KR20150136360A - Vascular Patch And Preparation Method Thereof - Google Patents

Abstract

The present invention relates to a vascular patch for repairing blood vessels, and more specifically, to a vascular patch preventing blood from leaking out while a blood wall is being regenerated by being precisely attached on an affected area of a damaged blood vessel. The vascular patch of the present invention also protects the damaged blood vessel from external environment so as to prevent the interruption of regeneration. Furthermore, the vascular patch minimizes the reduction in blood circulation and an inner radius of the blood vessel while inducing the regeneration of new blood walls on the affected area in the blood vessel.

Description

Technical Field [0001] The present invention relates to a vascular patch,

The present invention relates to a blood vessel patch for repairing damaged blood vessels.

Vascular injury during surgery in the oral and maxillofacial surgery can occur during surgical removal of the neck if the neck is removed or reconstructed, the maxillofacial trauma, or the lesion is adjacent to the main vessel. In the case of vascular injury, a method of ligation of damaged blood vessels or direct closure of injured sites is being used. However, in the case of large vessels such as carotid arteries, which are commonly encountered during neck cleansing, various complications such as cerebral infarction are reported to occur at a high frequency during ligation. In addition, in the case of direct suturing of severe damage due to vascular wall defect, the diameter of the blood vessel becomes narrow, which may result in cerebral infarction due to vascular occlusion or neurological complications due to deterioration of blood vessel function. Therefore, there is a clinical need to develop a simple treatment method and materials for maintaining damaged vessels more functional and regenerating injured parts.

Vascular patches are used for cardiovascular vascular injury to reduce complications such as vascular occlusion due to reduction of vessel diameter by direct suture. There have been many reports comparing the treatment of vascular injury with direct suture and the treatment of vascular injury using vascular patch, and it has been reported that vascular patch treatment shows better results. However, the existing products are expensive and have a limited application to relatively thin blood vessels in the oral and maxillofacial region, which are manufactured in accordance with the cardiovascular system. Therefore, the development of clinical materials which are more economical and which are suitable for thinner blood vessels in the oral maxillofacial region is required.

Silk is known as a biocompatible material and has been in clinical use for decades as a surgical sealant. In addition, since silk has less foreign body reaction to living tissue and its mechanical and physical properties are excellent, various attempts have been made recently for clinical use.

Recently, artificial eosinophils have been developed and applied to clinical practice, and many studies are being conducted on the usefulness as shielding membranes for inducing bone regeneration in bone defect sites.

Further, a process for producing a three-dimensional silk nanofiber membrane for artificial dermis substitution by electrospinning a silk protein or silk protein complex obtained from silkworm cocoons or silk fiber with a technique relating to an artificial dermis using a silk protein and a method of producing the same is disclosed (Korea Patent Publication No. 2013-0051602).

However, there is a problem that the above processes are difficult to apply to thin blood vessels. Therefore, development of a blood vessel patch that can act as a shielding membrane for regenerating a new blood vessel wall by growing vascular endothelial cells as a vascular defect site is required.

Korean Patent Publication No. 2013-0051602.

An object of the present invention is to provide a blood vessel patch for regenerating a new blood vessel wall with a defective portion of a damaged blood vessel and a method of manufacturing the same.

In order to achieve the above object,

The present invention relates to biodegradable fibers; And a blood-clotting component contained in the biodegradable fiber.

The present invention also provides a method for preparing a blood vessel patch comprising infiltrating a biodegradable fiber with an antithrombotic component using an infiltration method.

Since the blood vessel patch according to the present invention includes biodegradable fibers, it does not require a separate removal process after suturing of a vascular defect, plays a role of regenerating a new blood vessel wall while biodegrading into a damaged blood vessel region, , Minimizes blood clotting and thrombus formation during vascular suturing, and is less expensive and simpler than conventional vascular restoration materials.

