Inhalation toxicology experiment system and experiment method for animals

Abstract

The invention provides an inhalation toxicology experiment system and experiment method for animals, and aims to evaluate the influence of drugs on the animals. According to the system, an integrated head-mounted bandage is fixed to the face of an animal, so that a biological electrode is in contact with the skin of the face of the animal, and electromyographic signals are collected. And the signal is wirelessly transmitted to the monitoring terminal through the control box, so that remote monitoring is realized. In an experiment, medicine is added into the aerosol generator and converted into fine particles, the fine particles are sent into the exposure box through the air supply device, and animals are exposed in the environment for a certain time. During the period, the system continuously monitors the aerosol concentration and the environmental oxygen content to ensure stable experimental conditions. And the toxic effect of the medicine is analyzed by comparing the change of the electromyographic signals of the control group and the experimental group. An advanced signal processing technology, such as band-pass filtering, independent component analysis and the like, is adopted to extract features from the electromyographic signals, and a classifier is trained by using a machine learning method to distinguish normal electromyographic signals from electromyographic signals influenced by drugs, so that the accuracy and reliability of experimental results are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of toxicology experiments, and is used for testing drug smoking of living animals and performing toxicology experiment analysis and data analysis, and particularly relates to an inhalation toxicity experiment system for animals and an experiment method. BACKGROUND

[0002] Inhalation toxicity testing is an experimental method for assessing the potential health effects of chemicals, drugs or environmental pollutants entering the body through the respiratory system. Such testing is crucial for understanding potential risks in the fields of occupational safety, environmental protection and new drug development. Inhalation toxicity testing aims to simulate the situation in which humans or animals passively or actively inhale corresponding drug components through the respiratory tract in actual exposure scenarios, and assess the impact of physiological changes. Traditionally, inhalation toxicity testing mainly uses mice, rats and other animals as models. Animals are placed in specially designed inhalation exposure chambers, where the concentration of harmful substances in the air is strictly controlled. However, if the study involves the physiological response of drugs after smoking, small animals such as rats are not suitable, and larger animals such as cows, sheep, monkeys or pigs are usually needed for experiments. However, primate experimental animals are expensive and cost high. In the prior art, such as the biological safety type primate large animal biological aerosol oral-nasal exposure system disclosed in CN109512545B, the system is only for primate experiments, and cannot be used when pigs are used. In addition, if the electromyographic signal of the animal in the inhalation toxicity experiment is to be obtained, the animal's movement cannot be restricted, and the animal's activity needs to be restricted in the prior art to make it passively smoke toxic gas. Such restrictions will cause the animal to instinctively resist and move, and these unnecessary movements will affect the noise of electromyographic signal collection and affect the collected data. Therefore, it is not suitable for pigs as experimental objects.

[0003] However, the existing installation process of biological electrodes has many inconveniences:

[0004] Exposed and messy wires: traditional electrodes often have relatively long wires that extend from the skin surface to connect to data acquisition devices. Not only do these wires look messy and disorganized, but they are also prone to physical interference, such as being scratched or bitten off by animals.

[0005] Poor fixation: electrodes are usually attached to the skin or facial muscles of animals using adhesive tape or other adhesives. While this is a common practice, it is not always strong enough. The natural movement of animals can cause the tape to loosen or fall off, especially when monitoring for a long time or when the animal sweats. If the electrodes move or even completely detach from their original position due to these reasons, it will affect the quality of signal collection, cause data loss or generate noise, making the collected information unreliable.

[0006] Time-consuming and tedious: each experiment needs to be repositioned and pasted electrodes before starting, which is a time-consuming and tedious process. Especially for those studies that need to be tested multiple times to obtain reliable data, this process will significantly increase the overall workload and is extremely inconvenient.

[0007] Therefore, there is currently a lack of a flexible and efficient system and method for collecting animal electromyographic signals for toxicology experiments. SUMMARY

[0008] In order to solve the above-mentioned deficiencies and shortcomings of the prior art, the inventor has made innovative designs to provide a new experimental system for inhalation toxicology of animals such as cattle, sheep and pigs, which integrates aerosol atomization processing equipment, liquid medicine adding equipment, air sending and distributing equipment, internal environment monitoring technology and exhaust filtering equipment. The experimental operation is convenient and safe, and the animals can be in a natural activity state in the exposure box without restraint equipment, which facilitates the real, stable and reliable collection of animal physiological response data.

