Hemostatic materialsHemostatic agen

Hemostatic materials
Hemostatic agents are being increasingly used in various
procedures such as hepatic, cardiovascular, spinal, and
orthopedic surgeries where hemorrhage control is essential
to avoid severe blood loss [87,88]. Suturing is conventionally applied to stop bleeding but it is not effective for
controlling rapid bleeding in many procedures. Therefore,
hemostats are used during surgeries for fast and effective control of bleeding. These hemostatic agents should
be safe, easy-to-apply as well as provide fast blood clotting. Hemostatic materials are classified into two main
categories: mechanical and active agents [29]. Mechanical
hemostatic agents stop bleeding by generating a mechanical barrier to the blood flow and can be used in forms
of sponges, sheets, powders, or particles. Some examples of the commercially available mechanical hemostatic
agents include Gelfoam (bovine gelatin, Baxter Inc.), Instat
(bovine collagen, Ethicon, Inc.), and Surgicel (oxidized
cellulose, Ethicon, Inc.) [61]. Active hemostatic agents
contain active biological components such as thrombin,
which can participate in blood clotting when applied to the
injured sites [29]. Combination of mechanical and active
agents has been shown to enhance the hemostatic efficacy
[61].
Mineral zeolite materials such as QuikClot (Z-Medica,
Wallingford, CT) have had a significant impact on trauma
care in clinical applications [89—91]. Mineral zeolite materials absorb liquid in the wound area, thereby increasing
the concentration of coagulants to induce hemostasis. The
activity of zeolite materials leads to an exothermic reaction in wound bed, which has been addressed by embedding
zeolite in a surgical mesh so it can be used as a compress
to absorb water less exothermically by using ion exchange
technique and prehydration [92,93]. Zeolite materials are
inexpensive, stable, easy-to-use, and have shown to have
both hemostatic and antibacterial properties [89]. In a clinical study, QuikClot was found to control bleeding in 92% of
the 103 documented cases with 100% of the cases performed
by first responders [94].
Hemostatic materials can be formed by combining one
or two coagulation cascades or hemostatic proteins including thrombin [95], collagen [96], chitosan [97,98], and fibrin
[4,99] as well as non-protein materials such as oxidized
cellulose [96,100] and PEG [100]. These hemostats have
been used in various forms for surgical applications including
matrix [96,101], patch [102,103] or liquid [95,99]. The major
challenges associated with the clinical use of these hemostatic materials include their high cost and non-effective
bleeding control [104].
To address these challenges, micro and nanoparticles
have been used as hemostatic agents to control blood loss.
For example, in a recent study, cationic hydrogel particles based on N-(3-a-aminopropyl)methacrylamide (APM)
were synthesized via inverse suspension polymerization and
used as hemostatic agents (Figure 1A) [105]. In vitro studies confirmed the formation of blood aggregation, which
was due to the high swelling ratio of the hydrogel particles (>1000%) as well as their high positive charge. The
capability of the engineered particles for rapid hemostasis
in vivo was also demonstrated by using a tail amputation rat
model (Figure 1B and C) and an ovine liver laceration model
(Figure 1D and E) [105].
Some research groups have focused on developing hemostatic materials based on functionalized nanoparticles
capable of aggregating platelets from blood flow [106—109].
For example, Ravikumar et al. created hemostatic nanomaterials through the surface functionalization of liposomes
with 150 nm diameters with three peptides including von
Willebrand factor (vWF)-binding peptide (VBP), collagenbinding peptide (CBP) and cyclic-Arg—Gly—Asp (cRGD)
peptide [107]. It was shown that liposomes containing
VBP and CBP could facilitate platelet-mimetic adhesion
and cRGD functionalized liposomes enhanced the aggregation of platelets onto themselves. Therefore, combination
of all three peptides provided a dual hemostatic function of aggregation and adhesion [107]. In another study,
Bertram et al. engineered functionalized nanoparticles
with the capabilities for binding to active platelets to
enhance their aggregation rate and consequently stop
bleeding [106]. A single emulsion evaporation technique was used to synthesize nanoparticles with the
diameter of 170 nm consisted of poly(lactic-co-glycolic
acid)-poly-L-lysine (PLGA-PLL) copolymer conjugated with
RGD functionalized PEG (Figure 2 A and B). The interaction of engineered nanoparticles with active platelets was
assessed in vitro by using a platelet adhesion and aggregation assay. These synthetic hemostatic nanoparticles also
reduced bleeding after intravenous injection in an injured
site in a rat artery by distributing throughout the clot
(Figure 2C—E). It was also shown that the nanoparticles were
effectively cleared within 24 h after infusion, demonstrating

Kết quả (Việt) 1:

Hemostatic vật liệuHemostatic đại lý đang đang ngày càng được sử dụng trong nhiềuthủ tục như hepatic, tim mạch, cột sống, vàphẫu thuật chỉnh hình nơi xuất huyết kiểm soát là rất cần thiếtđể tránh mất máu nghiêm trọng [87,88]. Suturing thường được áp dụng để ngừng chảy máu nhưng nó không phải là hiệu quả nhấtkiểm soát nhanh chóng chảy máu trong nhiều thủ tục. Do đó,hemostats được sử dụng trong quá trình phẫu thuật nhanh chóng và hiệu quả kiểm soát chảy máu. Cho nên các đại lý hemostaticđược an toàn, dễ dàng áp dụng cũng như cung cấp nhanh chóng máu đông máu. Hemostatic vật liệu được phân loại thành hai chínhthể loại: cơ khí và hoạt động đại lý [29]. Cơ khíhemostatic đại lý cầm máu bằng cách tạo ra một rào cản cơ khí để dòng chảy máu và có thể được sử dụng trong các hình thứcbọt biển, tấm, bột hay hạt. Một số ví dụ của hemostatic cơ khí thương mại có sẵnĐại lý bao gồm Gelfoam (bò gelatin, Baxter Inc), Instat(bò collagen, Ethicon, Inc.), và Surgicel (ôxi hóacellulose, Ethicon, Inc) [61]. hoạt động đại lý hemostaticchứa các thành phần sinh học hoạt động như thrombin,đó có thể tham gia vào máu đông máu khi áp dụng cho cácCác trang web bị thương [29]. Sự kết hợp của cơ khí và đang hoạt độngCác đại lý đã được chứng minh để tăng cường hiệu quả hemostatic[61].Zeolite khoáng sản vật liệu như QuikClot (Z-Medica,Wallingford, CT) đã có một tác động đáng kể về chấn thươngChăm sóc trong các ứng dụng lâm sàng [89-91]. Zeolite khoáng sản vật liệu hấp thụ chất lỏng trong vùng vết thương, do đó tăngthe concentration of coagulants to induce hemostasis. Theactivity of zeolite materials leads to an exothermic reaction in wound bed, which has been addressed by embeddingzeolite in a surgical mesh so it can be used as a compressto absorb water less exothermically by using ion exchangetechnique and prehydration [92,93]. Zeolite materials areinexpensive, stable, easy-to-use, and have shown to haveboth hemostatic and antibacterial properties [89]. In a clinical study, QuikClot was found to control bleeding in 92% ofthe 103 documented cases with 100% of the cases performedby first responders [94].Hemostatic materials can be formed by combining oneor two coagulation cascades or hemostatic proteins including thrombin [95], collagen [96], chitosan [97,98], and fibrin[4,99] as well as non-protein materials such as oxidizedcellulose [96,100] and PEG [100]. These hemostats havebeen used in various forms for surgical applications includingmatrix [96,101], patch [102,103] or liquid [95,99]. The majorchallenges associated with the clinical use of these hemostatic materials include their high cost and non-effectivebleeding control [104].To address these challenges, micro and nanoparticleshave been used as hemostatic agents to control blood loss.For example, in a recent study, cationic hydrogel particles based on N-(3-a-aminopropyl)methacrylamide (APM)were synthesized via inverse suspension polymerization andused as hemostatic agents (Figure 1A) [105]. In vitro studies confirmed the formation of blood aggregation, whichwas due to the high swelling ratio of the hydrogel particles (>1000%) as well as their high positive charge. Thecapability of the engineered particles for rapid hemostasisin vivo was also demonstrated by using a tail amputation ratmodel (Figure 1B and C) and an ovine liver laceration model(Figure 1D and E) [105].Some research groups have focused on developing hemostatic materials based on functionalized nanoparticlescapable of aggregating platelets from blood flow [106—109].For example, Ravikumar et al. created hemostatic nanomaterials through the surface functionalization of liposomeswith 150 nm diameters with three peptides including vonWillebrand factor (vWF)-binding peptide (VBP), collagenbinding peptide (CBP) and cyclic-Arg—Gly—Asp (cRGD)peptide [107]. It was shown that liposomes containingVBP and CBP could facilitate platelet-mimetic adhesionand cRGD functionalized liposomes enhanced the aggregation of platelets onto themselves. Therefore, combinationof all three peptides provided a dual hemostatic function of aggregation and adhesion [107]. In another study,Bertram et al. engineered functionalized nanoparticleswith the capabilities for binding to active platelets toenhance their aggregation rate and consequently stopbleeding [106]. A single emulsion evaporation technique was used to synthesize nanoparticles with thediameter of 170 nm consisted of poly(lactic-co-glycolicacid)-poly-L-lysine (PLGA-PLL) copolymer conjugated withRGD functionalized PEG (Figure 2 A and B). The interaction of engineered nanoparticles with active platelets wasassessed in vitro by using a platelet adhesion and aggregation assay. These synthetic hemostatic nanoparticles alsoreduced bleeding after intravenous injection in an injuredsite in a rat artery by distributing throughout the clot(Figure 2C—E). It was also shown that the nanoparticles wereeffectively cleared within 24 h after infusion, demonstrating