1 is an image showing a scanning electron microscope (SEM) photograph of the surface of a blood vessel patch according to the present invention.
FIG. 2 is a photograph showing a state in which a blood vessel defect is sutured by a blood vessel patch according to the present invention.
3 is an image showing a scanning electron microscope (SEM) photograph of the surface of a Gore-Tex vascular patch, which is a comparative example of the present invention.
FIG. 4 is a photograph showing a state in which a vascular defect is sutured by a Gore-Tex vascular patch of a comparative example.
Fig. 5 is a photograph showing a state in which a blood vessel defect is sutured by direct suture, which is another comparative example.
FIG. 6 is a graph comparing peak systolic velocity (PSV) values of a blood vessel after 1 week of suture of a vascular defect.
FIG. 7 is a graph comparing peak systolic velocity (PSV) values of blood vessels 3 weeks after the suture of a vascular defect.
FIG. 8 is a photograph of a wire placed on the distal end of a blood vessel defect portion in order to know the position of the blood vessel defect portion in the angiogram and the ultrasonic test.
FIG. 9 is a photograph of an angiogram taken three weeks after restoration of a blood vessel defect with a blood vessel patch according to the present invention. FIG.
FIG. 10 is a photograph of an angiogram taken three weeks after restoration of a vascular defect with a Gore-Tex vascular patch of a comparative example.
FIG. 11 is a photograph of a blood vessel defect portion sealed with a direct suture as another comparative example and taken by angiography 21 days later.
FIG. 12 is an image of a section of a tissue after 2 weeks after repairing a vessel defect with a blood vessel patch according to the present invention.
FIG. 13 is an image of a cross-section of a tissue after 2 weeks of restoration of a vascular defect with a Gore-Tex vascular patch of a comparative example.
FIG. 14 is an image of a cross section of a tissue after 2 weeks from suturing a vessel defect with a direct suture, which is another comparative example.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail.

It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

In the present invention, the terms "comprising" or "having ", and the like, specify that the presence of a feature, a number, a step, an operation, an element, a component, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

Hereinafter, the present invention will be described in detail with reference to the drawings, and the same or corresponding components are denoted by the same reference numerals regardless of the reference numerals, and a duplicate description thereof will be omitted.

Hereinafter, a blood vessel patch according to the present invention will be described in detail.

The present invention relates to biodegradable fibers; And a blood-clotting component contained in the biodegradable fiber.

Biodegradable fiber is a fiber that is degraded by an enzyme secreted by a microorganism existing in nature. When applied to a living body, the biodegradable fiber scarcely causes an inflammation reaction and has a property of being decomposed in vivo. In addition, the anti-thrombogenic component is a component that inhibits the coagulation of blood, and has a property of inhibiting the inflammation and minimizing thrombosis when applied to blood vessels of a living body.

Therefore, the blood vessel patch according to the present invention contains the biodegradable fiber and the anti-thrombotic component, thereby suppressing the inhibition of the inflammatory reaction and minimizing thrombogenesis.

In one embodiment of the present invention, the blood vessel patch may have a degree of biodegradation of 50% or more at 4 weeks after transplantation into the external carotid artery of the white paper. Specifically, the degree of biodegradation may be 50 to 95%, more specifically 50 to 75%. When the biodegradability of the patch for a blood vessel according to the present invention is within the above range, there is an advantage that a separate removal step after the vascular sealing is not necessary. In addition, it is possible to prevent the blood vessel patch from being decomposed before the blood vessel is sufficiently generated. Therefore, the blood vessel patch according to the present invention is effectively biodegraded in the blood vessel defect part over time and can be easily used for regeneration of blood vessel wall and recovery of blood flow volume.

In one embodiment of the present invention, the blood vessel patch may satisfy Equation (1) below.

[Equation 1]

In Equation (1)

V ₁ represents the maximum contraction rate (cm / s) of the blood vessel at 1 week after transplantation of the external carotid artery,

V ₂ is the maximum rate of contraction of the vessel (cm / s) at 3 weeks after transplantation of the patch into the external carotid artery of the rats.

