Patent Application
20220241152
This application relates in general to medicine, and in particular, to a fibrin biopolymer formation and application device.
Biopolymers are polymers that are composed of naturally-occurring substances, such as amino acids, sugars, lipids, and nucleic acids. While many biopolymers are produced naturally in living organisms, they can also be synthesized outside of living organisms, and depending on their properties and ease of synthesis, have been shown to have potential in many areas of medicine, including damaged tissue treatment, drug delivery, and gene therapy.
One particularly promising class of biopolymers are fibrin biopolymers that are the most abundant component of blood clots. Naturally, fibrin biopolymers are formed from fibrinogen molecules (with fibrinogen being a glycoprotein that circulates in the blood of all invertebrates) being enzymatically processed by thrombin or thrombin-related enzymes upon the organism sustaining a vascular injury that requires clotting. Despite the promise of exogenous fibrin biopolymers for wound treatment, their application remains largely limited to clinical settings and out of reach of every day consumers that buy medical products over the counter. An example of such limitation is seen in International Application Publication No. WO2015172215, published Nov. 19, 2015, entitled “Fibrin Sealant For Topical Use, Method For Producing Same and Use Thereof,” by Rui Seabra Ferreira Junior, Benedito Barravieira, and Silvia Regina Sartori Barravieira (“the Ferreira publication”), the disclosure of which is incorporated by reference. The Ferreira publication discloses combining fibrinogen of animal origin with a thrombin-like serinoprotease (known as gyroxine) purified from venom of a snake Crotalus durissus terrificus in the presence of calcium chloride, with the serinoprotease cleaving the fibrinogen molecules into fibrin monomers. The fibrin monomers polymerize in the presence of calcium into a fibrin biopolymer, which has sealing and adhesive properties, and can be used in wound care. The Ferreira publication states that the three components necessary to create the fibrin biopolymer (the fibrinogen, the serinoprotease, and a diluent that includes calcium chloride) are kept in separate vials at −20° C. prior to being combined using multiple syringes and topically applied to a skin wound. The requirement for −20° C. storage and the use of multiple syringes for creation and application of the fibrin biopolymer makes this technology useful only within a hospital or a doctor's office setting, preventing the technology's application for treatment of every day skin wounds.
Attempts have been made to make the fibrin biopolymer technology more accessible to non-medical personnel, but such attempts have turned up deficient. For example, International Patent Application Publication No. WO2018191800, entitled “Device For Applying Fibrin Biopolymers,” published on Oct. 25, 2018, by Moacyr Ramos Bighetti and Ana Silvia Sartori Barraviera Seabra Ferreira, the disclosure of which is incorporated by reference, discloses an adhesive bandage whose support structure is impregnated with powdered serinoprotease purified from snake venom and a fibrinogen-rich cryoprecipitate extracted from large animals. The bandage further includes a compartment positioned above the support structure that includes a diluent liquid, which when released onto the support structure causes a formation of a sealant and transparent film on the bandage that can be applied to a wound. The application of such a bandage is limited by the size and shape of the bandage, thus being able to cover only small wounds of a particular shape. Further, if such a bandage is applied to a wound larger than the area of the bandage, the adhesive portions of the bandage would come into contact with the wound surface and damage the wound surface when removed, thus aggravating the wound and interfering with the healing process. Finally, as such the fibrin biopolymer tends to solidify within seconds of the mixing of necessary components, if a user fails to place the bandage onto a correct spot within those seconds, the bandage becomes useless.
Finally, International Patent Application Publication No. WO2018191801, entitled “Method for Producing A Fibrin Biopolymer, Means For Applying Said Fibrin Biopolymer and Method For Applying Said Fibrin,” published Oct. 25, 2018, by Moacyr Ramos Bighetti and Ana Silvia Sartori Barraviera Seabra Ferreira (“the Bighetti publication”), the disclosure of which is incorporated by reference, discloses a spray bottle that has three compartments, with one compartment storing a powdered fibrinogen-rich cryoprecipitate extracted from large animals, another compartment storing a serinoprotease supplied from snake venom, and the third compartment storing a liquid diluent. Each compartment includes an inert gas under a high pressure, which acts as a propellant to drive the contents of each compartment through a spray nozzle. The Bigghetti publication states that the expelled contents of the compartments mix with each other in the air on their path to the wound to be treated and on the wound to form a biopolymer. However, unless the spray bottle is used at a particularly short distance (which would allow to cover only a small patch of a patient's skin with the fibrin biopolymer), the powdered compartments expelled from the bottle would start dispersing from the path on which the mixing would occur, thus both reducing the amount of fibrinogen and serinoprotease available for forming the fibrin polymer and resulting in the landing of the powders on an undesired surface, where the unreacted powders can be broken down as nutrients for bacteria and other pathogens. Further, the diluent (with the powdered components mixed in), can splatter, and in addition to gravity influencing the direction at which the diluent moves before polymerization is complete, leads to difficulty in controlling the shape of the resulting fibrin biopolymer film that results from the application of the spray.
