H∞-Feedback Control of Heparin-Controlled Blood Clotting Network for Cardiac Surgeries

This paper presents a solution methodology for H∞-feedback control design problem of Heparin controlled blood clotting network under the presence of stochastic noise. The formulaic solution procedure to solve nonlinear partial differential equation, the Hamilton-Jacobi-Isaacs equation with Successive Galrkin’s Approximation is sketched and validity is proved. According to Lyapunov’s theory, with solutions of the nonlinear PDEs, robust feedback control is designed. To confirm the performance and robustness of the designed controller, numerical and Monte-Carlo simulation results by Simulink software on MATLAB are provided.

A Case of Adverse Reaction to Booster Dose of COVID-19 Vaccination: Could D-Dimer Elevation Suggest Increased Clotting Risk?

We report the clinical case of a 40-year-old Italian woman, who soon after her booster vaccination with mRNA-1273 after the two previous vaccinations with BNT162b2, developed severe headache, high fever, and Musculo-skeletal pain. She went to the emergency department, where computerized tomography (CT) scans of chest and brain were performed, resulting in both negative for pathologic findings. On the contrary, white blood count was strongly lowered and D-dimer severely elevated. She improved after treatment with enoxaparin and the blood analyses returned in the normal range after ten days. This case supports the hypothesis that COVID-19 vaccines could increase blood clotting in some predisposed subjects. Therefore, we believe that robust and well-designed clinical trials, considering the evaluation of D-dimer levels, should be performed to eliminate any doubts on this issue.

Blood Flow Through a Catheterized Artery Having a Mild Stenosis at the Wall with a Blood Clot at the Centre

The blood flow through a catheterized artery having a mild stenosis at the wall together with a blood clot at the centre is studied in the current investigation.Stenosis can occur in vessels carrying blood to brain(i.e.,Carotid arteries),Renal arteries that supply blood to kidneys etc.The flow is refined in such vessels by application of catheter.We have used a Newtonian viscous fluid model and also distinct shapes of stenosis,(i.e.,symmetric and non-symmetric shapes)are considered for this study.The entropy generation togetherwith viscous dissipation is also taken into account for a complete description of heat transfer mechanism.Exact solutions are calculated for the problem subject to given“no slip conditions”.The results are discussed graphically.The velocity quickly increases for a non-symmetric stenosis as compared to a symmetric stenosis.When the height of mild stenosis increases and the channel becomes narrow then the velocity increases in the centre but it decreases with the stenosed wall.However,as the height of blood clotσincreases then the velocity of blood flow reduces with the wall having clot but it remains almost same with the stenosed wall.Streamlines are plotted to visualize the flow pattern.The trapping is symmetric for a symmetric stenosis shape but it changes to non-symmetric trapping when we have a non-symmetric shape of stenosis.

Intravenous-Accelerated Saline Particles to Unblock Partially Clogged Blood Vessels Using a Microcontroller

This research assesses the speed of saline fluid in vein vessels using venipuncture medical kit as well as DC submersive pumps that are being controlled by a microcontroller. The microcontroller is monitored and governed using a software IDE interface installed on a powerful laptop. Saline solution is being pumped through a medical syringe at variable speeds up to a maximum of 18.39 cm/second to the vein. The novel technique in this research is the usage of two pumps called Pump 1 and Pump 2. Pump 1 is used to physically model the flow of “blood” in human vein and the second pump (Pump 2) is used to generate the accelerated saline particles that are used to break the yellow grease that is placed on the inside of the vein’s wall. A tiny brush is briefly dipped into yellow grease, and then it is used to place one layer (one turn) of yellow grease on the inside of the vein’s wall, and then this procedure is repeated to place consecutive layers of yellow grease onto the inside of the wall of the vein vessel using a tiny brush. It was found that accelerated saline particles can in fact destroy fats that are built up inside the veins’ walls.

Anomalous reactivity of thermo-bioconvective nanofluid towards oxytactic microorganisms

The peristaltic flow of a non-Newtonian nanofluid with swimming oxytactic microorganisms through a space between two infinite coaxial conduits is investigated. A variable magnetic field is applied on the flow. The bioconvection flow and heat transfer in the porous annulus are formulated, and appropriate transformations are used, leading to the non-dimensionalized ruling partial differential equation model. The model is then solved by using the homotopy perturbation scheme. The effects of the germane parameters on the velocity profile, temperature distribution, concentration distribution, motile microorganism profile, oxytactic profile, pressure rise, and outer and inner tube friction forces for the blood clot and endoscopic effects are analyzed and presented graphically.It is noticed that the pressure rise and friction forces attain smaller values for the endoscopic model than for the blood clot model. The present analysis is believed to aid applications constituting hemodynamic structures playing indispensable roles inside the human body since some blood clotting disorders, e.g., haemophilia, occur when some blood constituents on the artery wall get confined away from the wall joining the circulation system.

