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Role of Streptokinase as a Thrombolytic Agent for Medical Applications
Published in Pankaj Bhatt, Industrial Applications of Microbial Enzymes, 2023
Hamza Rafeeq, Muhammad Anjum Zia, Asim Hussain, Ayesha Safdar, Muhammad Bilal, Hafiz M. N. Iqbal
Thrombosis is blood clot formation in the blood vessels, and this is actually the result of an imbalance of hemostasis and its inhibitors (Rizzoli et al., 2013). Changes in the blood vessels result in thrombosis, especially if the blood flow is slow (Kikkert et al., 2014). Atherosclerosis is due to changes in blood vessels. The plaques are protrusions in blood vessels, and these plaques are made up of lipids and collagens made up of smooth muscles (Tadayon et al., 2015). Different cells, such as free fatty acids, cholesterol, and scar tissues present in the arterial walls, make the arteries constrict, making it difficult for blood to flow to the heart. Chest pain is caused by slowed blood flow, and heart attack results from complete blockage of blood. And the most prominent cause of death in the developed countries is thrombosis. Forty-five percent of total deaths are due to vascular diseases in the United States (Ali et al., 2016). Lifestyle and diet changes prevent thrombosis. High plasma lipid levels are due to an imbalanced diet, lack of physical activity, high blood pressure, and cigarette smoking (Ali et al., 2016). Figure 14.1 represents the mechanism of thrombus formation in a circulatory system.
Pharmaceutical Applications of Collagen
Published in Amit Kumar Nayak, Md Saquib Hasnain, Dilipkumar Pal, Natural Polymers for Pharmaceutical Applications, 2019
K. Sangeetha, A. V. Jisha Kumari, E. Radha, P. N. Sudha
Wound healing is a complex process in which the repaired tissues will regenerate through different overlapping phases of (a) blood clotting (hemostasis), (b) inflammation, (c) proliferation and (d) maturation (Martin and Leibovich, 2005). If the healing of wound will occur within 8–12 weeks it was termed as acute wound, and if the mending process was prolonged over a month to years then it was called as chronic wound (Dhivya et al., 2015). Generally, in a chronic wound, the process of healing was so long, and the wound gets easily infected, which will risk the patient morbidity and mortality. Even though a huge number of wound dressing material with commercial name were available in market an ideal chase for wound dressing was still a challenge for researchers and collagen plays a vital role in wound healing as it was the major component in furnishing connective tissues, encouraging the deposition and organization of newly formed collagen, and thereby increase mechanical integrity to strengthen wound will results in foster healing. Collagen-based biomaterials have the ability to stimulate specific cells such as macrophages and fibroblasts, create moisture environment suitable to recover the wound at a faster rate. Here some of the novel combinations of collagen-based wound dressing materials were discussed.
Mechanical Effects of Cardiovascular Drugs and Devices
Published in Michel R. Labrosse, Cardiovascular Mechanics, 2018
The response of blood to altered mechanics are triggered by flow abnormalities and foreign surfaces that activate the coagulation system. As discussed in more detail in Chapter 8, blood is sensitive to changes in flow. The coagulation or clotting system of blood system is designed for localized hemostasis or for stoppage of blood flow following injury. This response is designed to protect the host from injury and consists of a cascade of chemical reactions in which the signal is amplified at each step. There are two entries into this system, the intrinsic and extrinsic systems, both of which collapse to a common pathway, with the conversion of prothrombin to thrombin. The concept of the coagulation cascade has evolved to reflect the multiple roles that thrombin plays in both coagulation and platelet activation. Thrombin is the most potent physiological activator of platelets and also activates leukocytes and endothelial cells, which can aggregate and occlude vessels downstream.
Incorporation of tissue factor-integrated liposome and silica nanoparticle into collagen hydrogel as a promising hemostatic system
Published in Journal of Biomaterials Science, Polymer Edition, 2023
Zhuang Shi, Chengcheng Shi, Chengkun Liu, Haiyan Sun, Sihan Ai, Xiaodan Liu, Haoyu Wang, Yunsong Gan, Huajie Dai, Xiaoqiang Wang, Fang Huang
The body’s natural response to bleeding is to initiate sophisticated and concerted mechanisms of hemostasis involving a cooperation of endovascular and perivascular components. In the primary hemostasis stage, platelets promptly adhere to the bleeding site (mainly to subendothelial collagen and von Willebrand factor), and then undergo activation and aggregation at the site to form a hemostatic plug [5, 6]. In the secondary hemostasis stage, coagulation cascade is activated, either via the activation of coagulation protein factor XII by materials with negative charge to trigger the intrinsic pathway, or the activation of factor VII by membrane-anchored tissue factor (TF) to initiate the extrinsic pathway [7, 8]. Both pathways of secondary hemostasis lead to the downstream proteolytic activation of other factors and eventually the formation of fibrin clots [5–8]. In many emergent cases with a potential massive hemorrhage, however, the body’s inherent hemostatic mechanisms become insufficient, and this necessitates the administration of hemostatic materials to compensate, mimic or augment physiological hemostasis.
Computational modeling of hypercoagulability in COVID-19
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2023
Ge Zhu, Susree Modepalli, Mohan Anand, He Li
The human blood coagulation cascade is a complex biochemical process (Schenone et al. (2004)). The primary function of human blood coagulation is to minimize blood loss during vascular injury due to physical trauma. Hemostasis refers to the process by which the body controls blood loss after an injury by secreting enzymes to form a clot and cover the injury sites. The human body maintains homeostasis by maintaining balance among three major hemostatic processes: vasodilation, blood coagulation and clot dissolution. The excessive progress of any of these three hemostatic processes can lead to abnormal hemostasis and potentially fatal consequences. For example, lack of sufficient concentration of coagulation factors (hemophilia) or abnormal fibrinolysis (Francis (1989)) can lead to rapid blood loss (Zimmerman and Valentino (2013)) and excessive generation of prothrombotic factors can lead to undesired blood clotting (thrombosis)(Zoller et al. (1999)). Both hemophilia and thrombosis can lead to fatalities. As a result, maintaining hemostasis is key to maintaining healthy physiology.
Fabrication of thrombin loaded TEMPO-oxidized cellulose nanofiber-gelatin sponges and their hemostatic behavior in rat liver hemorrhage model
Published in Journal of Biomaterials Science, Polymer Edition, 2022
Md Sowaib Ibne Mahbub, Tamanna Sultana, Jae-Gyoung Gwon, Byong-Taek Lee
After injury, hemostasis (stopping bleeding) is the first stages of tissue healing to take place [1]. The tissue healing cascade involves four phases of hemostasis, inflammation, proliferation and remodeling [2]. To date, uncontrolled hemorrhage plays a leading role in morbidity and mortality due to surgical lacerations, puncture wounds, heterogeneous blunt trauma, etc. [3,4].