[0009] Specifically, the present application is implemented as follows: an inhalation toxicology experiment system for animals, comprising: an exposure box (1), a sealed box body structure with a door body, used for placing animals to be tested, a gas inlet (11) is installed at the front end of the box body, the gas inlet (11) is connected to an aerosol generator (2) and an air supply device (3); the aerosol generator (2) is used for converting liquid or solid drugs into fine particle mist or aerosol for inhalation by the animals to be tested; it comprises a drug delivery tube (21), an ultrasonic atomizer or a rotary atomizer (22) in communication with the bottom of the drug delivery tube (21), and the gas outlet end of the ultrasonic atomizer or the rotary atomizer (22) is in communication with the gas inlet (11); the air supply device (3) passively or actively provides air, and comprises a fan (31) and an air supply pipeline (32), the air supply pipeline (32) is connected to the air inlet end of the ultrasonic atomizer or the rotary atomizer (22); a monitoring module (4) comprising an oxygen content sensor and an aerosol concentration detector is installed at the top inside the exposure box (1) and connected to a monitoring terminal by wired or wireless communication; the monitoring terminal is used to display the current oxygen content data and aerosol concentration data in the exposure box (1); an exhaust filter device (5) is installed on the top of the exposure box (1) in a passive exhaust or active exhaust manner, comprising a filter, and the gas is discharged to the outside of the exposure box (1) after passing through the filter; an integrated headband (70) is used to wear on the head of the animal, a plurality of bioelectrodes (71) are installed on the inside of the animal's face area on the headband, used for collecting bioelectric signals, and each bioelectrode (71) is connected to a control box (72) through a wire (78) integrated on the headband; the control box (72) is installed on the headband above the animal's head area, and has a built-in battery, a data receiving unit and a wireless communication unit, the data receiving unit is connected to the wire (78), the wireless communication unit is connected to the data receiving unit, and the collected data can be transmitted to the monitoring terminal; the monitoring terminal is connected to the aerosol generator (2), the air supply device (3), the exhaust filter device (5), the monitoring module (4) and the control box (72), can collect and record the data information transmitted by each component, and can issue monitoring operation instructions.

[0010] Further, the exposure box (1) is in the form of a rectangular box structure, one end is provided with a lock door body (12), and the other end is externally provided with an operation box, the operation box is internally provided with the fan (31) and the aerosol generator (2), the fan (31) is connected to the aerosol generator (2) through the air supply pipeline (32), the aerosol generator (2) comprises a drug tube and an ultrasonic atomizer or a rotary atomizer (22), the gas inlet (11) is the gas outlet nozzle of the ultrasonic atomizer or the rotary atomizer (22), and directly extends into the inside of the exposure box (1).

[0011] Furthermore, the oxygen content sensor and aerosol concentration detector are installed in the middle of the top of the exposure box (1). The oxygen content sensor and aerosol concentration detector are connected by a data wire to achieve power supply and data transmission, or data transmission is achieved through a built-in battery via a wireless signal transmission module. The aerosol generator (2), the air supply device (3), and the exhaust filter device (5) are all directly powered by a power supply connected by a wire.

[0012] Furthermore, the filter includes a replaceable filter element (51), which is installed inside the filter box. The filter box is installed below the exhaust hood (52) and directly connected to the exhaust outlet at the top of the exposure box (1). An exhaust fan (53) is installed above the exhaust hood (52). The exhaust fan (53) is connected to the monitoring terminal via a wire and can draw gas from the exposure box (1). The monitoring terminal is connected to a power source and is connected to various components via wires. It is connected to the monitoring module (4) and can control the start and stop of the aerosol generator (2), the start and stop of the fan (31) of the air supply device (3), and the start and stop of the exhaust filter device (5).

[0013] Furthermore, the integrated headband (70) includes: a main nose ring (73) that can be connected in a ring shape for fitting and binding the nasal turbinates and lower part of the animal's head; and a secondary head ring (74) that is divided into two sections, left and right, with one end of each section fixedly connected to the upper middle part of the main nose ring (73), and the other end wrapping around the ear and then connecting to the lower side of the main nose ring (73).

[0014] Furthermore, the two ends of the main nose ring (73) are provided with first fastening components (75), which can be connected and fixed or opened to facilitate wearing; the other end of the auxiliary head ring (74) is connected to the lower side of the main nose ring (73) through a second fastening component (76) for adjusting the length of the auxiliary head ring (74); the first fastening component (75) and the second fastening component (76) can both include Velcro kits at both ends, which are glued together, or a buckle with a pin at one end and several holes arranged on the other end.

[0015] Furthermore, the control box (72) is installed on the secondary head ring (74), and the wire (78) is embedded in the main nose ring (73) or the secondary head ring (74), or sewn or attached to the surface of the main nose ring (73) or the secondary head ring (74); the bioelectrode (71) is a dry electrode or a gel electrode, and the bioelectrode (71) is located inside the main nose ring (73) or the secondary head ring (74) in the orbicularis oculi muscle, frontalis muscle or buccinator muscle area of ​​the animal's head; the collar (79) is connected to the top of the secondary head ring (74) and the bottom of the main nose ring (73), and has a third fastening component at both ends for wearing on the animal's neck.

[0016] Furthermore, it also includes a mask (80), which is detachably mounted on the main nose ring (73). The shape and size of the mask (80) can cover the animal's mouth and nose area. The tail end of the mask (80) is connected to a ventilation tube. The ventilation tube is connected to the air supply device or directly connected to the air outlet of the ultrasonic atomizer or rotary atomizer (22).

[0017] Another aspect of the present invention provides an experimental method for an inhalation toxicology testing system, comprising the following steps:

[0018] Step s1: Wear the integrated headband (70) on the animal's face, and make several bioelectrodes (71) on the inner side of the animal's face area directly contact the facial skin, and fix the tightness of the band to make it secure.

[0019] Step S2: The bioelectrode (71) is connected to the control box (72) on the strap located above the animal's head via a wire. The control box (72) is connected to the data receiving unit via a wireless communication unit and sends the collected electromyographic signal data to the monitoring terminal.

[0020] Step S3: Add the liquid or solid drug used in the experiment to the aerosol generator (2) in a quantitative amount and ensure that the aerosol generator (2) is in standby mode.

[0021] Step S4: Place the animal in an exposure box (1), and connect the air inlet (11) in the exposure box (1) to the aerosol generator (2) and the air supply device (3);

[0022] Step S5: The monitoring terminal can receive and store the real-time electromyographic signals collected by the bioelectrode (71).