Implantable blood clot loaded with BMP-2 for regulation of osteoimmunology and enhancement of bone repair

The treatment of large-area bone defects still faces many difficulties and challenges.Here,we developed a blood clot delivery platform loaded with BMP-2 protein(BMP-2@BC)for enhanced bone regeneration.Blood clot gel platform as natural biomaterials can be engineered from autologous blood.Once implanted into the large bone defect site,it can be used for BMP-2 local delivery,as well as modulating osteoimmunology by recruiting a great number of macrophages and regulating their polarization at different stages.Moreover,due to the deep-red color of blood clot gel,mild localized hyperthermia under laser irradiation further accelerated bone repair and regeneration.We find that the immune niche within the bone defect microenvironment can be modulated in a controllable manner by the blood clots implantation and laser treatment.We further demonstrate that the newly formed bone covered almost 95%of the skull defect area by our strategy in both mice and rat disease models.Due to the great biocompatibility,photothermal potential,and osteoimmunomodulation capacity,such technology shows great promise to be used in further clinical translation.

Impact of Blood Clot in Oocyte-Corona-Cumulus Complex during in vitro Fertilization and Embryo Transfer

Objective To study the impact of blood clots in the oocyte-corona-cumulus complexes （OCCC） during in vitro fertilization and embryo transfer （IVF-ET）.Methods The OCCCs were harvested from the patients undergoing long protocol ovarian hyperstimulation. The OCCCs with blood clots removed or not, were randomly grouped into A or B. The OCCCs without blood clots were group C （the control）.Results The patient＇s age, infertility duration, the average GN consumption, the average days of superovulation and an average number of harvested oocytes showed no significant difference in the 3 groups. The fertilization rate and 2PN rate in group A were the highest, which were 85.4% and 71.1%, respectively, followed by group C, which were 77.5% and 64.9%, respectively. The lowest fertilization rate and 2PN rate were in group B, 75.8% and 62.2%, respectively. Those in group A were significantly higher than those in groups B and C （P〈0.01）, while there was no significant difference between group B and group C. The implantation rates and pregnancy rates showed no significant difference in the 3 groups after transplantation, even if group A got the highest rate among the 3 groups. Conclusion Removing the blood clots in OCCC can improve the outcome of IVF-ET without increasing the cost and complexity of the operation.

Polyhexamethylene biguanide chemically modified cotton with desirable hemostatic,inflammation-reducing,intrinsic antibacterial property for infected wound healing

Medical cotton dressing is cheap and widely used in diversified fields,but in the application of promoting wound healing,the continuous research of multifunctional medical cotton dressing is still of great significance.Here,we developed a fresh type of antibacterial cotton dressing through a succinct strategy based on chemically anchoring polyhexamethylene biguanide(PHMB).Intriguingly,after PHMB modification,the cotton dressing exhibited outstanding antibacterial performance which could maintain>99.99%antibacterial rate after several treatments,including washing 50 times,repeated use 10 times,UV irradiation for 7 days,cationic dyes dying,and conditioned under 90℃water bath for 2 h.In addition,the water contact angle of cotton dressing increased dramatically from 0°to 111°,which could facilitate bacterial adhesion,thus further enhance the antibacterial efficiency,and easily remove the bacterial debris.Apart from that,the developed cotton dressing showed good cytocompatibility,promoted blood clotting and expression of platelets,and promoted the wound healing process in the infection intervened skin wound model.Taken together,this antibacterial cotton dressing with desirable blood clotting,sustained protection against bacterial infection and bacterial removal features shows the potential to be a candidate for infected skin wound healing.

Polyphosphate-crosslinked collagen scaffolds for hemostasis and alveolar bone regeneration after tooth extraction

Post-extraction bleeding and alveolar bone resorption are the two frequently encountered complications after tooth extraction that result in poor healing and rehabilitation difficulties.The present study covalently bonded polyphosphate onto a collagen scaffold(P-CS)by crosslinking.The P-CS demonstrated improved hemostatic property in a healthy rat model and an anticoagulant-treated rat model.This improvement is attributed to the increase in hydrophilicity,increased thrombin generation,platelet activation and stimulation of the intrinsic coagulation pathway.In addition,the P-CS promoted the in-situ bone regeneration and alveolar ridge preservation in a rat alveolar bone defect model.The promotion is attributed to enhanced osteogenic differentiation of bone marrow stromal cells.Osteogenesis was improved by both polyphosphate and blood clots.Taken together,P-CS possesses favorable hemostasis and alveolar ridge preservation capability.It may be used as an effective treatment option for post-extraction bleeding and alveolar bone loss.Statement of significance:Collagen scaffold is commonly used for the treatment of post-extraction bleeding and alveolar bone loss after tooth extraction.However,its application is hampered by insufficient hemostatic and osteoinductive property.Crosslinking polyphosphate with collagen produces a modified collagen scaffold that possesses improved hemostatic performance and augmented bone regeneration potential.