Accordingly, there is a need for a device that allows to easily control an application of a fibrin biopolymer to a wound surface without wasting biopolymer components and that can be used in both medical personnel and as an over-the-counter product.
The two devices described below allow for greater control over application of a fibrin biopolymer and yet remain simple enough to be used by both medical personnel and by non-medical workers who buy the devices over the counter. One of the devices includes chambers where components necessary for formation of a fibrin biopolymer are stored and are pushed by plungers connected to an actuator upon the actuator receiving pressure from the user, with the components mixing in a chamber within the device and flowing out of a tube connected to the mixing chamber before formation of the fibrin biopolymer is completed. The other device dispenses formulations that include components necessary for formations of a fibrin biopolymer onto a skin of a patient using one or more propellants, with the formation of the fibrin biopolymer being initiated after the formulations are dispensed on the patient's skin and are intentionally mixed together by a patient or a person providing care to the patient. The formulations are more viscous than water, and thus are not easily moved from their positions before they are intentionally mixed together, providing control over the start of the formation of the fibrin biopolymer that is necessary when the biopolymer needs to be applied to a large portion of the patient's skin. Further, both devices allow to reduce the waste of components present in earlier works.
In one embodiment, a fibrin biopolymer formation and application device is provided. The device includes a housing and a plurality of compartments formed within the housing, the plurality of compartments including: a fibrinogen compartment whose contents include fibrinogen; a serinoprotease compartment whose contents comprise a serinoprotease, wherein the serinoprotease cleaves the fibrinogen into fibrin monomers when combined with the fibrinogen; and a diluent compartment whose contents comprise a diluent, the diluent comprising a cofactor, wherein the fibrin monomers polymerize into a fibrin polymer in the presence of the cofactor. The device further includes the mixing chamber formed adjacent to the compartments, the mixing chamber including an opening; a tube positioned at one end of the housing and interfaced to the opening in the mixing chamber; and an actuator positioned at another end of the housing and connected to a plurality of plungers, wherein a pressure applied on the actuator drives the plungers to push at least a portion of the contents of all of the compartments into the mixing chamber to form a mixture in which the serinoprotease cleaves the fibrinogen into the fibrin monomers and the polymerization begins and wherein at least a portion of the mixture flows out via the opening into the tube and flows out from a distal end of the tube prior to a completion of the polymerization of the fibrin monomers in the at least the portion of the mixture into the fibrin biopolymer.
In a further embodiment, a device for fibrin-biopolymer-forming substance application is provided. The device includes a housing and a plurality of compartments formed within the housing, contents of each of the compartments including one or more propellants, the plurality of the compartments including: a fibrinogen compartment whose contents further include a formulation more viscous than water and comprising fibrinogen; a serinoprotease compartment whose contents further include a further formulation more viscous than water and comprising a serinoprotease, wherein the serinoprotease cleaves the fibrinogen into fibrin monomers when combined with the fibrinogen; and a cofactor compartment whose contents include an additional formulation more viscous than water and include a cofactor, wherein the fibrin monomers polymerize into a fibrin biopolymer in the presence of the cofactor. The device further includes a plurality of valves, each of the valves integrated into one of the compartments and adapted to take a closed position and an open position; a plurality of at least partially hollow conduits, each of the conduits including a first end that is at least partially interfaced to one of the valves, the first end including a first opening, each of the conduits further including a second end including a second opening that is interfaced to one of a plurality of orifices within an actuator; the actuator interfaced to all of the conduits and configured to apply pressure to all of the valves via the conduits upon being pressed by a user, wherein the pressure shifts the valves from the closed position into the open position and exposes the first opening of each of the conduits to the contents of the compartments, and wherein at least part of the contents of each of the compartments is propelled by the one or more propellants via the first openings of the conduits to flow via the conduits out of the second openings and out of the orifices of the actuator while the valves remain in the open position, and wherein the fibrinogen formulation, the serinoprotease formulation, and the cofactor formulation form the fibrin biopolymer when mixed outside of the actuator.
