Dead body preservation liquid

Abstract

To provide a dead body preservation liquid capable of preserving a dead body for a long term by preventing occurrence of mold.SOLUTION: A dead body preservation liquid contains aliphatic aldehyde, methanol, and cationic antimicrobial agent.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a mortuary preservation solution. [Background technology]

[0002] Embalming is known as a technique for sanitizing and preserving a body for a long period of time by sterilizing, disinfecting, preserving, and repairing the body. This embalming technique is used not only for people as mentioned above, but also for pets, human specimens, animal specimens, etc.

[0003] An example of embalming technology is the method of fixing a corpse described in Patent Document 1. In Patent Document 1, a fixative is injected into at least four locations of the corpse: the esophagus, the abdominal cavity, the thoracic cavity, and around the lower jaw. This fixative contains at least one aliphatic aldehyde, at least one lower alkanol, and water as essential ingredients. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-282630 Summary of the Invention [Problem to be solved by the invention]

[0005] However, with conventional corpse fixatives, such as those used in Patent Document 1, when a corpse is preserved for a long period of time, for example as a specimen, mold grows, making it impossible to preserve the specimen for that long period of time. One possible cause of this is that the water contained in the corpse fixative creates an environment in which mold-causing microorganisms attached to the corpse can easily grow, causing mold to grow. Moldy specimens make it impossible to conduct research or other studies, resulting in the loss of valuable materials.

[0006] The present invention has been made in consideration of the above-mentioned problems, and its main object is to provide a body preservation solution that can prevent the growth of mold and preserve bodies for long periods of time. [Means for solving the problem]

[0007] The preservation solution of the present invention is characterized by containing an aliphatic aldehyde, methanol, and a cationic antibacterial agent.

[0008] With the above-mentioned configuration, the cationic antibacterial agent is contained in the preservation solution, and the cationic antibacterial action broadens the antibacterial spectrum, providing a sterilizing effect against a wide range of microorganisms, including bacteria, fungi, mold, etc. Therefore, even if mold-causing microorganisms are attached to the body, the cationic antibacterial agent can reduce the number of those microorganisms and prevent the growth of mold.

[0009] In one specific embodiment of the preservation solution of the present invention, the cationic antibacterial agent is contained in an amount of 0.001% by weight or more and 0.05% by weight or less.

[0010] While cationic antibacterial agents have the bactericidal effect described above, they also destroy cell membranes and denature proteins due to the hydrophobic-hydrophilic interactions resulting from their cations (positive charge) and molecular structure. For this reason, they have not been used in traditional embalming solutions due to the risk of damaging the body. However, if the cationic antibacterial agent is added in a concentration of between 0.001% and 0.05% by weight, it can be used in embalming solutions without damaging the body and can prevent mold growth, allowing the body to be preserved.

[0011] In one specific embodiment of the preservation solution of the present invention, the cationic antibacterial agent is polyhexamethylene biguanide.

[0012] In one specific embodiment of the preservation solution of the present invention, the aliphatic aldehyde is contained in an amount of 10% by weight or more and 25% by weight or less, and the methanol is contained in an amount of 25% by weight or more and 70% by weight or less. [Effects of the Invention]

[0013] According to the present invention, it is possible to provide a body preservation solution that can prevent the growth of mold and preserve bodies for long periods of time. [Brief explanation of the drawings]

[0014] [Figure 1] Photographs of the abdominal cavity of a dog using the body preservation solution of this embodiment. [Figure 2] Photographs of the inside of the body cavity of a rat using the body preservation solution of this embodiment. [Figure 3] HE stained image of tissue specimen fixed with EPM solution. [Figure 4] 1 shows an HE stained image of a tissue specimen prepared using the body preservation solution of the present embodiment. [Figure 5] Immunohistochemistry using TAPA-1 antibody on kidney tissue specimens prepared using the preservation solution of this embodiment. [Figure 6] Immunohistochemistry using TAPA-1 antibody on lung tissue specimens prepared using the preservation solution of this embodiment. [Figure 7] Immunohistochemistry using NF200 antibody on a brain tissue specimen prepared using the preservation solution of this embodiment. [Figure 8] Immunohistochemistry using GFAP antibody on a brain tissue specimen prepared using the preservation solution of this embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0015] An embodiment of the body preservation solution of the present invention will be described in detail below.

[0016] The body preservation solution of this embodiment is injected into a body and is used for embalming to sanitarily preserve the body.

[0017] The preservation solution contains an aliphatic aldehyde, methanol, and a cationic antibacterial agent.

[0018] The aliphatic aldehyde acts on the functional groups of proteins to form intramolecular or intermolecular crosslinks, thereby immobilizing the body. The aliphatic aldehyde is preferably selected from the group consisting of aliphatic monoaldehydes and aliphatic dialdehydes.