The numerical value in the equation (1) is the rate of change of the maximum contracting velocity of the blood vessel after transplanting the blood vessel patch. The blood vessel patch of the present invention has a rate of change of the maximum contraction rate (cm / s) of blood vessels of 20% or less after implantation in the external carotid artery of the white paper. Specifically, the reduction rate is 1% to 20%, 1% to 8% To 18%. ≪ / RTI >

It was confirmed that the blood vessel patch of the present invention had excellent biodegradability and at the same time, the rate of change of the maximum contracting velocity of the blood vessel was relatively stably maintained.

In one embodiment of the present invention, the biodegradable fibers can be used without limitations as long as they are biodegradable in vivo. For example, the biodegradable fibers can be made of silk.

Silk is a biocompatible material, has little foreign body reaction to living tissue and is excellent in mechanical and physical properties. In addition, silk is thin and easy to operate, which is suitable for application to thin blood vessels and has an advantage that it is not torn easily even in a wet state.

The silk is characterized in that it is derived from the endothelial component of the cocoon.

Silk fibroin, an endothelium component of cocoon, is a typical natural polymer substance. It has excellent cell adhesion ability and proliferative effect while hardly causing an inflammation reaction when applied to a living body. Therefore, silk fibroin is excellent in biocompatibility and can be formed into various forms such as powders, membranes, porous bodies and gels without a rejection reaction to the human body even without special purification process.

Therefore, when the blood vessel patch according to the present invention is applied to a blood vessel defect portion, a new blood vessel wall is regenerated by growing endothelial cells without inflammation or foreign body reaction, and a shielding film which blocks regeneration from the external environment while the blood vessel wall is regenerated And it is possible to improve the biodegradability of the silk and the regeneration effect of the vascular defect, thereby effectively healing the blood vessel.

In one embodiment according to the present invention, the anti-thrombogenic component may be used without limitation as long as it is commercially available, for example, the anti-thrombotic component may be 4-hexylresorcinol . 4-Hexylresorcinol is a natural phenolic compound, known as a component of food additives or bacteriostats to prevent browning of food. When such 4-hexyl resorcinol is applied to the blood vessels of human body, it shows an effect of reducing the production of blood clots.

Accordingly, the blood vessel patch according to the present invention minimizes the inhibition of the inflammatory reaction, the thrombus formation, and the reduction of the inner diameter of the blood vessel during suture of the vascular defect.

In another embodiment of the present invention, the content of the thrombogenic component may be 0.1 to 10 parts by weight based on 100 parts by weight of the biodegradable fiber. Specifically, the content of the anti-thrombogenic component may be 0.01 to 20 parts by weight, or 0.01 to 0.5 parts by weight, or 9 to 20 parts by weight, or 0.1 to 10 parts by weight, or 0.05 to 5 parts by weight . When the thrombogenic component is used in the above-mentioned weight range with respect to 100 parts by weight of the biodegradable fiber, thrombosis of the blood vessel defect site can be minimized and the regeneration effect of the blood vessel defect site can be improved. Therefore, the inner diameter of the blood vessel is prevented from being narrowed, and the amount of perfusion of the blood flow can be restored normally.

In another embodiment of the present invention, the thickness of the vascular patch may range from 0.01 to 1.0 mm, and more specifically from 0.05 to 0.5. When the thickness of the patch for a blood vessel according to the present invention is in the above range, it can be easily used for healing a defective portion of a thin blood vessel such as the oral maxillofacial region of the human body. In addition, it is possible to minimize the phenomenon that the inner diameter of the blood vessel is reduced as the damaged vessel wall is regenerated.

Therefore, the blood vessel patch according to the present invention may be suitable for application to a thin blood vessel, and may be easily used, for example, for vascular injury treatment used in the oral and maxillofacial region of the human body.

The anti-thrombogenic component of the present invention may be, for example, a component for preventing, alleviating or treating vascular diseases. The anti-thrombogenic component according to the present invention is effective in preventing thrombus formation, inhibiting vasoconstriction, and / or inhibiting cholesterol. Specifically, the anti-thrombogenic component may be for improving blood circulation due to antithrombotic effect, and may be a pharmaceutical composition effective for alleviation or treatment of vascular diseases including obesity, diabetes and hyperlipemia. Such vascular diseases include, for example, obesity, diabetes, stroke, cerebral hemorrhage, arteriosclerosis, angina pectoris, myocardial infarction, hypertension, anemia, migraine or hyperlipidemia.

