspension of patients with Ronocyte solution led to change in the levels of electrical, viscoelastic parameters: an increase in the average cell diameter (p=0.0003), the proportion of discocytes (p=0.0004), the amplitude of cell deformation at high frequencies of the electric field (p=0.000002), cell capacity (p=0.000007), the velocity of erythrocytes to the electrodes (p=0.003), dipole moment (p=0.002), polarizability at 106 and 0.5×106 Hz (p=0.000019 and p=0.0015, respectively), relative polarizability (p0.05) and, conversely, to reduce summarized rigidity (p=0.000003), viscosity (p=0.000002), electrical conductivity (p0.000001), aggregation indices (p=0.00003), destruction at frequencies of 106 Hz (p=0.003), 0.5x106 Hz (p=0.00002), 0.1×106 Hz (p0.00001), polarizability at low frequencies of the electric field (p=0.02). Under the influence of the drug, the equilibrium frequency of erythrocytes shifted to the low-frequency range compared to the initial values (p0.0000001). The revealed changes indicate an increase in the surface charge of erythrocytes, their ability to deform, and cell resistance under the action of citicoline.&#x0D; Conclusion. For the first time, the effect of the drug with the active substance citicoline, improving the rheological properties of erythrocytes, was discovered. Preparations with the active substance - citicoline should be considered promising for conducting a full-fledged clinical study to study the reduction of circulatory disorders at the microcirculatory level in patients with manifestations of metabolic syndrome who have undergone COVID-19 coronavirus infection.

Effects of cerium oxide nanoenzyme-gelatin methacrylate anhydride hydrogel in the repair of infected full-thickness skin defect wounds in mice

Objective: To investigate the effects of cerium oxide nanoenzyme-gelatin methacrylate anhydride (GelMA) hydrogel (hereinafter referred to as composite hydrogel) in the repair of infected full-thickness skin defect wounds in mice. Methods: This study was an experimental study. Cerium oxide nanoenzyme with a particle size of (116±9) nm was prepared by hydrothermal method, and GelMA hydrogel with porous network structure and good gelling performance was also prepared. The 25 μg/mL cerium oxide nanoenzyme which could significantly promote the proliferation of human skin fibroblasts and had high superoxide dismutase activity was screened out. It was added to GelMA hydrogel to prepare composite hydrogel. The percentage of cerium oxide nanoenzyme released from the composite hydrogel was calculated after immersing it in phosphate buffer solution (PBS) for 3 and 7 d. The red blood cell suspension of mice was divided into PBS group, Triton X-100 group, cerium oxide nanoenzyme group, GelMA hydrogel group, and composite hydrogel group, which were treated with corresponding solution. The hemolysis of red blood cells was detected by microplate reader after 1 h of treatment. The bacterial concentrations of methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli were determined after being cultured with PBS, cerium oxide nanoenzyme, GelMA hydrogel, and composite hydrogel for 2 h. The sample size in all above experiments was 3. Twenty-four 8-week-old male BALB/c mice were taken, and a full-thickness skin defect wound was prepared in the symmetrical position on the back and infected with MRSA. The mice were divided into control group without any drug intervention, and cerium oxide nanoenzyme group, GelMA hydrogel group, and composite hydrogel group applied with corresponding solution, with 6 mice in each group. The wound healing was observed on 3, 7, and 14 d after injury, and the remaining wound areas on 3 and 7 d after injury were measured (the sample size was 5). The concentration of MRSA in the wound exudation of mice on 3 d after injury was measured (the sample size was 3), and the blood flow perfusion in the wound of mice on 5 d after injury was observed using a laser speckle flow imaging system (the sample size was 6). On 14 d after injury, the wound tissue of mice was collected for hematoxylin-eosin staining to observe the newly formed epithelium and for Masson staining to observe the collagen situation (the sample size was both 3). Results: After immersion for 3 and 7 d, the release percentages of cerium oxide nanoenzyme in the composite hydrogel were about 39% and 75%, respectively. After 1 h of treatment, compared with that in Triton X-100 group, the hemolysis of red blood cells in PBS group, GelMA hydrogel group, cerium oxide nanoenzyme group, and composite hydrogel group was significantly decreased (P<0.05). Compared with that cultured with PBS, the concentrations of MRSA and Escherichia coli cultured with cerium oxide nanoenzyme, GelMA hydrogel, and composite hydrogel for 2 h were significantly decreased (P<0.05). The wounds of mice in the four groups were gradually healed from 3 to 14 d after injury, and the wounds of mice in composite hydrogel group were all healed on 14 d after injury. On 3 and 7 d after injury, the remaining wound areas of mice in composite hydrogel group were (29±3) and (13±5) mm2, respectively, which were significantly smaller than (56±12) and (46±10) mm2 in control group and (51±7) and (38±8) mm2 in cerium oxide nanoenzyme group (with P values all <0.05), but was similar to (41±5) and (24±9) mm2 in GelMA hydrogel group (with P values both >0.05). On 3 d after injury, the concentration of MRSA on the wound of mice in composite hydrogel group was significantly lower than that in control group, cerium oxide nanoenzyme group, and GelMA hydrogel group, respectively (with P values all <0.05). On 5 d after injury, the volume of blood perfusion in the wound of mice in composite hydrogel group was significantly higher than that in control group, cerium oxide nanoenzyme group, and GelMA hydrogel group, respectively (P<0.05). On 14 d after injury, the wound of mice in composite hydrogel group basically completed epithelization, and the epithelization was significantly better than that in the other three groups. Compared with that in the other three groups, the content of collagen in the wound of mice in composite hydrogel group was significantly increased, and the arrangement was also more orderly. Conclusions: The composite hydrogel has good biocompatibility and antibacterial effect in vivo and in vitro. It can continuously sustained release cerium oxide nanoenzyme, improve wound blood perfusion in the early stage, and promote wound re-epithelialization and collagen synthesis, therefore promoting the healing of infected full-thickness skin defect wounds in mice.