[0019] Examples of the aliphatic monoaldehyde include linear or branched monoaldehydes having 1 to 5 carbon atoms, such as formaldehyde, paraformaldehyde or formalin, acetaldehyde, propionaldehyde, butyraldehyde, isobutyraldehyde, valeraldehyde, isovaleraldehyde, glyoxylic acid (HOOC-CHO), and acrolein.

[0020] Examples of the aliphatic dialdehyde include straight-chain or branched dialdehydes having 2 to 6 carbon atoms, such as glyoxal, malonaldehyde, succinaldehyde, glutaraldehyde, and adipaldehyde.

[0021] A preferred aliphatic aldehyde for use in the preservation solution of this embodiment is glyoxal.

[0022] Cationic antibacterial agents have antibacterial properties (here, "antibacterial" refers to the general state of inhibiting bacterial growth, such as killing bacteria, disinfecting, and sterilizing) by destroying cell membranes and denaturing proteins through hydrophobic and hydrophilic interactions derived from their cations (positive charge) and molecular structure, thereby preventing the growth of mold.

[0023] Examples of cationic antibacterial agents include quaternary ammonium salts (e.g., alkyltrimethylammonium salts, polyoxyethylene alkylmethylammonium salts), guanidine antibacterial agents (e.g., chlorhexidine gluconate, chlorhexidine hydrochloride), biguanide antibacterial agents (e.g., polyaminopropyl biguanide, polyhexamethylene biguanide (PHMB)), metal ion carriers (e.g., metal salts such as silver nitrate and copper sulfate that can release metal ions such as silver ions and copper ions), hexetidine, and metallonidazole.

[0024] A preferred cationic antibacterial agent for use in the preservation solution of this embodiment is polyhexamethylene biguanide (PHMB).

[0025] In the preservation solution of this embodiment formulated as described above, the cationic antibacterial agent is contained in an amount of 0.001% by weight or more and 0.05% by weight or less, the aliphatic aldehyde is contained in an amount of 10% by weight or more and 25% by weight or less, and the methanol is contained in an amount of 25% by weight or more and 70% by weight or less.

[0026] The cationic antibacterial agent is preferably present in a concentration of 0.01% by weight to 0.05% by weight. At concentrations below 0.01% by weight, the antibacterial effect of the cationic antibacterial agent is weak, potentially leading to mold growth. At concentrations above 0.05% by weight, the cationic antibacterial agent may cause protein denaturation, potentially resulting in denaturation of the corpse. Furthermore, when polyhexamethylene biguanide (PHMB) is used as the cationic antibacterial agent, toxicity to the human body has been confirmed at concentrations above 1000 ppm (0.1% by weight). Therefore, a concentration of 0.01% by weight to 0.05% by weight is more preferable, as this range allows users to use the preservation solution safely and still obtain its effectiveness.

[0027] The preservation solution of this embodiment, configured as described above, contains a cationic antibacterial agent, which broadens the antibacterial spectrum and has a sterilizing effect against a wide range of microorganisms, including bacteria, fungi, mold, etc. Therefore, even if mold-causing microorganisms are attached to the body, the cationic antibacterial agent can reduce the number of those microorganisms and prevent the growth of mold.

[0028] Furthermore, while cationic antibacterial agents have a bactericidal effect, they also destroy cell membranes and denature proteins due to the hydrophobic-hydrophilic interactions resulting from their cations (positive charges) and molecular structure. However, if the content of cationic antibacterial agents is between 0.001% and 0.05% by weight, the presence of cationic antibacterial agents in the preservation solution will not damage the body and will prevent mold growth, allowing the body to be preserved.

[0029] In addition, since the body preservation solution of this embodiment does not use formalin, users can use the body preservation solution of this embodiment to preserve bodies or prepare specimens using the bodies without being exposed to the toxicity of formalin.

[0030] The present invention can be modified in various ways without departing from the spirit of the invention. [Example]

[0031] The present invention will be described in more detail below with reference to examples, but the scope of the present invention is not limited to these examples.

[0032] The following two tests were carried out to test the usefulness of the present invention. (1) Mold growth test using the body preservation solution of this embodiment (2) Histological analysis of organs using the preservation solution of this embodiment

[0033] The following describes "(1) Mold growth test using the body preservation solution of this embodiment." <Exam Preparation> The specimens used were a dog (beagle, 14 months old, n=1) and a rat (Wistar, 4 months old, n=3). The preservation solution used for the specimen in this embodiment contains an aliphatic aldehyde, methanol, and a cationic antibacterial agent, and the aliphatic aldehydes used are glyoxal (40% aqueous solution, manufactured by Yoneyama Pharmaceutical Co., Ltd.) and methanol (purity 99.8% or higher, manufactured by Taishin Chemical Co., Ltd.), and the cationic antibacterial agent is polyhexamethylene biguanide (PHMB) (Sparax, supplied by Shimada Shoten Co., Ltd.). The preservation solution of this embodiment contains 95% glyoxal and methanol, and 5% PHMB. The solution contains 0.05% by weight (500 ppm) of PHMB. The glyoxal and methanol are present in proportions of 40% and 60%, respectively, resulting in a total of 15.2% by weight of glyoxal and 57% by weight of methanol.

