Case for fixing tissue samples for endometrial polyp research.

Abstract

In the field of medical laboratory equipment technology, we provide a case for fixing tissue samples for endometrial polyp research. [Solution] The sample containment groove 5 on the base 1 contains and maintains the shape of the tissue, and the fixative penetrates from below through the micropores at the bottom. The limiter 2 is detachable from the base. The flexible pressing piece of the pressing member is attached to the limiter via a connecting arm and lightly presses the tissue surface from directly above the sample containment groove. The seal lid 4 is sealed to the base, forming a sealed cavity. This ensures stable sample retention and uniform penetration of the fixative, enabling highly structurally complete fixation. Conventionally, when immersing endometrial polyp tissue samples in fixative, their sparse and small structure makes them prone to floating, folding, or mutual adhesion, hindering uniform penetration of the fixative and causing the initial spatial morphology to collapse. This made it difficult to locate the target region in subsequent embedding and sectioning processes, raising concerns about reduced accuracy in pathological analysis.

Description

Technical Field

[0001] This invention belongs to the technical field of medical experimental instruments, and particularly relates to a case for fixing tissue samples for endometrial polyp research.

Background Art

[0002] Endometrial polyp (EP) is a common disease with a high incidence rate (34.9%) in gynecology, especially commonly seen in reproductive-aged women, and has a profound impact on reproductive health. The formation of EP is related to abnormal estrogen, chronic inflammation stimulation, and abnormal progesterone receptor expression, etc. The clinical symptoms mainly include abnormal uterine bleeding, dysmenorrhea, reproductive disorders, etc., and may also cause adverse pregnancy outcomes such as infertility and miscarriage. Currently, hysteroscopic polypectomy is the gold standard for treatment. However, in clinical practice, it faces a major problem of postoperative recurrence. According to research reports, the recurrence rate ranges from 2.5% to 43%, and in some cases, it may even be higher, and is particularly commonly seen in patients with multiple polyps, infertility, or endocrine disorders. Recurrence not only means that patients bear the physical and mental trauma and economic burden caused by reoperation, but may also further damage the endometrial function and worsen the infertility condition. Although its pathogenesis has not been fully elucidated, it is widely considered that factors such as local estrogen level elevation, chronic inflammation, and imbalance between cell proliferation and apoptosis are closely related. Therefore, deeply exploring its pathogenesis is an urgent clinical need to find effective recurrence prevention measures.

[0003] Fibrosis is a prominent pathological feature of polyp tissue, manifesting as excessive accumulation of extracellular matrix and abnormal tissue remodeling. In related mechanistic studies, transforming growth factor-β1 (TGF-β1) and plasminogen activator inhibitor-1 (PAI-1) are thought to play important roles in the activation of myofibroblasts and the promotion of collagen accumulation. Currently, much of the research on endometrial polyp tissue samples relies on conventional fixation methods, namely, methods in which the excised tissue is directly immersed in a container of fixative (for example, fresh endometrial polyp tissue is placed in 10% neutral buffered formalin, with the fixative volume being 10 to 15 times the volume of the tissue). However, with such fixation methods, it is difficult to effectively maintain the spatial morphology of the tissue sample, and especially in polyp tissues with a loose structure or small volume, the uniform penetration of the fixative is easily hindered by floating, folding, or mutual adhesion. Furthermore, if the initial fixation of the tissue is poor during subsequent pathological processing steps such as dehydration, embedding, and sectioning, it may become difficult to position the target area or structural information may be lost. This affects the accuracy of molecular detection results such as immunohistochemistry and in situ hybridization. Therefore, existing tissue fixation methods have certain limitations in terms of guaranteeing the structural integrity of endometrial polyp samples and the reproducibility of experiments. [Overview of the project] [Problems that the invention aims to solve]

[0004] This invention provides a case for fixing tissue samples for endometrial polyp research. It aims to solve the problem in the prior art where endometrial polyp tissue samples float, fold, or stick together during the fixation process, resulting in uneven penetration of the fixative solution, deformation of the tissue structure, and difficulty in positioning the target area. This ensures structural integrity and experimental reproducibility in subsequent dehydration, embedding, sectioning, and molecular detection processes. [Means for solving the problem]

[0005] To achieve the above objective, this invention employs the following technical solution:

[0006] A case for fixing tissue samples for endometrial polyp research, comprising the following:

[0007] A base is provided on the base, on which a sample-holding groove is provided for containing and maintaining the shape of at least one tissue sample, and the bottom of the sample-holding groove is provided with micropores that penetrate the base to allow the fixative to permeate from below upward;

[0008] It is a limiter, which is detachably connected to the base;

[0009] A pressing member, suspended directly above the sample containment groove via a connecting arm attached to the limiter, includes a flexible pressing piece for gently covering the surface of the tissue sample;

[0010] It is a sealing lid, which is sealed and connected to the base to form a sealed cavity.