Still other embodiments will become readily apparent to those skilled in the art from the following detailed description, wherein are described embodiments by way of illustrating the best mode contemplated. As will be realized, other and different embodiments are possible and the embodiments' several details are capable of modifications in various obvious respects, all without departing from their spirit and the scope. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not as restrictive.
Improved control over where how and where a fibrin biopolymer is applied to wounds can be provided via two devices is described below. When applied, the fibrin polymer accelerates the rate that wounds are healed, reduces possibilities of infections, and protects the wounded area from further external impacts. Due to being simple to use, the devices described below can be sold over the counter as well used by trained medical personnel. Further, at least some embodiments of the devices can be stored at room temperature for long enough to be of practical use without significant potency degradation, further contributing to practicability of the devices.
A button 12 is inserted into an opening on an end of the housing 13 opposite to the end to which the tube 14 is attached. The portion of the button 12 outside the housing 13 is substantially cylindrical, though in a further embodiment, other shapes are possible. Additionally, the button 12 can include appendages (not shown) attached to the cylindrical portion to increase the ease of handling of the button and prevent the button 12 from falling through the opening of the housing 13 into which the plunger is inserted. In a further embodiment, other shapes of the button 12 are possible. In a still further embodiment, external actuators other than the button 12 could be used to trigger the formation and application of the biopolymer described below. In a still further embodiment, a removable protective cap (not shown) could be placed on top of the button to prevent an accidental pressing of the button 12.
Internally, the housing 13 includes compartments where components necessary for formation of a fibrin biopolymer are stored.
Attached to the base 30 are a plurality of plungers 15 that rest on a seal 16 (such as a thin plastic film) separating the plungers from the compartments where components necessary to create the fibrin biopolymer are stored. In one embodiment, there are four plungers 15 attached to the base 30, as can be seen with reference to
As shown with reference to
The contents of the compartments 21, 23, 25, 27 are described below.
The compartment 21 (referred to as the fibrinogen compartment below) stores a powder 22 that includes fibrinogen protein molecules. In one embodiment, the powder can be a fibrinogen-rich cryoprecipitate (insoluble, cold-precipitated fraction of frozen fresh plasma). The cryoprecipitate can be extracted from large animals through techniques known in the art, such as from bovine animals (such as buffalos), though other sources of the cryoprecipitate are possible. In one embodiment, the cryoprecipitate can include in addition to the fibrinogen, factor VIII, factor V, and von Willebrand factor (such as in the case of a bubaline cryoprecipitate described in detail by the Ferreira publication cited above and whose disclosure is incorporated by reference). In a further embodiments, other components of the cryoprecipitate are possible. In a further embodiment, the powder 22 can include fibrinogen that was recombinantly produced in bacteria, yeast (or other fungi), mammalian cell culture, or other cell culture, and purified through chromatographic (such as high performance liquid chromatography or fast performance liquid chromatography) and other protein purification techniques known in the art. Once purified to a sufficient degree of purity, the fibrinogen is lyophilized to create the powder. Still other ways to produce the powder 22 that includes the fibrinogen are possible. The recombinantly produced fibrinogen can be a bovine fibrinogen (such as a buffalo fibrinogen), though other kinds of fibrinogen can also be made recombinantly. When a bovine or other non-human fibrinogen is used to make a fibrin biopolymer applied to a human, such fibrin biopolymer is considered heterologous.
The compartment 23 (referred to as the serinoprotease compartment below) stores a powder 24 that includes serinoprotease molecules capable of cleaving the fibrinogen molecules stored in the fibrinogen compartment 21 into monomers necessary for creation of a fibrin biopolymer. Such serinoprotease can be gyroxine extracted from the snake Crotalus durissus terrificus described in detail by the Ferreira publication cited above and whose disclosure is incorporated by reference. Alternatively, the gyroxine can be produced recombinantly in bacteria, yeast (or other fungi), mammalian cell culture, or other cell culture, and purified using chromatographic (such as high performance liquid chromatography or fast performance liquid chromatography) and other protein purification techniques known in the art. Once purified to a sufficient degree of purity, the gyroxine is lyophilized to create the powder. In a further embodiment, the serinoprotease (a gyroxine or a similar serinoprotease) could be derived, either through extraction or through recombinant production (as described above), from venom of other snakes, or other kinds of animals, such as when the serionoprotease is athrombin-like enzyme gyroxin B1.3 of the melon fruit fly Zeugodacus cucurbitae. Still other ways to obtain the serinoprotease are possible.