Modeling of three-dimensional blood flow in microchannels using a two-fluid method

This work presents a novel two-fluid method based on our recently proposed viscosity model for red blood cells (RBCs)—for simulating three-dimensional (3D) blood flow in a microchannel of dimension comparable to the diameter of red blood cells and larger. Toward this, whole blood is assumed as a suspension of red blood cells in blood plasma, with each phase considered as interpenetrating continua having its separate mass and momentum conservation equations. The proposed approach-based performance study is presented after comprehensively validating it with experimental data for blood flow in a uniform, sudden expansion-constriction, and Y-shaped bifurcated rectangular microchannels over—an extensive range of size (25–330 μm), flow rates (11.8 μl/h–30 ml/h), and inlet hematocrit (0%–45%). The proposed approach effectively captures significant biophysical and biomechanical insights into blood flow. It highlights a migration of red blood cells toward the center of the microchannel and the formation of a cell-free layer near the wall. Notably, with the introduction of constriction and expansion in the microchannel, it predicts a fivefold enhancement of the cell-free layer. The Fahraeus and Fahraeus–Lindquist effects are also demonstrated in microchannels, with less than 300 μm characteristic dimensions. These findings are consistent with experimental evidence. In addition to experimentally evident phenomena, our simulations unveil several additional flow phenomena and features of blood flow in the microchannel. It is observed that the presence of confluence (merging flow) is more disturbing to the blood flow than the presence of diverging bifurcations (splitting flow). Furthermore, after the confluence, velocity profiles exhibit a local peak that persists up to the microchannel outlet. Primary contribution of this work lies in the proposal of a two-fluid method for simulating 3D blood flow in complex geometries. This approach provides a comprehensive understanding of blood flow dynamics in microchannels and can be applied to optimize dimensions and geometries during the initial phases of plasma separation microdevices development.

Effects of immediate and delayed infusion of residual physical blood on coagulation function, intraoperative bleeding, and hemostasis time in aortic dissection surgery under cardiopulmonary bypass

This study aims to assess the differences in coagulation function, intraoperative bleeding and hemostasis time resulting from immediate versus delayed infusion of residual physical blood in patients undergoing cardiopulmonary bypass for aortic dissection. From January 2018 to January 2021, the data of 122 patients diagnosed with acute Stanford type A aortic dissection and treated at Taihe Hospital Affiliated Hospital of Hubei University of Medicine were retrieved and assessed. They were then divided into two groups according to different treatments: a research group and a control group. The research group received a delayed infusion of residual physical blood intraoperatively, while the control group underwent immediate infusion. Various indicators of coagulation, encompassing activated partial thromboplastin time, prothrombin time, thrombin time, and fibrinogen levels, along with hemoglobin levels, utilization of blood products such as red cell suspension, plasma, platelets, and cryoprecipitate, as well as the volume of bleeding, total fluid intake and output, and durations of hemostasis, surgery, and anesthesia, were compared between the two groups. After surgery, coagulation and hemoglobin levels, which were initially similar between the two groups, were found to be significantly improved, with the research group showing superior outcomes (p &lt; 0.05). Additionally, patients in the research group required significantly fewer blood products, experienced reduced bleeding and total body fluid exchange and had markedly shorter durations of hemostasis, surgery and anesthesia compared to those in the control group (p &lt; 0.05). Pre-infusion adjustment of coagulation function before residual whole blood infusion effectively improves coagulation, reduces bleeding and fluid imbalance, and shortens hemostasis time during aortic dissection surgery with cardiopulmonary bypass. This approach not only reduces transfusion-related risks and improves postoperative recovery but also plays a significant role in optimizing blood management.

Comparison of restrictive and liberal red blood cell suspension transfusion and analysis of influencing factors on prognosis of premature infants.