[0011] The lower surface of the flexible pressing piece, facing the sample containment groove, is provided with multiple minute protrusions to form a liquid flow gap between it and the tissue sample surface.

[0012] The sealing lid is provided with a liquid injection port and a check valve attached to the liquid injection port for maintaining the airtightness of the sealed cavity after liquid injection.

[0013] The side walls of the sample containment groove are stepped inward to allow the tissue sample to settle at the bottom of the groove and be positioned in the center. [Effects of the Invention]

[0014] This invention involves receiving tissue samples in a sample receiving groove with micropores at the bottom, gently covering them with a flexible pressing piece attached to a limiter, and finally sealing them with a sealing lid. This combined structure effectively solves the core problem that small endometrial polyp samples tend to float, fold, or stick together in the fixative. The stepped receiving groove causes the sample to settle towards the center of the groove bottom, pre-stabilizing its shape; the micropores provide a bottom-to-top penetration pathway for the fixative; the flexible pressing piece applies slight pressure, limiting the displacement of the sample without damaging it; and the sealing lid ensures airtightness during the fixation process, reducing volatilization and contamination. The entire solution aims to provide a stable and uniform initial fixation environment for the sample.

[0015] The micro-protrusions on the lower surface of the flexible pressure piece allow for the formation of multiple micrometer-level gaps when the pressure piece covers the sample, thus satisfying the dual requirements of physical constraint and liquid flow. The check valve equipped on the sealing lid is designed to automatically close the injection port after fixative injection with a syringe, simplifying liquid addition operations in a sealed state and maintaining the sealing performance of the cavity. The sample containment groove employs a structure in which the side walls narrow inward in a stepped manner, and is designed for polyp samples with a volume of 5 mm³ or less. It tends to naturally sink due to gravity and settle in the center of the groove bottom. This contributes to the preservation of the initial morphology and provides a convenient basis for subsequent sample orientation and observation.

[0016] Each component of this invention employs a modular, detachable design (such as snap-fitting of the limiter and base, and screw-in connection of the seal lid), facilitating sample removal after fixation and individual cleaning, sterilization, and reuse of each component, thus meeting the standardized operational requirements of the laboratory. By coordinating the initial spatial structure of the sample with the uniform penetration of the fixative, this solution aims to lay a good foundation for subsequent pathological processing processes such as dehydration, embedding, and sectioning, and to reduce structural deformation due to fixation defects, thereby increasing the reliability of accurately identifying fibrotic areas and glandular structures within polyp tissue, and potentially supporting the consistency and reproducibility of relevant molecular marker immunohistochemical detection results. [Brief explanation of the drawing]

[0017] [Figure 1] Figure 1 is a schematic diagram of the overall structure of the present invention. [Figure 2] Figure 2 is a schematic diagram showing the combination of base and limiter. [Figure 3] Figure 3 is a schematic diagram showing the structure of the pressing member. [Modes for carrying out the invention]

[0018] Hereinafter, embodiments of the present invention will be clearly and completely described with reference to the drawings.

[0019] Refer to Figures 1 to 3. This invention provides a case for fixing tissue samples for endometrial polyp research, comprising a base 1, a limiter 2, a pressing member 3, and a sealing lid 4. The base 1 is a rectangular flat plate structure manufactured by injection molding using medical-grade polypropylene material, with an overall thickness of 5 mm. Six independent sample storage grooves 5 are opened on its upper surface, and the six sample storage grooves 5 are uniformly distributed in 2 rows and 3 columns, with a spacing of 6 mm between adjacent sample storage grooves 5. The side walls of each sample storage groove 5 narrow inward in a stepped manner, with the dimensions of the groove opening being 4 mm × 4 mm, the dimensions of the groove bottom being 3 mm × 3 mm, and the groove depth being 3 mm. This structure allows endometrial polyp tissue samples with a volume of 5 mm³ or less to naturally sink to the center of the groove bottom after insertion, maintaining their original spatial shape and preventing them from floating in the fixative due to the sparseness or low density of the tissue.