The compartment 27 (referred to as a diluent compartment below) stores a diluent 28 necessary for the serinoprotease in the powder 24 and the fibrinogen in the powder 24 to mix (upon dissolving in the diluent) and for the serinoprotease molecules to cleave the fibrinogen molecules into the fibrin monomers. Such diluent can be water, though other diluents are also possible. Within the diluent 28 are also dissolved calcium molecules, which are necessary for the fibrin monomers to polymerize into the fibrin biopolymer at a rate useful for practical applications, being a cofactor that catalyzes the polymerization reaction. The calcium molecules can be added to the diluent 28 by dissolving within the diluent 28 calcium chloride, calcium carbonate, or calcium phosphate, though dissolving other calcium-containing molecules is also possible. In a still further embodiment, another cofactor instead of calcium could be dissolved within the diluent 28. In one embodiment, the concentration of the calcium within the diluent is 20 mM to 30 mM, though other concentrations are also possible. The calcium concentration can be chosen based on the purpose of a particular device 10. For example, if a device 10 is for use in the clinical settings and is meant for producing a large amount of the fibrin biopolymer, the polymerization of the components into the fibrin biopolymer needs to be slowed down to allow the mixed components to escape from the tube before the components completely polymerize into the fibrin biopolymer and become solid. In such a case, where a patient can be expected to remain motionless when requested to prevent movement of a not-yet-polymerized mixture, the calcium concentration would be towards the 20 mM concentration or below to slow down the polymerization. On the other hand, where the device 10 is intended to be sold over-the-counter for applying a relatively small amount of the fibrin biopolymer to treat a relatively small wound, a quickly polymerizing mixture would be beneficial to make sure that the fibrin polymer covers the desired area and does not leak to undesired areas due to gravity or patient motion. In such a case, a calcium concentration close to 30 mM (or higher) to quicken the polymerization.
Finally, within the compartment 25 stores a powder 26 that includes molecules of one or more coagents that when integrated into the fibrin biopolymer promote desired objectives, such as wound healing. For example, such coagent can include an antibiotic to prevent bacterial growth under the layer of fibrin biopolymer applied to a patient's skin. Other drugs could also be coagents. For example, one or more a coagent could be an anti-cancer drug, though other kinds of drugs are also possible. Alternatively or in addition to the drug, the coagent can be a lyophilized (or otherwise in powder form) protein. For example, such coagent could be Alternagin-C (ALT-C), an ECD-disintegrin-like protein from Bothrops alternatus snake venom shows antiangiogenic activity at concentrations higher than 100 nM. As angiogenesis, formation of new blood vessels, is crucial for tumor development, adding ALT-C (or another protein from the disintegrin family) as a coagent can be used during anti-cancer treatment, as described below. Other properties of ALT-C (or other disintegrin proteins) could be utilized for other kinds of treatments, such as in wound treatment. Still other kinds of proteins are also possible as a coagent, including proteins from the lectin family, such as the lectin protein from the Aplysia dactylomela which have been shown to have potential applications in anti-cancer and wound healing treatments. Still other coagents are possible. For example, the coagent could include stem cells, with the resulting fibrin biopolymer serving as a scaffold for the stem cells. In a further embodiment, the powder 26 that includes the coagent could be combined with the contents of one or more of the compartments 21, 23, or 27, and thus only three compartments 21, 23, 27 would be present. In a still further embodiment, one or more of the coagents could be added to the compartments 21, 23, 27 and one or more of the other coagents would be present in the compartment 25. For example, an antibiotic (or another antibacterial agent, antifungal agent, or both) could be present in the compartments 21, 23, 27 to prevent bacterial or fungal growth while a protein coagent, such as ALT-C, with or without additional antibiotics, could be present in the compartment 25. In a still further embodiment, the powder 26 could be omitted, resulting in only three compartments being present in the device 10.
In a further embodiment, to protect the serinoprotease or a coagent (such as ALT-C protein) from degradation, the serinoprotease or the coagent could be microencapsulated in liposomes while stored in the respective compartments 23, 25. Liposomes are spherical vesicles having at least one lipid layer that can be created by a disrupting a biological membrane (such as by sonication). The liposomes can continue to encapsulate the serinoprotease, the coagent, or both, until the powders 24, 26, or both are mixed with contents of other compartments (such as the diluent 28 or the powder 22) that would include a substance that would cause a release of the contents of the liposomes (such as a detergent that would not denature the proteins encountered or interfere with the polymerization reaction).