[0034] <Test Method> The specimens were perfused with saline, then perfused and fixed with the body preservation solution of this embodiment, and then stored at 4°C. The presence or absence of mold growth was checked for one month for rats and four months for dogs.

[0035] <Test Results> Figure 1 is a photograph of the body cavity of a dog after 4 months, and Figure 2 is a photograph of the body cavity of a rat after 1 month. As is clear from the photographs of the body cavities of the dog and rat shown in Figures 1 and 2, no mold growth was observed. Furthermore, in both the dog and rat specimens, no mold growth was observed not only in the body cavity but also on the body surface, indicating that mold growth was inhibited.

[0036] The following describes "(2) Histological analysis of organs using the preservation solution of this embodiment."

[0037] <Exam Preparation> Rats (Wistar, 4 months old, BW 260-310 g, n=12) were prepared as specimens. The preservation solution used for the specimens was the same as that used in test (1).

[0038] <Test Method> The specimens were perfused with the following solutions (a) and (b), and the brain, lungs, kidneys, and spleen were removed. Each organ was then immersed and fixed for another 24 hours before paraffin sections were prepared. The paraffin sections were stained with hematoxylin and eosin (HE) to prepare tissue specimens. Furthermore, the paraffin sections prepared using solution (b) were subjected to immunohistochemistry according to standard methods. (a) Ethylene glycol, phenol, and methanol mixture (hereafter referred to as "EPM fixative") (b) Preservation solution of this embodiment

[0039] <Test Results> For histological analysis, histological morphology and immunohistochemistry of the tissue specimens were analyzed.

[0040] Histological analysis (a) When EPM fixative was used Figure 3 shows HE-stained images of tissue specimens prepared using EPM fixative. The image on the left side of Figure 3 is a tissue specimen related to the kidney and renal cortex, and the image on the right side of Figure 3 is a tissue specimen related to the spleen. Compared to the case where the preservation solution of the present embodiment described below was used (Figure 4), as shown in Figure 3, the tissue morphology was unclear and the eosin staining was strong. (b) When the body preservation solution of this embodiment is used Figure 4 shows HE-stained images of tissue specimens prepared using the preservation solution (b) of this embodiment. The image on the left side of Figure 4 is a tissue specimen related to the kidney and renal cortex, and the image on the right side of Figure 4 is a tissue specimen related to the spleen. As shown in Figure 4, in all of the kidney, renal cortex, and spleen, the morphology of the tissue and nuclei was maintained to the same extent as in the case of immersion fixation using the conventional 10% formalin solution, and the staining properties of the HE stain were also good.

[0041] -Immune tissue analysis Immune tissue analysis was performed using the preservation solution of this embodiment. Immunohistochemical analysis was performed using antibodies against TAPA-1 for the lungs and kidneys, and NF200 or GFAP for the brain. The results for the kidneys are shown in Figure 5, those for the lungs in Figure 6, and those for the brain in Figures 7 and 8. As shown in Figures 5 to 8, positive expression was observed in specific tissue regions indicated by black arrows in all tissue specimens. Furthermore, the cell morphology of neurons was also very clearly observed.

[0042] In this example, the following results were obtained. In other words, no mold was observed on the body surface or in the body cavity even after one month in rats and four months in dogs after perfusion fixation with the preservation solution of this embodiment. Furthermore, even when the preservation solution of this embodiment was used, the histological morphology was maintained, and the suitability for immunohistochemistry was also confirmed.

[0043] Therefore, the body preservation solution of this embodiment can prevent mold from growing on the body due to the antibacterial action of the cationic antibacterial agent, and can be used not only for short-term preservation of bodies but also for preparing specimens for macroscopic dissection practice and tissue specimens for long-term preservation of bodies.

[0044] Furthermore, cationic antibacterial agents can cause cell membrane destruction and protein denaturation due to hydrophobic-hydrophilic interactions resulting from their cations (positive charges) and molecular structure. However, specimens prepared using the preservation solution of this embodiment did not experience cell membrane destruction or protein denaturation. This is because the cationic antibacterial agent contained in the preservation solution of this embodiment is between 0.01% and 0.05% by weight, which minimizes the extent of cell membrane destruction and protein denaturation caused by the cationic antibacterial agent and prevents the preparation of specimens.

Claims

1. A preservation solution containing an aliphatic aldehyde, methanol, and a cationic antibacterial agent.

2. 2. The embalming solution according to claim 1, wherein the cationic antibacterial agent is contained in an amount of 0.001% by weight or more and 0.05% by weight or less.

3. 3. The body preservation solution according to claim 1, wherein the cationic antibacterial agent is polyhexamethylene biguanide.

4. The aliphatic aldehyde is contained in an amount of 10% by weight or more and 25% by weight or less, 3. The body preservation solution according to claim 1, wherein the methanol is contained in an amount of 25% by weight or more and 70% by weight or less.

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