[0020] Multiple micropores 6 are provided at the bottom of each sample storage groove 5, penetrating the base 1. The micropores 6 have a diameter of 0.2 mm, a distribution density of 20 pores / cm2, and are uniformly arranged in the groove bottom region. The micropores 6 penetrate the upper and lower surfaces of the base 1, allowing the fixative to penetrate from the bottom of the base 1 upwards through the micropores 6 and enter the sample storage groove 5, thus creating an upward penetration pathway. This ensures sufficient contact between the tissue sample bottom and the fixative, improving the uniformity and efficiency of the fixation reaction. Anti-slip pads are provided at each of the four corners of the lower surface of the base 1. The anti-slip pads are made of rubber material and have a textured surface to enhance the stability of the fixing case when placed on a laboratory bench, preventing slipping or tipping during operation. A liquid level observation window is provided on the side wall of the base 1. The liquid level observation window is made of a transparent polycarbonate material that has been molded into place. Through this window, the experimenter can intuitively determine whether the fixative is completely immersed in the tissue sample, thus avoiding partial immobilization of the tissue due to insufficient liquid level.

[0021] Limiter 2 is installed above base 1 and has an overall grid-like frame structure, composed of support ribs that intersect vertically and horizontally. The support ribs are 1 mm wide and 8 mm high, and are manufactured by integral injection molding using medical-grade polystyrene material. Four snap protrusions are provided on the outer edge of limiter 2, and corresponding snap recesses are provided on the upper edge of base 1. Limiter 2 is detachably connected to base 1 by the fitting of the snap protrusions and snap recesses, ensuring that the position of limiter 2 is stable during the fixing process and that lateral displacement and warping do not occur. The surface of the support ribs of limiter 2 is hydrophilic, which reduces surface resistivity and decreases unexpected displacement due to electrostatic adsorption when inserting or removing tissue samples.

[0022] The pressing member 3 includes a flexible pressing piece 301 and a connecting arm. The flexible pressing piece 301 is manufactured by mold molding using medical-grade silicone material, and its planar contour matches the groove opening shape of the sample containment groove 5. Multiple micro-protrusions are provided on the lower surface of the flexible pressing piece 301. The micro-protrusions are arranged in a 4x4 matrix, with each micro-protrusion having a height of 0.1 mm and a diameter of 0.3 mm. Gaps are maintained between the micro-protrusions, and when the flexible pressing piece 301 covers the surface of the tissue sample, multiple micrometer-level channels are formed between the sample and the pressing piece, allowing the fixative to flow freely through these channels. This enables simultaneous infiltration of the upper and lower surfaces of the sample, while limiting the inversion or horizontal movement of the sample in the fixative. The connecting arm is an arched metal wire made of stainless steel with a bending angle of 120°. One end is welded to the edge of the flexible pressing piece 301, and the other end is inserted into a pre-prepared blind hole on the support rib of the limiter 2, forming a secure mechanical connection. Due to the length of the connecting arm and the arched design, the flexible pressing piece 301 is suspended directly above the sample receiving groove 5. After the tissue sample is inserted, the flexible pressing piece 301 gently covers the sample surface by its own weight and the tensile force of the connecting arm, applying a pressure of less than 0.1 N. This is sufficient to prevent buoyancy without compressing the tissue and causing structural collapse or cell destruction.

[0023] The seal cover 4 is made of a transparent rigid plastic material, fabricated from polymethyl methacrylate, and presents a rectangular cover structure as a whole. An annular seal flange is provided at the edge of its lower surface, and the outer diameter of the annular seal flange coincides with the outer diameter of the upper surface edge of the base 1. An external thread is provided on the upper surface edge of the base 1, and an internal thread is provided inside the annular seal flange. The seal cover 4 is tightly connected to the base 1 by a screw-in connection method to form a sealed cavity. This effectively prevents the volatilization of the fixing liquid or the intrusion of external contaminants. A liquid injection port is provided in the central region of the top of the seal cover 4, and a check valve is incorporated in the liquid injection port. The check valve is composed of a silicone valve and a metal spring. When an external syringe needle is inserted, the valve is compressed and opened to enable the injection of the fixing liquid; when the needle is withdrawn, the spring returns the valve to its original position, automatically closing the liquid injection port to maintain the sealing performance of the cavity. A display label area is provided on the inner ceiling surface of the seal cover 4. This area is subjected to a matte finish, and the surface roughness Ra value is 3.2 μm. The experimenter can directly write the sample number, collection time, patient information, etc. in this area with an oil-based marker pen. After being immersed in a common fixing liquid such as 10% neutral buffered formalin for 72 hours, the handwriting can still be clearly read and is not easily dissolved or erased.