[0023] Step S6: After the aerosol generator (2) is started, it can be converted into fine particulate mist or aerosol. The mist or aerosol containing drug components is mixed with air and injected into the exposure box (1). The running time information of the aerosol generator, the exposure time, the concentration of the mixed gas, the drug dosage information, and the starting time information of animal inhalation are recorded.

[0024] Step S7: Collect electromyographic signal data detected by the complete bioelectrode (71) during the experiment; and transmit it to the monitoring terminal for analysis and processing;

[0025] Among them: bioelectrodes (71) are distributed on the orbicularis oculi muscle, frontalis muscle or cheek muscle area of ​​the animal; the monitoring module (4) monitors the oxygen content data and aerosol concentration data in the exposure box (1) in real time through oxygen content sensor and aerosol concentration detector; when the oxygen content data or aerosol concentration data exceeds or falls below the set value, an alarm will be activated.

[0026] Further steps include: setting up a control group and an experimental group, ensuring that the two groups are completely identical except for whether they are exposed to the toxin; the control group does not add any drug components to the aerosol generator (2) and uses pure water as a control, while the experimental group adds drug components to the aerosol generator (2). Before starting the aerosol generator (2), normal electromyographic signals are collected for a period of time as baseline data for the control group and the experimental group; the experimental group animals are exposed to different concentrations or doses of drug components in stages, with sufficient time intervals between each stage to observe and record changes in electromyographic signals; at the end of each stage, the electromyographic signals are recorded repeatedly to increase the reliability and statistical power of the data; Bandpass filters were applied to remove noise in unwanted frequency ranges, and independent component analysis (ICA) was used to separate electromyographic (EMG) signal components related to toxicant exposure. All signal intensities were normalized to the same scale for comparison. The mean, variance, and peak value of the EMG signals were calculated, and the spectrum of the signals was obtained through Fourier transform to analyze the energy distribution at specific frequencies. Based on the extracted features, a classifier was trained to distinguish EMG signals under normal activity and toxicant influence. Cross-validation was used to evaluate the model performance, ensuring high accuracy even on unseen data. The results of the experimental group and the control group were compared to analyze the changing trends of EMG signals before and after toxicant exposure.

[0027] The working principle of this invention is as follows: Liquid or solid drugs are converted into tiny particles (aerosols) using an ultrasonic nebulizer or rotary nebulizer, and then mixed with air before being directly introduced into the exposure chamber. Ultrasonic nebulization generates tiny droplets by vibrating the liquid surface with high-frequency sound waves; rotary nebulization centrifuges the liquid using a high-speed rotating disc or nozzle. This ensures that the drug forms fine particles suitable for animal inhalation, increasing lung absorption efficiency. The air supply device (including a fan and air ducts) actively provides a stable airflow, mixing the aerosol with the airflow and actively introducing it into the exposure chamber. This airflow is evenly distributed within the chamber, ensuring that the animals being tested can inhale the aerosol uniformly while maintaining adequate oxygen levels and preventing hypoxia. Simultaneously, the exhaust filtration device uses a suction fan to expel waste gas from the chamber, maintaining fresh air inside, and removes harmful substances through filters (such as activated carbon, HEPA filters, etc.), protecting the experimental environment. The monitoring module includes an oxygen sensor and an aerosol concentration detector that monitor the gas composition and concentration within the exposure chamber in real time, ensuring that experimental conditions meet requirements and preventing animal injury due to insufficient oxygen or excessive drug concentration. The monitoring terminal receives this data and adjusts the operation of the aerosol generator, air supply device, and exhaust filtration device accordingly, enabling automatic or manual remote control. The exposure chamber is designed with both animal safety and researcher convenience in mind, featuring a transparent observation panel for easy monitoring of animal reactions, bottom rollers for easy movement, a storage compartment within the chamber for convenient storage, and volume markings on drug tubes for accurate drug administration. An integrated headband is used to stably position bioelectrodes in key muscle areas of an animal's head (such as the orbicularis oculi, frontalis, or buccinator muscles) to collect electromyographic signal data after the animal ingests toxic substances for experimental data acquisition. The combination of a main nose ring and secondary headbands provides a more even pressure distribution and ensures stable wear on the animal's head. The main nose ring is worn around the animal's cheek to below the jaw, while the secondary headbands are worn behind the ears, forming a triangular area on the animal's face. The control box, serving as a centralized area for circuit board components and batteries, houses a power supply, data receiving unit, and wireless communication unit. It processes the collected data in real-time (using circuit design to reduce noise, amplify, convert, and transmit signals) and wirelessly transmits it to a remote monitoring computer or other terminal equipment. Because the wires are integrated with or embedded within the wearing ring, no additional physical connection cables are required, reducing potential interference from animal activity. The main nose collar and the secondary head collar are fitted with adjustable fastening components. The design can use Velcro or buckles with holes to facilitate quick adjustment of the strap tightness. This ensures a secure fit while effectively fixing the electrode position so that it adheres tightly to the animal's facial skin, preventing displacement due to animal movement that could affect data accuracy.The main nose ring and secondary head ring are made of silicone, which is soft and biocompatible. Textile straps are lightweight and breathable while providing tension. Combining both and adding elastic bands or fabric at appropriate locations enhances elasticity and improves wearing stability, facilitating stable monitoring over extended periods. Different types of electrodes are selected based on actual needs: dry electrodes are suitable for frequent replacements and are easy to clean and maintain; while gel electrodes provide better skin contact, contributing to a more stable electrical signal. The collar is an optional component, adding an extra support point to help distribute pressure across the entire device, making the overall structure more stable. It also serves as a backup, using a mountable design to create stress points from the bottom of the main nose ring and the top of the secondary head ring, further improving wearing stability and secureness. Masks and ventilation tubes are also optional accessories. For certain research scenarios, such as when the amount of drug gas inhaled needs to be guaranteed, a mask is installed and the experimental gas containing the drug is injected through the ventilation tube. The gas enters the mask through the ventilation tube and can be fully and efficiently inhaled by the animal. It can ensure that the animal's inhalation amount is guaranteed within a specific time period. At the same time, several ventilation holes can be opened on the mask, or the ratio of air or oxygen in the gas can be ensured to ensure that the animal's normal breathing is not restricted.