The amounts of the fibrinogen, serinoprotease, the diluent, and the coagent in the compartments 21, 23, 25, 27 depends on how much fibrin biopolymer is necessary to be applied from the device 10. For example, in over-the-counter version sold for treatment of superficial skin damage, such as minor burns and cuts, the amounts of the components necessary to make the fibrin biopolymer could be less than in a version of the device 10 used by medical personnel at trauma centers where extensive skin damage that needs to be covered from a single device 10 can be expected. In one embodiment, once the powders 22 and 24 are dissolved within the diluent 28, the ratio of the concentrations of the powder 24 (the powder including the serinoprotease) to the powder 22 (the powder including the fibrinogen) to the calcium within the diluent 28 is 0.4:1.0:0.6. Other ratios are possible. The concentration of the coagent would depend on the kind of coagent used to create the fibrin biopolymer.
As mentioned above, once the seal 18 is broken, the contents of the compartments 21, 23, 25, and 27 enter a mixing chamber 19 seen with reference to
The opening 20 is aligned and connected with the hollow portion of the tube 14 formed at the end of the housing 13, and thus the polymerizing mixture 36 that forms within the mixing chamber 19 travels (under the force of gravity) through the opening 20 into the tube and escapes the device through the distal end of the tube 14. Thus, a user can precisely apply the polymerizing mixture 35 (which will turn into the fibrin polymer once the polymerization is complete) to a target area by holding the tip of the tube 14 over the target area.
While in the description above, the device 10 has been described as being used for treatment of wounds, the device 10 also has a hemostatic surgical use, with the fibrin biopolymer dispensed using the device 10 being used to stop bleeding during surgery, seal a surgical cut, or other surgical use.
Also, while in the description above, the device 10 is described as applying the polymerizing mixture from a distance, when the tube 14 is a needle, the needle could also be inserted through the skin (or a mucous membrane) to deliver the polymerizing mixture 35 (and consequently the fibrin biopolymer 36) under into the site of the tumor, such as under the skin of the patient or on an internal organ of the patient. For example, if the patient has a cancerous tumor, the needle could be inserted into the skin and the polymerizing mixture could be inserted into the tumor or adjacently to the tumor. Any anti-cancer drugs (or proteins, such as the ALT-C or the lectin protein from Aplysia dactylomela) present as a coagent in the fibrin biopolymer 36 placed under the skin would then slowly be released (through osmosis or another mechanism of action) into the tumor. Such injection allows to avoid providing the anti-cancer medication (which often have high toxicity) via the oral route, thus reducing the overall toxicity of the medication to which the patient is exposed and increasing the portion of the anti-cancer medication that is delivered directly to the tumor. Other coagents could similarly be delivered directly to a desired location through an under-the-skin injection.
As shown with reference to
While the above mechanism allows for near-simultaneous release of all of the contents of all the compartments into the mixing chamber 19, in a further embodiment, a mechanism allowing for dosed release of the contents could be implemented.
The device 10 allows controlled, pinpoint application of the fibrin biopolymer desired locations (over which the tube 14 can be positioned). Sometimes, a wound area can be either too large for treatment using the contents of a single device 10, or distributed widely enough throughout the patient's body that covering all of the wound surface using a single device 10 before polymerization of the fibrin biopolymer is complete may be difficult. A device for applying substances that when mixed form a fibrin biopolymer described below provides additional control over the polymerization by allowing to deposit onto the skin components for creating the fibrin biopolymer in the form of foam or gel and to initiate the polymerization by mixing the components (such as with the user's hand) only when the user is ready.
Internally, the housing 46 includes compartments where components necessary for formation of a fibrin biopolymer are stored and which are released using actuation of a valve-based mechanism.