The anti-thrombogenic component of the present invention can be easily formulated according to the conventional method. Surfactants, excipients, coloring agents, spices, preservatives, stabilizers, buffers, suspending agents and other adjuvants can be suitably used.

The patch for a blood vessel according to the present invention may contain other components or the like which can give a synergistic effect to the main effect within a range not impairing the intended main effect of the present invention. For example, additives such as perfume, coloring agent, bactericide, antioxidant, preservative, moisturizing agent, thickening agent, inorganic salt, emulsifier and synthetic polymer substance may be further added for improvement of physical properties. In addition, it may further contain auxiliary components such as water-soluble vitamins, oil-soluble vitamins, polymer peptides, polymeric polysaccharides and seaweed extract. The above components may be mixed and selected without difficulty by those skilled in the art depending on the purpose of formulation or use, and the amount thereof may be selected within a range that does not impair the objects and effects of the present invention. For example, the addition amount of the components may be in the range of 0.01-5 wt%, more specifically 0.01-3 wt%, based on the total weight of the anti-thrombogenic component.

Hereinafter, a method for manufacturing a blood vessel patch according to the present invention will be described in detail.

The method for manufacturing a blood vessel patch according to the present invention may include a step of infiltrating the biodegradable fiber with the antithrombotic component by using an infiltration method.

In the method for manufacturing a blood vessel patch, the biodegradable fiber can be used without limitation as long as it is a biodegradable fiber. For example, the biodegradable fiber may be a silk.

In the method for manufacturing a blood vessel patch according to the present invention, the silk is an endothelium of dried cocoon.

Specifically, in the method for manufacturing a blood vessel patch according to the present invention, the silk may include a step of disinfecting and washing the cocoon, and drying the cocoon to physically peel off the portion corresponding to the endothelium.

Fibroin, the endothelium component of cocoon, has excellent biocompatibility because it has excellent adhesion ability and proliferative effect, while causing little inflammatory reaction when applied to living body. In addition, there is little rejection to the human body without special purification process, and it can be manufactured in various forms such as powder, membrane, porous body and gel.

Therefore, the vascular patch of the present invention contains the endothelial component of the cocoon, thereby improving the biodegradability in the blood vessel and the regeneration effect of the blood vessel defect portion.

The anti-thrombogenic component may be used without limitation as long as it is commercially available. For example, the anti-thrombotic component may be 4-hexyl resorcinol.

In the method for manufacturing a blood vessel patch according to the present invention, the method of infiltration may include a method of immersing a biodegradable fiber in a solution containing a thrombosection component for a predetermined period of time to infiltrate the solution into the fiber.

For example, in the method for manufacturing a blood vessel patch, the step of infiltrating 4-hexyl resorcinol into the silk using the infiltration method comprises: putting the prepared silk into the 4-hexyl resorcinol solution, To < RTI ID = 0.0 > 30 hours. ≪ / RTI > Specifically, the infiltration treatment time can be treated for 15 to 27 hours.

Specifically, the 4-hexyl resorcinol may be dissolved in an alcohol to prepare a 0.5 to 10% solution. Specifically, the solution can be used in a concentration range of 1 to 5% (v / v).

When the infusion method is performed by adding 4-hexylresorcinol in an amount within the above range, it is possible to maximize the vascular regeneration effect and the thrombogenic effect of the blood vessel patch.

Hereinafter, the present invention will be described in more detail with reference to Examples and Experimental Examples.

However, the following Examples and Experimental Examples are merely illustrative of the present invention, and the present invention is not limited to the following Examples and Experimental Examples.