[0028] The beneficial technical effects of this invention compared to the prior art are as follows:

[0029] (i) Improve experimental accuracy and have the function of precisely controlling drug exposure conditions: Through the precise control of aerosol generator and air supply device, the consistency of drug dosage and exposure time can be ensured, and the animal can wear a mask, so that the drug components can be delivered to the mask through the trachea and fully inhaled by the animal, greatly reducing experimental errors and making the experimental results accurate and reliable.

[0030] (II) The integrated headband allows for the secure positioning of bioelectrodes in key muscle areas of the animal's head, such as the orbicularis oculi, frontalis, or buccinator muscles. This facilitates the continuous and accurate acquisition of electromyographic (EMG) signal data even during animal activity. This is beneficial for applications in drug toxicity testing, environmental toxicology, and inhalation toxicology, enabling researchers to conduct studies on the effects of toxicity on bio-EMG signals. This acquisition method does not restrict the animal's free movement, preventing strong resistance. The entire process is smooth, orderly, and highly controllable, with continuous, stable, and reliable data acquisition. The secure design also prevents signal termination due to loosening.

[0031] (III) Reasonable data processing ensures high experimental reliability. The application of techniques such as bandpass filters and independent component analysis effectively removes noise, extracts useful electromyographic (EMG) signals, and improves data quality. The mean, variance, and peak value of the EMG signals are calculated, and the spectrogram is analyzed using Fourier transform, providing multi-dimensional data analysis methods. A classifier is trained based on the extracted features, and cross-validation is used to evaluate model performance, ensuring high accuracy even on unseen data. Ultimately, accurate EMG signals exhibiting changes after drug inhalation can be identified and extracted, distinguishing them from conventional EMG signals and achieving reliable processing of the target data signals. Attached Figure Description

[0032] Figure 1 This is a three-dimensional structural view of an inhalation toxicology testing system for animals according to the present invention;

[0033] Figure 2 This is a rear-view perspective view of an inhalation toxicology testing system for animals according to the present invention.

[0034] Figure 3 This is a schematic diagram of the structural composition of an inhalation toxicology experimental system for animals according to the present invention;

[0035] Figure 4 This is a three-dimensional structural view of the exhaust filtration device of an inhalation toxicology experimental system for animals according to the present invention;

[0036] Figure 5 This is a perspective view of the integrated headband structure of the present invention;

[0037] Figure 6 This is a schematic diagram of the mounting structure of the bioelectrode of the present invention;

[0038] Figure 7 This is a schematic diagram of the adjustable connection structure between the secondary headband and the main nose band of the present invention.

[0039] Figure 8 This is a schematic diagram of the installation method of the adjustable tightness of the main nose ring of the present invention;

[0040] Figure 9 This is a schematic diagram illustrating the usage state of the integrated headband of the present invention;

[0041] Figure 10 This is a three-dimensional view of the headband worn and installed in Example 1;

[0042] Figure 11 This is a schematic diagram of the mask structure of the present invention; Figure 12 This is a schematic diagram of the internal structure of the mask of the present invention;

[0043] in:

[0044] 1—Exposure box, 11—Air inlet, 12—Lockable door, 13—Feeding bowl, 14—Transparent observation panel;

[0045] 2—Aerosol generator, 21—Dosage tube, 22—Ultrasonic nebulizer or rotary nebulizer, 23—Dosage dispensing opening;

[0046] 3—Air supply device, 31—Fan, 32—Air supply duct;

[0047] 4—Monitoring module;

[0048] 5—Exhaust air filtration device, 51—Replaceable filter element, 52—Exhaust hood, 53—Exhaust fan.

[0049] 6—Control box;

[0050] 70—Integrated headband, 71—Bioelectrode, 72—Control box, 73—Main nose ring, 74—Secondary head ring, 75—First fastening component, 76—Second fastening component, 77—Elastic component, 78—Wire, 79—Neckband, 80—Face mask. Detailed Implementation

[0051] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0052] Example 1:

[0053] Integrated headband 70: A specially shaped and designed headband that is designed to be comfortably and stably secured to the animal’s head, ensuring that it will not easily slip off or cause discomfort throughout the experiment.

[0054] Bioelectrode 71: The electrode, acting as a sensor, is placed inside the strap. Several electrodes are arranged as needed, and their positions are pre-designed based on the desired data collection site, allowing direct contact with the animal's facial skin. It is used to capture bioelectrical signals within the animal, primarily electromyographic signals from the face. These signals reflect the animal's physiological state and responses.