[0024] During use, first place base 1 flat on the workbench, ensuring the anti-slip pads make contact with the surface for stable support. Open limiter 2 and remove it from base 1. Using sterile forceps, place endometrial polyp tissue samples one by one into the corresponding sample storage grooves 5. The tissue will naturally settle to the bottom of the groove due to gravity and be centered by the stepped side walls. Next, reattach limiter 2 to base 1 and secure it firmly with the snap mechanism. At this point, each flexible pressure piece 301 is stopped directly above each sample storage groove 5 by the traction force of the connecting arm. Inject a sufficient amount of fixative solution. The liquid level should exceed the upper edge of the sample storage groove 5. The fixative solution penetrates from the bottom through the micropores 6 and infiltrates the tissue sample from above through the micro-protrusion gaps on the lower surface of the flexible pressure piece 301. Screw on seal lid 4, ensuring the cavity is completely sealed by the screw connection, and the check valve closes automatically after injection is complete. The experimenter can check the liquid level through the liquid level observation window and record the necessary information in the display label area. The fixation process typically lasts from 6 to 24 hours, during which time the tissue sample remains stable, moist, and free from folding or sticking. After fixation is complete, the seal lid 4 is loosened and opened, the pressing member 3 and limiter 2 are removed in that order, and the tissue sample is taken out with tweezers to proceed to subsequent dehydration, embedding, sectioning, and molecular detection procedures. The base 1, limiter 2, pressing member 3, and seal lid 4 are all reusable after high-temperature, high-pressure sterilization and meet standardized laboratory operating requirements.

[0025] This invention is designed such that through the coordinated design of the stepped sample accommodation groove 5 and the bottom micropores 6 on the base 1, after the insertion of minute and sparse endometrioid polyp tissue samples, they automatically adhere closely to the groove bottom to prevent floating; through the combined structure of the limiter 2 and the pressing member 3, a controlled slight covering pressure is applied to the sample to prevent folding, inversion, or mutual adhesion; the minute bumps on the lower surface of the flexible pressing piece 301 limit the displacement of the sample and at the same time maintain the liquid exchange path; the fixing liquid penetrates from below to above through the micropores 6 and completes all-round infiltration through the pressing piece gap; the screw connection and check valve structure of the sealing lid 4 ensure that the fixing process is carried out in a sealed environment; the overall structure is modular, detachable, easy to clean, and reusable. Each of the above components acts jointly to ensure the integrity of the spatial configuration in the initial fixing stage of the tissue sample, provide a highly reliable basis for the accurate identification of the fibrotic area, glandular structure, and stromal components in subsequent pathological sections, and thus assist in the accurate detection of major molecular markers such as PAI-1, TGF-β1, α-smooth muscle actin, and collagen in immunohistochemical staining.

Explanation of Reference Numerals

[0026] 1 Base 2 Limiter 3 Pressing Member 3 Sub-item 1 Flexible Pressing Piece 4 Sealing Lid 5 Sample Accommodation Groove 6 Micropores

Claims

1. A case for fixing tissue samples for endometrial polyp research, A base is provided on the base, on which a sample-holding groove is provided for containing and maintaining the shape of at least one tissue sample, and the bottom of the sample-holding groove is provided with micropores that penetrate the base to allow a fixative to permeate from below upward; It is a limiter and is detachably connected to the base; A pressing member, suspended directly above the sample storage groove via a connecting arm attached to the limiter, and including a flexible pressing piece for gently covering the surface of the tissue sample; It is a sealing lid, which is sealed and connected to the base to form a sealed cavity; A case for fixing tissue samples for endometrial polyp research, characterized by the following features.

2. The lower surface of the flexible pressing piece facing the sample containment groove is provided with a plurality of minute protrusions to form a liquid flow gap between it and the tissue sample surface. The case for fixing tissue samples for endometrial polyp research as described in feature 1.

3. The sealing lid is provided with a liquid injection port and a check valve attached to the liquid injection port for maintaining the airtightness of the sealed cavity after liquid injection. The case for fixing tissue samples for endometrial polyp research as described in feature 1.

4. The side walls of the sample-receiving groove are stepped inward to allow the tissue sample to settle at the bottom of the groove and be positioned in the center. The case for fixing tissue samples for endometrial polyp research as described in feature 1.

Images