Each of the formulations 55-58 includes a component to be used for formation of the biopolymer. Thus, formulation 55 stored in the compartment 71 includes fibrinogen molecules. The fibrinogen can come as part of a fibrinogen-rich cryoprecipitate (insoluble, cold-precipitated fraction of frozen fresh plasma). The cryoprecipitate can be extracted from large animals through techniques known in the art, such as from bovine animals (such as buffalos), though other sources of the cryoprecipitate are possible. In one embodiment, the cryoprecipitate can include in addition to the fibrinogen factor VIII, factor V, and von Willebrand factor (such as in the case of a bubaline cryoprecipitate described in detail by the Ferreira publication cited above and whose disclosure is incorporated by reference). In a further embodiments, other components of the cryoprecipitate are possible. In a further embodiment, the fibrinogen in the formulation 55 is recombinantly produced in bacteria, yeast (or other fungi), mammalian cell culture, or other cell culture, and purified through chromatographic (such as high performance liquid chromatography or fast performance liquid chromatography) and other protein purification techniques known in the art. The recombinantly produced fibrinogen can be a bovine fibrinogen (such as from a buffalo fibrinogen), though other kinds of fibrinogen can also be made recombinantly. When a bovine or other non-human fibrinogen is used to make a fibrin biopolymer applied to a human, such fibrin biopolymer is considered heterologous.
The formulation 56 in the compartment 72 includes serinoprotease molecules capable of cleaving the fibrinogen in the formulation 55 into monomers necessary for creation of a fibrin biopolymer. Such serinoprotease can be gyroxine extracted from the snake Crotalus durissus terrificus described in detail by the Ferreira publication cited above and whose disclosure is incorporated by reference. Alternatively, the gyroxine can be produced recombinantly in bacteria, yeast (or other fungi), mammalian cell culture, or other cell culture, and purified using chromatographic (such as high performance liquid chromatography or fast performance liquid chromatography) and other protein purification techniques known in the art. In a further embodiment, the serinoprotease (a gyroxine or a similar serinoprotease) could be derived, either through extraction or through recombinant production (as described above), from other snakes, or other kinds of animals, such when the serionoprotease is a thrombin-like enzyme gyroxin B1.3 of the melon fruit fly Zeugodacus cucurbitae. Still other ways to obtain the serinoprotease are possible.
The formulation 57 in the compartment 73 includes calcium molecules, which are necessary for the fibrin monomers to polymerize into the fibrin biopolymer at a rate useful for practical applications, being a cofactor that catalyzes the polymerization reaction. The calcium molecules can be added to the formulation 73 as part of calcium chloride, calcium carbonate, or calcium phosphate, though dissolving calcium-containing molecules also possible. In a still further embodiment, another cofactor instead of calcium could be part of the formulation. As further described below, the formulations are expelled from the device 40 at an equal rate, and the concentration of calcium in the formulation 57 is such that the concentration of calcium ions within the a mixture formed from all four formulations 55-58 is 20 mM to 30 mM, though other concentrations are also possible. For example, with four formulations 55-58 being expelled from the device 40 at an equal rate, the initial concentration of calcium within the formulation 57 would be between 80 mM and 30 mM. In a further embodiment, if the number of formulations is not four, the concentration of calcium (or another catalyst) within the formulation 57 would be different. Similarly to what is described with respect to device 10, increasing or decreasing the calcium concentration outside of the 20 mM to 30 mM could also be used to control the rate of the polymerization once the formulations 55-58 are mixed.
Finally, the formulation 58 in compartment 74 stores includes one or more coagent molecules that when integrated into the fibrin biopolymer promote desired objectives, such as wound healing. For example, such coagent can include an antibiotic to prevent bacterial growth under the layer of fibrin biopolymer applied to a patient's skin. Other drugs could also be coagents. For example, one or more a coagent could be an anti-cancer drug, though other kinds of drugs are also possible. Alternatively or in addition to the drug, the coagent can be a lyophilized (or otherwise in powder form) protein. For example, such coagent could be Alternagin-C (ALT-C), an ECD-disintegrin-like protein from Bothrops alternatus snake venom shows antiangiogenic activity at concentrations higher than 100 nM. As angiogenesis, formation of new blood vessels, is crucial for tumor development, adding ALT-C (or another protein from the disintegrin family) as a coagent can be used during anti-cancer treatment. Other properties of ALT-C (or other disintegrin proteins) could be utilized for other kinds of treatments, such as in wound treatment. Still other kinds of proteins are also possible as a coagent. Still other coagents are possible. In a further embodiment, the coagent could be added to one or more of the formulations 55-57, and the formulation 58 would be omitted from the device 40. In that case, the compartment 74 would also be omitted from the device 40, and the device 40 would have only have three compartments 71-73. In a still further embodiment, one or more of the coagents could be added to the formulations 55-58 in one of the compartments 71-73 and one or more of the other coagents would be present in the formulation 58 in the compartment 74. For example, an antibiotic (or another antibacterial agent, antifungal agent, or both) could be present in the formulations 55-57 to prevent bacterial or fungal growth while a protein coagent, such as ALT-C, with or without additional antibiotics, could be present in the formulation 58 in the compartment 74. In a still further embodiment, coagents could be omitted entirely from the device 40, and thus only three compartments 71-73 would be present.