[0055] Wires 78: Each bioelectrode 2 is connected to the control box 72 via wires 78 integrated in the strap. These wires 78 are responsible for transmitting the bioelectrical signals collected from the electrode and for supplying power to the electrode.

[0056] Control box 72: Located on the strap above the animal's head, it contains: a battery; a data receiving unit responsible for receiving signals from the bioelectrodes 71 via wires 78 and performing preliminary processing; and a wireless communication unit that transmits data wirelessly to the researcher's monitoring terminal, such as a computer or tablet, via Wi-Fi, Bluetooth, or other proprietary wireless technologies. Researchers can remotely monitor and store the animal's electromyographic signal data.

[0057] The main nose ring 73 and secondary head ring 74 are designed as follows: The ring-shaped main nose ring 73 covers the animal's nasal concha and the outer part of its lower jaw, ensuring the device is securely fixed in its base position on the animal's head. The segmented design of the secondary head ring 74 wraps around the animal's ears and connects to the main nose ring 73 at the top and bottom, forming a three-dimensional triangular support structure that effectively distributes pressure and increases stability and comfort when worn. This structural design helps reduce device slippage during animal movement, maintaining the accurate positioning of the bioelectrodes 71.

[0058] Flexibility of the fastening components: The presence of the first and second fastening components, especially the use of Velcro or pin buckles, makes wearing and adjustment simple and quick. These fastening components allow users to easily adjust the tightness of the straps according to the animal's head size, ensuring that it is neither too tight nor too loose, securing the device without causing discomfort to the animal. This design improves the versatility and adaptability of the device.

[0059] Elastic component 77: The use of elastic bands or elastic cloth in specific parts of the main nose ring 73 enhances the adaptability of the strap, allowing it to stretch and contract appropriately with the slight movements of the animal's head, maintaining good electrode fit and ensuring stability and reliability.

[0060] Control box 72 integration and wire 78 layout: The installation position of the control box 72 and the embedded design of the wire 78 optimize the overall layout of the device, avoiding the risk of tangling or damage that may result from exposed wires 78. By integrating the wires 78 inside or on the surface of the strap, not only is the electrical connection protected, but interference with the animal's daily behavior is also reduced, improving safety.

[0061] Location of bioelectrode 71: Bioelectrode 71 is located in key facial muscle areas of the animal, such as the orbicularis oculi, frontalis, or buccinator muscles. Changes in electrical signals in these areas can reflect the animal's physiological state. The choice between dry or gel electrodes depends on experimental needs. Dry electrodes are easier to replace and clean, while gel electrodes provide better skin contact and signal quality, ensuring the accuracy and reliability of data acquisition.

[0062] Preferably, the device also includes a collar 79 as an additional component, which not only provides extra support points for the entire device and distributes the weight, but also increases the stability of the device around the animal's neck. The adjustability of the collar 79 further ensures the fit and safety of the overall device.

[0063] Preferably, the device also includes a mask 80, which is equipped with a ventilation tube. The mask 80 is designed for specific experimental needs, such as controlling gas intake and ensuring consistency of experimental conditions. Its detachability provides flexibility, while the connection of the ventilation tube allows the experimenter to control the composition and amount of gas inhaled by the animal. The reasonable design of the mask 80 also ensures the animal's normal breathing and maintains the animal's safety during the experiment.

[0064] Example 2:

[0065] 1. Preparation before the experiment

[0066] 1.1 Device Inspection and Setup: Confirm that all equipment is connected correctly: Check whether the aerosol generator 2, air supply device 3, monitoring module 4, and exhaust filter device 5 are correctly connected to the monitoring terminal via wires, and confirm that the power supply to each component is stable.

[0067] Install the filter cartridge: Install a new or cleaned filter cartridge in the filter box. In this embodiment, activated carbon or HEPA filter fiber layers are used to ensure clean exhaust.

[0068] Prepare experimental drugs: According to the experimental requirements, add the specified dose of drug through the drug addition opening 23 at the top of the drug tube, and confirm the volume markings on the drug tube wall to ensure accurate drug administration; if dilution with water is required, the dosage solution can be prepared in advance and added directly.

[0069] 1.2 Environmental Setup: Adjusting Oxygen Content and Aerosol Concentration: Ideal exposure environment parameters, such as oxygen content and target aerosol concentration, are preset via the monitoring terminal. The calculation of these parameters is not detailed in this embodiment; typically, the release rate per unit time is calculated based on the nebulizer's spray conversion rate, combined with the blower volume of fan 31 (i.e., the air volume delivered per unit time). This allows for the calculation of the proportion of drug components in the mixed solution. It is necessary to determine the parameters of the hardware equipment at each stage to ensure that the proportion of the final mixed gas output meets experimental requirements. Based on this data and the internal volume of exposure chamber 1, a reasonable proportion of drug components can be calculated and used as a reference standard for the oxygen content sensor and aerosol concentration detector. This allows for monitoring the real-time readings of the oxygen content sensor and aerosol concentration detector. If the readings are below or above these values, an alarm can be issued or the nebulizer operation can be stopped. It should be noted that this part of the calculation and program setting is a conventional technical method. Those skilled in the art can reasonably set the monitoring thresholds based on the corresponding hardware parameters and data, without involving any improvement to the computer program. In this embodiment, the main consideration is the environmental gas formed by the proportion of drug in the gas, and the test animal is placed in this environmental gas for a specific time.