To investigate the influence of restrictive and liberal red blood cell suspension (RBCs) transfusions on the prognosis of premature infants and to analyze the influencing factors to provide a reference for the transfusion strategy of preterm infants. Retrospective analysis was conducted on 85 cases of anemic premature infants treated in our center, including 63 cases in the restrictive transfusion group and 22 in the liberal transfusion group. RBCs transfusions were effective in both groups, and there were no statistically significant differences in post-transfusion hemoglobin and hematocrit between the two groups (P>0.05). The outcome events: the duration of ventilatory support was statistically prolonger in the restrictive group compared with the liberal group (P<0.001); however, the differences in mortality, the increased weight before discharge, and length of stay in the hospital within the two groups were not statistically significant (P=0.237, 0.36 and 0.771, respectively). Univariate survival analysis showed that age, birth weight, Apgar 1 min and Apgar 10 min scores were the influencing factors for death, with P values of 0.035, 0.004, <0.001, and 0.013, respectively; COX regression analysis showed that Apgar 1 min score was an independent factor of the survival time of preterm infants (P=0.002). Compared with the restrictive transfusion group, liberal transfusion patients presented a shorter duration of ventilatory support, which is more beneficial to the prognosis of premature infants.

Occurrence of kell blood group among individuals with ABO and Rh (D) blood groups in Awka and Asaba, Nigeria

Antigens on the surface of the red blood cells are used to determine their blood group. The major blood groups in Nigeria are ABO and Rh (D). Globalization and trans-continental marriages might have thrown up some other blood group in Nigeria. This study identified the occurrence of kell blood group among individuals with ABO and Rh (D) blood groups in Awka and Asaba, Nigeria. One hundred and forty-two participants were recruited randomly for the study. A ml of blood sample collected from each participant was washed in phosphate buffered saline (PBS) thrice and a 3% red cell suspension of each participant’s blood was used to determine their blood groups by their agglutination reactions with anti-A, anti-B, Anti-D and anti-K antibodies. The presence or absence of agglutination in any or combinations of the reactions was used to identify the blood groups. The agglutination reactions showed that 106 (74.6%) were O Rh (D) positive; 2 (2.8%) were O Rh (D) Negative; 18 (12.7%) were A Rh (D) positive, 2 (1.4%) were A Rh (D) Negative; 12 (8.5%) were B Rh (D) Positive; none was B Rh (D) Negative while 3(2.1%) were kell blood group. Two individuals with expression of kell antigen on their red cell were of O Rh (D) positive blood while the third individual was of A Rh (D) positive. The finding that 2.1% of the studied population are kell blood group was an indication that individuals with expression of kell antigen on their red cells resides in Nigeria.

Risk Factors for Post-Operative Multi-Drug-Resistant Organism Bacterial Infection in Patients With Stanford Acute Type A Aortic Dissection.

Background: To explore the risk factors for multi-drug-resistant organism (MDRO) infection in patients with Stanford acute type A aortic dissection (ATAAD). We conducted a retrospective cohort study using the data of post-operative patients with ATAAD in our hospital. Patients and Methods: This study included 82 post-operative patients with ATAAD in the past decade. They were divided into a MDRO group (n = 31) and a non-MDRO group (n = 51) according to whether they had acquired multi-drug-resistant (MDR) bacterial infection. Multivariable logistic regression was used to analyze the risk factors for MDR infections in patients with ATAAD. Results: The incidence of multi-drug-resistant bacterial infection was 37.80%. Seventeen factors, including hospital stay (p = 0.007), utilization of third-generation cephalosporins (p = 0.0068), antibiotic species of exposure (p = 0.0002), leukocyte-depleted red blood cell suspension dosage (p < 0.0001), fresh frozen plasma dosage (p < 0.0001), application of blood purification (p = 0.0493), and the total antibiotic days of exposure (p = 0.0001) diverged between the two groups (all p < 0.05). The logistic regression analysis revealed that the utilization of third-generation cephalosporins (odds ratio [OR], 2.32; 95% confidence interval [CI], 1.01-5.33; p = 0.0478), antibiotic species of exposure (OR, 5.76; 95% CI, 1.45-22.83; p = 0.0128), leukocyte-depleted red blood cell suspension dosage (OR, 12.43; 95% CI, 2.71-57.07; p = 0.0012), and fresh frozen plasma dosage (OR, 5.05; 95% CI, 1.18-21.56; p = 0.0286) were independent variables for MDRO infections. Among the 23 drug-resistant bacteria detected, Acinetobacter baumannii was the main pathogen. Conclusions: Our study shows that the utilization of third-generation cephalosporins, antibiotic species of exposure, leukocyte-depleted red blood cell suspension dosage, and fresh frozen plasma dosage were independent risk factors for post-operative multi-drug-resistant infection in patients with ATAAD. Acinetobacter baumannii occupied the largest share of resistant bacteria that induce infection in post-operative patients with ATAAD.