In a further embodiment, to protect the serinoprotease or a coagent (such as ALT-C protein) from degradation, the serinoprotease or the coagent could be microencapsulated in liposomes before being mixed with their respective formulations 56, 58. Liposomes are spherical vesicles having at least one lipid layer that can be created by a disrupting a biological membrane (such as by sonication). The liposomes can continue to encapsulate the serinoprotease, the coagent, or both, until the formulations 56, 58 or both are mixed with contents of other compartments (such as the formulations 55 or 57) that would include a substance that would cause a release of the contents of the liposomes (such as a detergent that would not denature the proteins encountered or interfere with the polymerization reaction).
In addition to including a substance (fibrinogen, serinoprotease, calcium (or another essential ion that could be used as a cofactor for the polymerization reaction), or one or more coagents) to be used directly in the formation of a fibrin polymer (also referred to as “biopolymer formation substances” in the description below), each of the formulations 55-58 includes one or more components that make up a “carrier” for the biopolymer formation substances in that formulation 55-58. In one embodiment, such carrier can be a substance (such as an emulsion) that is dispensed as a foam from the device 40 using one or more propellants described below, with a biopolymer formation substance being part of the foam-forming substance. For example, in addition to a biopolymer formation substance, such foam-forming substance can include water and one or more components commonly used to make foams that come in contact with human skin, such as stearic acid, myristic acid, potassium hydroxide, coconut acid, glycerin, triethanolamine, and sodium hydroxide, though other components are also possible. The ratios of the components in the foam-forming substance necessary to create the foam suitable for contact with human skin are known in the art, such as described in U.S. Pat. No. 4,111,827, issued Sep. 5, 1978 to Thompson et al. and U.S. Pat. No. 5,902,779, issued May 11, 1999, to Cormier et al., the disclosures of which are incorporated by reference, though still other components and their ratios are possible.
Alternatively to foam-forming substance, the carrier in each formulations 55-58 can be a soft gel suitable for contact with human skin within which a biopolymer formation substance is included. In one embodiment, the gel can be a post-foaming shaving gel, such as one whose composition is described in U.S. Pat. No. 5,858,343, issued Jan. 12, 1999, to Thomas J. Szymczak, the disclosure of which is incorporated by reference, though other post-foaming shaving gels known in the art could be used. While a post-foaming shaving gel is not dispensed as a foam, when rubbed against a person's skin, such gel tends to form foam, which can promote mixing of the biopolymer formation substances from different formulations 55-58 when the formulations 55-58 are mixed together on a patient's skin as described below. In a further embodiment, the soft gel could be without foaming properties and be made through a mixing of water, a biopolymer formation substance, and one or more gelling agents known in the art, such as natural gums, starches, pectins, agar-agar, gelatin, and other gelling agent, with the gelling agents being added using concentrations known in the art to create a gel of a desired viscosity. Still other kinds of soft gels are possible.
As viscosity of substances that form foams when dispensed and of gels of different compositions can be different, the same carrier is used in all of the formulations 55-58 to ensure that all of the formulations have the same or substantially the same viscosity and thus escape from the device 40 at the same or substantially the same rate. The carrier that is used is more viscous than water, which, as described below, allows for greater control of how the manner of the fibrin biopolymer formation.
The hollow rods 47-50 are integrated into the actuator 41 and each of the hollow rods 47-50 are connected by a passage 71 to one of the orifices 42-45. Each of the compartments further includes a valve 51 connected to one of the rods 47-50 and that takes a closed position (in which the formulation 55-58 in the compartment 71-74 in which that valve 51 is located is prevented from traveling via one of the hollow rods 47-50 to one of the openings 42-45) and an open position (in which the formulation 55-58 in the compartment 71-74 in which that valve 51 is located has a path to travel via one of the hollow rods 47-50 to one of the openings 42-45). The valves 51 can be secured within the housing using a plurality of techniques known in the art, such as using a mountain cup (not shown) that would fit around the hollow rods 47-50, such as a cup described in U.S. Pat. No. 4,111,339, issued Sep. 5, 1978 to Schmidt, the disclosure of which is incorporated by reference, though other ways to secure the valves 51 within the housing 46 are possible.