[0070] 2.1 Wearable testing equipment: Ensure that all components, including the integrated headband 70, control box 72, bioelectrode 71, collar 79, mask 80, and ventilation tube, are intact, have sufficient power, and that the wireless communication unit is correctly set up and paired with the monitoring terminal.

[0071] 2.2 Cleaning the animal's face: Gently clean the pig's face with a mild, non-irritating cleanser and a soft cloth, especially the orbicularis oculi, frontalis, and buccinator muscles, to remove grease and dirt so that the electrodes can better contact the skin.

[0072] 3.1 Fitting and Installation; Installing the main nose ring 73: Connect the main nose ring 73 in a loop, slip it over the pig's nose bridge, under the nasal concha, and down to the outside of the lower jaw. Ensure the main nose ring 73 is securely fitted between the pig's nose bridge and lower jaw.

[0073] 3.2 Adjusting the secondary head ring 74: Fix the left and right sections of the secondary head ring 74 to the upper middle of the main nose ring 73, then wrap it around the pig's ears and place it around the base of the ears. Connect it to the lower edge of the main nose ring 73 through the second fastening component 76, such as a buckle with a buckle hole. Adjust the length of the secondary head ring 74 to ensure that it neither compresses the ears nor slips off.

[0074] 3.3 Install the control box 72: Fix the control box 72 in a suitable position on the secondary head ring 74 or the main nose ring 73, ensuring that it does not obstruct the pig's vision or movement and remains stable.

[0075] 3.4 Connecting the bioelectrode 71: The dry or gel bioelectrode 71 is pre-positioned and attached or fixed to the inside of the main nose ring 73 and the secondary head ring 74, aligned with the orbicularis oculi muscle, frontalis muscle, and buccinator muscle area. It is connected to the data receiving unit of the control box 72 through the wire 78 integrated in the strap. Check whether the bioelectrode 71 is in contact with the facial muscles. If necessary, use a patch for assistance.

[0076] 3.5 Use of collar 79 if necessary: ​​Wrap collar 79 around the pig's neck, connect the binding number, and connect collar 79 to the top of the secondary head collar 74 and the bottom of the main nose collar 73. Adjust the tightness to a suitable degree through the third fastening component to help support the entire device.

[0077] 3.6 Install the mask 80. If necessary, the mask 80 is detachably fixed to the main nose ring 73 to ensure that it covers the pig's snout area. When necessary, it is put on the pig's snout area and connected to the main nose ring 73. The mask 80 is connected to the ventilation tube. The other end of the ventilation tube is connected to the gas injection with the set gas flow rate and composition according to the experimental requirements.

[0078] 3.7 Activate the system: Turn on the power to the control box 72, confirm that the data receiving unit and the bioelectrode 71 are successfully connected, and that the wireless communication unit is ready to communicate with the monitoring terminal.

[0079] 4. Animal Placement: Open the lockable door 12 of the exposure chamber 1, gently place the animal to be tested into the chamber, and ensure that the animal is adapted to the environment. Close and lock the door. According to the experimental design, place a food bowl 13 at an appropriate position inside the exposure chamber 1 (10-25cm below the air outlet nozzle) for the animal to use during the experiment, and entice the animal to face the direction of the air inlet 11.

[0080] 5. Experimental Procedure

[0081] 5.1 Start the experiment: Remotely start the aerosol generator 2 through the monitoring terminal. At this time, the ultrasonic nebulizer or rotary nebulizer 22 will start working to convert the drug into fine particle aerosols.

[0082] Simultaneously, the air supply device 3 is activated, and the fan 31 delivers air containing aerosols into the exposure chamber 1 through the air supply duct 32, ensuring uniform distribution of the aerosols. The specific air supply volume is set according to the experimental requirements.

[0083] 5.2 Real-time Monitoring: The monitoring terminal displays oxygen content and aerosol concentration data in real time. If the values ​​deviate from the preset range, the air supply intensity is adjusted or drug input is stopped in a timely manner to maintain the life of the experimental subjects and the stability of experimental conditions. Animal behavioral responses can be observed without interference through the transparent observation panel 14 on the side, and any abnormal behaviors can be recorded. Of course, other experiments can also be conducted on animals that have inhaled drugs. This embodiment will not describe them in detail.

[0084] 5.3 The suction fan 53 operates, driving airflow within the exposure chamber 1. The specific operating power of the suction fan 53 is matched and set according to the air intake volume. Secondly, the drug gas is filtered through an internal filter element to achieve the purpose of discharge. Appropriate filter media is selected based on the drug composition, and timely replacement is ensured.

[0085] 5.4 Data Acquisition: Bioelectrode 71 continuously monitored changes in electrical signals of facial muscles in adult healthy pigs, which represent muscle contraction and relaxation activities.

[0086] 5.5 Data Processing and Transmission: The circuit board built into the control box 72 is responsible for noise reduction, amplification and digitization of the signal. The processed data is transmitted in real time to a remote monitoring computer or other terminal equipment through the wireless communication unit.

[0087] 5.6. Remote monitoring: Researchers viewed and analyzed the received electromyographic signal data in real time on a monitoring terminal to assess the effects of toxic substances on pig muscle activity.

[0088] 5.7. Signal Analysis: The processed electromyographic signals are transmitted to the researchers' monitoring terminal via wireless communication technology. The software analyzes these signals and displays graphical or numerical data of muscle activity, providing intuitive data for assessing toxic effects.