Example : silk  Suture of vessel defect with vascular patch

One. Silk  Manufacture of Vessel Patch Used

The cocoon was sterilized and washed, then cut and dried. Silk was obtained by physically peeling the part corresponding to the endothelium from the dried cocoon. After that, 4-hexyl resorcinol was dissolved in alcohol to make a 3% 4-hexyl resorcinol solution. 10 g of the silk fiber obtained from the silkworm cocoa was placed in a 3% 4-hexylresorcinol solution and infiltrated for 24 hours in order to infiltrate the silk extracted and peeled from the silkworm cocoon. Through the invasion method, the silk permeated with 4-hexyl resorcinol was placed in a 45 ° C drying oven to evaporate all of the alcohol. The weight of the silk after drying was 10.3 g. Silk evaporated with alcohol was sterilized by ethylene oxide sterilization (EO gas) to prepare a blood vessel patch.

FIG. 1 shows an image of a scanning electron microscope (SEM) photograph of the surface of a blood vessel patch according to the present invention manufactured by the above process.

2. Vascular defect suture

The vascular defect was sutured using the silk vascular patch manufactured by the above manufacturing method. Seven rats were used as experimental animals. First, all the hairs on the right carotid artery of the white paper were removed and the skin was disinfected. A 0.5 × 1 mm vascular defect was formed in the exposed right carotid artery using a microscissor. The formed defect was reconstructed using the prepared blood vessel patch, and the patch for the silk blood vessel was fixed with 10-0 monofilament nylon (10-0 monofilament nylon, Ailee, Korea).

FIG. 2 is a view for sealing a blood vessel defect with a patch for a silk blood vessel according to the present invention.

Comparative Example 1 : Gore-Tex Gore - Tex ) Vascular patches  Suture

(Gore & Associates, Inc, USA), which was previously imported through Gore Korea and used for cardiovascular surgery, was prepared.

3 is an image showing a scanning electron microscope (SEM) photograph of the surface of a Gore-Tex vascular patch, which is a comparative example of the present invention.

Seven rats were used as experimental animals. First, all the hairs on the right carotid artery of the white paper were removed and the skin was disinfected. A 0.5 × 1 mm vascular defect was formed in the exposed right carotid artery using a microscissor. The defect was reconstructed using a Gore-Tex vascular patch and the Gore-Tex vascular patch was fixed with 10-0 monofilament nylon (10-0 monofilament nylon, Ailee, Korea).

Figure 4 A photograph of a vessel in which a vessel defect is sutured by the Gore-Tex blood vessel patch

Comparative Example 2 : Suture of vessel defect by direct suture

Seven rats were used as experimental animals. First, all the hairs on the right carotid artery of the white paper were removed and the skin was disinfected. A 0.5 × 1 mm vascular defect was formed in the exposed right carotid artery using a microscissor. The defects were directly sutured using 10-0 monofilament nylon (10-0 monofilament nylon, Ailee, Korea).

FIG. 5 is a photograph showing a state in which a blood vessel defect is sutured through direct suturing.

Experimental Example  1: Ultrasonic analysis and histological analysis

Ultrasonic analysis

Ultrasonography was performed to confirm the hemostasis and stenosis of the sutured vascular defect. Peak Systolic Velocity (PSV) was measured with ultrasound to determine whether the vessel was functionally regenerated.

FIG. 6 is a graph comparing the maximum contraction rate values after 1 week after suturing of a vascular defect. Referring to FIG. 6, the maximum contraction rate measured at 1 week after vessel suture closure was 41.20. + -. 7.92 cm / s in the example of the present invention, 32.74 + 10.50 cm / s and 75.23 ± 27.05 cm / s in the case of the direct sutured Comparative Example 2. Analysis of variance (ANOVA) showed statistically significant difference between the three groups (p = 0.007).

FIG. 7 is a graph comparing the maximum contraction rate values after three weeks after suturing of a vascular defect. Referring to FIG. 7, the maximum contraction rate measured at 3 weeks after vessel suture closure was 35.92 +/- 1.45 cm / s in the example of the present invention and 35.36 +/- 1.45 cm / s in Comparative Example 1 using Gore- 7.27 cm / s, and 48.36 ± 6.15 cm / s in Comparative Example 2 which was directly sealed. Analysis of variance (ANOVA) showed statistically significant difference between the three groups (p = 0.029).