While a particular configuration of the valves 51 is described below, other configurations of the valves 51 could also be used, such as those described in U.S. Pat. No. 3,391,834, issued Jul. 9, 1968, to Focht, the disclosure of which is incorporated by reference, and U.S. Pat. No. 2,881,908, issued Apr. 14, 1959, to Germain, the disclosure of which is incorporated by reference, though many other valve designs could be used.
While the valves 51 in all of the compartments 71-74 as well as the hollow rods 47-50 connected to the valves 51 and the openings 42-50 connected to those hollow rods 47-50 are identical, for the sake of clarity of the drawings, some of the elements making up the valves 51 and the hollow rods 47-50 have been labeled in only one of the four valves 51 and the hollow rods 47-50.
Each valve 51 includes a valve body 63 that defines a hollow, substantially cuboid (though other shapes are possible) that is fixedly attached within an interior of one the compartments 71-74 and that defines two openings 52, 53. A gasket 64 acts as a top (with reference to the orientation seen with reference to
A dip tube 66 that is formed around the opening 53 on the valve body 63 of each of the valves 51 and extends into one of the formulations 55-58, providing the formulation 55-58 into which the dip tube 66 extends a path into the inside of the valve body 63 on which that tube 66 is formed.
The valve 51 further spring a spring cup 61 that is set within the valve body 63. One end of the spring cup 61 is connected set within a spring 62 that is set at the bottom of the valve body 63 above the opening 53 (in the orientation shown with reference to
The end of the spring cup 61 that is in contact with the gasket 64 in the closed position of the valve is also connected to one of the rods 47-50. The ends of the rods 47-50 that reach into the device housing 46 are not of a uniform length on all sides; thus, one portion 68 of the end is shorter than other portions and does not touch the spring cup 61 (but is of a sufficient length to reach the housing 46, thus preventing any external objects from entering into the housing 46 regardless of the position of the valve) while at least one other portion 69 is longer and is in contact with the spring cup 62 (such as due to being fixedly attached to the cup 61). The disparity in the length of portions 67 of the rods 47-50 creates an opening through which one of the formulations 55-58 can enter into the interior of the hollow rods when the valve 51 switches into the open position.
The switching of the valve 51 from the closed position is accomplished by pressing on the actuator 41.
Returning to
Similarly, when the propellant 59 includes a liquefiable gas, such as isobutane, during manufacturing, the liquid propellants is pushed into the compartments 71-74 in liquid form under a high pressure (being placed on top of the formulations 55-58 when considering the orientation shown with reference to
As mentioned above, the at least one propellant can include at least one compressible gas, at least one liquefiable gas, or a mixture of compressible and liquefiable gases. For the purposes of illustration, in the closed position, the formulations 55-58 is shown as being inside the valve body 63, though other positions are also possible.
The components of the device 40 are made of a material that can withstand the pressure within the compartments 71-74. Thus, the housing 46 and the actuator 46 can be made of tinplate (steel with a layer of tin) or aluminum, though other non-biologically reactive materials are also possible. The valve 51 can be made of a pressure-resistant plastic, though other materials are also possible. With reference to
Pressing the actuator 41 creates four streams of the formulations 55-58 being dispensed from the four openings 42-45. As the openings are set apart from each other, the formulations are deposited on a desired surface (such as a skin of a patient) some distance from each other, and unless other the actuator 41 remains depressed for an extended period of time near the same spot on the skin, the dispensed formulations do not initially mix with each other, as can be seen with reference to
Once the desired amounts of the formulations have been applied using the device 40 to the skin, the patient (or another person applying the formulations 55-58 using the device) can initiate the polymerization reaction by mixing the applied formulations 55-58 either with his or her hand or with another object. While mixing the formulations 55-58, the person has a chance to cover with the mixture the entire area that needs to be covered with the fibrin biopolymer, as can be seen with reference to
When the formulations 55-58 are mixed in equal proportions, the ratio of the concentrations of the serinoprotease to the concentration of the fibrinogen to the concentration of calcium in the resulting mixture are 0.4:1.0:0.6, though other concentration ratios are also possible in a further embodiment. The concentration of any coagents would depend on the kind of a coagent used.
While in the description above, the device 40 is described as being used for treating external wounds, in a further embodiment, with appropriate formulations 55-58, the device 40 could have a hemostatic surgery use for stopping bleeding and sealing cuts as described above.
While the invention has been particularly shown and described as referenced to the embodiments thereof, those skilled in the art will understand that the foregoing and other changes in form and detail may be made therein without departing from the spirit and scope.