[0089] 6. End of Experiment and Cleanup

[0090] 6.1 Stop the experiment: At the predetermined time or when the experiment ends, stop the aerosol generator 2 and the air supply device 3 through the monitoring terminal, turn off the exhaust filter device 5, and let the aerosol in the exposure box 1 settle naturally for a period of time.

[0091] 6.2 Animal Recovery and Handling: Open door 1 of the exposure chamber, gently remove the animal, and perform appropriate treatment or observation according to subsequent experimental requirements. Record the final oxygen content and aerosol concentration data, experimental time, and the final condition of the animal or other data required for the experiment.

[0092] Clean the inside of exposure chamber 1 to ensure there are no residual drugs or contaminants, in preparation for the next experiment.

[0093] 6.3 Equipment Maintenance: Filter Replacement: Replace the filter elements in the filter box regularly according to usage conditions to maintain the efficient operation of the exhaust system.

[0094] 6.4 Cleaning and Maintenance: Perform necessary cleaning and maintenance on the aerosol generator 2, air supply device 3, etc., to ensure the performance of the device. By following the above steps, this animal inhalation toxicology experimental device can be effectively used to complete scientific experiments while ensuring animal welfare and the safety of experimental personnel.

[0095] Example 3: Experiment and Data Analysis

[0096] Experimental Design 1. Animal Selection: Select healthy adult pigs, approximately 6 months old, weighing between 50-70 kg, ensuring that all animals are of similar sex and weight to reduce the impact of individual differences on the experimental results.

[0097] 2. Grouping: Pigs were randomly divided into a control group and an experimental group, with at least 4 pigs in each group to meet statistical requirements.

[0098] 3. Environmental preparation: Ensure that all pigs are raised in the same environment, including temperature (20-25℃), humidity (50%-60%) and light cycle (12 hours light / 12 hours dark).

[0099] Following the steps in Example 1, the integrated headband 70 is worn on the pig's face, ensuring that several bioelectrodes 71 located on the face area of ​​the band are in direct contact with the skin, and the band is tightened to ensure stability. The bioelectrodes 71 are connected via wires to a control box 72 located on the band above the pig's head. The control box 72 is connected to a data receiving unit via a wireless communication unit, transmitting the collected electromyographic signal data to a monitoring terminal. • Baseline data acquisition:

[0100] Before the experiment began, the pigs were allowed to adapt to wearing the device for one week. During this period, normal electromyographic signals of the pigs were recorded once a day for at least 10 minutes, which served as a baseline reference for subsequent data analysis.

[0101] Experimental phase

[0102] 1. Medication preparation:

[0103] Control group: Pure water was added to aerosol generator 2.

[0104] Experimental group: A certain concentration of drug solution, such as 1 mg / mL, was added to aerosol generator 2.

[0105] Aerosol generation and exposure: Pigs are placed in exposure chamber 1, and the air inlet 11 in exposure chamber 1 is connected to aerosol generator 2 and air supply device 3.

[0106] Start aerosol generator 2 to convert the drug solution into an aerosol, mix it with air, and then inject it into exposure chamber 1. Set the exposure time to 30 minutes and the aerosol concentration to 0.5 mg / m³. 3 .

[0107] Record the aerosol generator's operating time, exposure time, mixed gas concentration, drug dosage, and the start time of animal inhalation.

[0108] Data acquisition: The monitoring terminal can receive and store the real-time electromyographic signals collected by the bioelectrode 71.

[0109] During the experiment, monitoring module 4 monitored the oxygen content and aerosol concentration data in exposure chamber 1 in real time using an oxygen content sensor and an aerosol concentration detector. An alarm was triggered when either the oxygen content or aerosol concentration data exceeded or fell below a set value.

[0110] Phased experiment: The experimental group of animals were exposed to different concentrations or doses of the drug in phases, with sufficient time intervals between each phase to allow for observation and recording of changes in electromyography (EMG) signals. At the end of each phase, EMG signals were recorded repeatedly to increase the reliability and statistical power of the data.

[0111] Signal processing

[0112] Preliminary processing: Use a bandpass filter (e.g., 30-300Hz) to remove noise from the electromyographic signal and retain useful physiological signals.

[0113] Feature extraction: Independent component analysis (ICA) and other signal processing techniques were used to separate components directly related to drug exposure from electromyographic signals.

[0114] Calculate the statistical characteristics of each component, such as mean, variance, and peak value.

[0115] The spectral characteristics of the signal are obtained through Fourier transform, with particular attention paid to the frequency range closely related to nervous system activity.

[0116] Normalization: Normalize all extracted feature values ​​to ensure that data obtained under different experimental conditions are comparable.

[0117] Data Analysis

[0118] Model building: Based on the extracted features, a classifier is trained using machine learning algorithms (such as support vector machines, random forests, etc.) with the aim of identifying the effects of drug exposure on the pig nervous system.

[0119] Model validation: Cross-validation is used to evaluate the model's generalization ability and stability, ensuring the model's predictive accuracy on new data.

[0120] Results Comparison and Interpretation: The electromyographic signal characteristics of the experimental group and the control group were compared and analyzed to explore the specific effects of drug exposure on the function of the pig nervous system, including but not limited to changes in muscle activity patterns and nerve conduction velocity.

[0121] It should be understood that the specific embodiments described above are merely illustrative or explanatory of the principles of the invention and do not constitute a limitation thereof. Therefore, any modifications, equivalent substitutions, improvements, etc., made without departing from the spirit and scope of the invention should be included within the protection scope of the invention. Furthermore, the appended claims are intended to cover all variations and modifications falling within the scope and boundaries of the appended claims, or equivalent forms of such scope and boundaries.