Histological analysis

Histological analysis was performed to confirm the thickness of the vessel wall and the diameter of the blood vessel in the sutured vessel defect area and confirm the foreign body reaction by the vascular patch. In order to maintain the diameter of the blood vessel, both sides of the blood vessel were ligated, and both blood vessels were cut with the blood kept in the blood vessel to obtain a specimen. The obtained sample was fixed with alcohol. Hematoxylin and eosin were used to stain the specimens. Fixed and stained blood vessel specimens were observed by cross-sectioning.

12 is an image of a section of a tissue after two weeks of passage of a blood vessel sealed with a blood vessel patch according to the present invention. Fig. 13 is an image of a section of blood vessel tissue after 2 weeks of lapse of Comparative Example 1; Fig. 14 is an image of a section of a blood vessel tissue after 2 weeks of lapse of Comparative Example 2. Fig.

Histopathological findings showed that no foreign body reaction was observed around the patch for blood vessels of the present invention. In addition, the reconstructed vessel wall was not particularly distinguished from the surrounding tissues and the internal diameter of the blood vessel was maintained well. Comparative Example 1 using the Gore-Tex vascular patch also showed a good preservation of the vascular internal diameter, but showed overgrowth of the vascular lining in some specimens. In contrast, Comparative Example 2, which was directly sutured, showed a much narrower blood vessel diameter.

Therefore, the blood vessel patch according to the present invention significantly reduces the overgrowth of the blood vessel wall and the narrowing of the blood vessel inner diameter compared to the conventional Gore-Tex blood vessel patch and direct suture method, And it was confirmed that it can effectively function to maintain.

Experimental Example  2: The angiographic diameter  Change analysis

Angiography was performed to determine the function and diameter of the vascular defect in the sutured vascular defect. Angiography was performed after 2 weeks of suture closure.

Intravenous injection (IV) was performed with 21 Gauze canula, 3 mg VISPAQUE® was injected slowly, and bilateral carotid arteries were simultaneously injected. At this time, the wire was positioned at the distal end of the vessel defect site to know the position of the vessel defect site.

FIG. 8 is a view showing a wire positioned at the distal portion of the blood vessel defect portion in order to know the position of the blood vessel defect portion in the angiogram and ultrasound examination.

The results are shown in Figures 9-11. The sutured vascular defect is indicated by a white arrow, and the white substance taken up and down of the vascular defect is the wire positioned to locate the vascular defect.

FIG. 9 shows the result of the imaging of the embodiment according to the present invention. Fig. 10 shows the result of the imaging of Comparative Example 1. Fig. Fig. 11 shows an angiographic photograph of Comparative Example 2. Fig. 9 to 11, it can be seen that the diameter of the blood vessel is maintained in a good condition in the case of FIG. 9 in which the silk vascular patch of the present invention is sewn.

Claims (10)

Biodegradable fibers; And a thrombogenic component contained in the biodegradable fiber.
The method according to claim 1,
Wherein the patch for blood vessels has a biodegradability of 50% or more at 4 weeks after transplantation into the external carotid artery of the white paper.
The method according to claim 1,
Wherein the blood vessel patch satisfies the following expression (1): " (1) "
[Equation 1]

In Equation (1)
V ₁ represents the maximum contraction rate (cm / s) of the blood vessel at 1 week after transplantation of the external carotid artery,
V ₂ is the maximum rate of contraction of the vessel (cm / s) at 3 weeks after transplantation of the patch into the external carotid artery of the rats.
The method according to claim 1,
Wherein the biodegradable fiber comprises silk.
5. The method of claim 4,
Wherein the silk is derived from the endothelial component of the cocoon.
The method according to claim 1,
The anti-thrombotic component comprises a 4-hexylresorcinol patch.
The method according to claim 1,
Wherein the content of the anti-thrombogenic agent is 0.1 to 10 parts by weight based on 100 parts by weight of the biodegradable fiber.
The method according to claim 1,
The thickness of the patch for blood vessels is 0.01 to 1.0 mm.
A method for manufacturing a blood vessel patch comprising the step of infiltrating a biodegradable fiber with an antithrombotic component by using an infiltration method.
10. The method of claim 9,
Wherein the biodegradable fiber is an endothelium of dried cocoon.

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