Claims

1. An inhalation toxicology testing system for animals, characterized in that... include: An exposure box (1) is a sealed box structure with a door for placing the animal to be tested. An air inlet (11) is installed at the front end of the box. The air inlet (11) is connected to an aerosol generator (2) and an air supply device (3). Aerosol generator (2) is used to convert liquid or solid drugs into fine particulate mist or aerosol for inhalation by the test animal; it includes a drug delivery tube (21) and an ultrasonic nebulizer or rotary nebulizer (22) connected to the bottom of the drug delivery tube (21), the outlet of the ultrasonic nebulizer or rotary nebulizer (22) being connected to the air inlet (11). An air supply device (3) provides air in a passive or active manner. The air supply device (3) includes a fan (31) and an air supply duct (32), which is connected to the air inlet of the ultrasonic atomizer or rotary atomizer (22). The monitoring module (4), including an oxygen content sensor and an aerosol concentration detector, is installed on the top of the exposure box (1) and connected to the monitoring terminal via wired or wireless communication. The monitoring terminal is used to display the current oxygen content data and aerosol concentration data in the exposure box (1). An exhaust filtration device (5) is installed on the top of the exposure box (1) in a passive or active exhaust manner. It includes a filter, and the gas is discharged to the outside of the exposure box (1) after passing through the filter. An integrated headband (70) is worn on the animal's head. Several bioelectrodes (71) are installed on the inner side of the animal's face area on the band for collecting bioelectrical signals. Each bioelectrode (71) is connected to a control box (72) via a wire (78) integrated on the band. The control box (72) is installed on the strap located above the animal's head. It contains a battery, a data receiving unit, and a wireless communication unit. The data receiving unit is connected to the wire (78), and the wireless communication unit is connected to the data receiving unit. It can transmit the collected data to the monitoring terminal. The monitoring terminal is connected to the aerosol generator (2), the air supply device (3), the exhaust filter device (5), the monitoring module (4), and the control box (72). It can collect and record the data information transmitted by each component and issue monitoring operation commands.

2. The animal inhalation toxicology testing system according to claim 1, characterized in that, The exposure box (1) has a rectangular box-shaped structure. One end is equipped with a lockable door (12), and the other end is equipped with an operation box. The operation box is equipped with the fan (31) and the aerosol generator (2). The fan (31) is connected to the aerosol generator (2) through the air supply pipe (32). The aerosol generator (2) includes a drug tube and an ultrasonic nebulizer or a rotary nebulizer (22). The air inlet (11) is the air outlet nozzle of the ultrasonic nebulizer or the rotary nebulizer (22) and extends directly into the exposure box (1).

3. The animal inhalation toxicology testing system according to claim 1, characterized in that, The oxygen content sensor and aerosol concentration detector are installed in the middle of the top of the exposure box (1). The oxygen content sensor and aerosol concentration detector are connected by a data wire to achieve power supply and data transmission, or data transmission is achieved through a built-in battery via a wireless signal transmission module. The aerosol generator (2), the air supply device (3), and the exhaust filter device (5) are all directly powered by a power supply connected by a wire.

4. The animal inhalation toxicology testing system according to claim 1, characterized in that, The filter includes a replaceable filter element (51), which is installed inside the filter box. The filter box is installed below the exhaust hood (52) and directly connected to the exhaust outlet at the top of the exposure box (1). An exhaust fan (53) is installed above the exhaust hood (52). The exhaust fan (53) is connected to the monitoring terminal via a wire and can draw gas from the exposure box (1). The monitoring terminal is connected to a power source and is connected to various components via wires. It is connected to the monitoring module (4) and can control the start and stop of the aerosol generator (2), the start and stop of the fan (31) of the air supply device (3), and the start and stop of the exhaust filter device (5).

5. The animal inhalation toxicology testing system according to claim 1, characterized in that, The integrated headband (70) includes: The main nose ring (73) can be joined in a ring shape and is used to slip and bind the nasal concha and lower part of the animal's head. The secondary headband (74) is divided into two sections, left and right, with one end of each section fixedly connected to the upper middle part of the main nose ring (73), and the other end wrapping around the ear and connecting to the lower side of the main nose ring (73).

6. The animal inhalation toxicology testing system according to claim 1, characterized in that, The two ends of the main nose ring (73) are provided with first fastening components (75), which can be connected and fixed or opened to facilitate wearing; the other end of the auxiliary head ring (74) is connected to the lower side of the main nose ring (73) through a second fastening component (76). Used to adjust the length of the secondary head ring (74); the first fastening component (75) and the second fastening component (76) may each include Velcro kits at both ends, which are glued together, or a buckle with a pin at one end and several holes arranged on the other end.

7. The animal inhalation toxicology testing system according to claim 1, characterized in that, The control box (72) is installed on the secondary head ring (74), and the wire (78) is embedded in the main nose ring (73) or the secondary head ring (74), or sewn or attached to the surface of the main nose ring (73) or the secondary head ring (74); the bioelectrode (71) is a dry electrode or a gel electrode, and the bioelectrode (71) is located inside the main nose ring (73) or the secondary head ring (74) in the orbicularis oculi muscle, frontalis muscle or buccinator muscle region of the animal's head; The collar (79) is connected to the top of the secondary head collar (74) and the bottom of the main nose collar (73), and has third fastening components at both ends for wearing around the animal's neck.

8. The inhalation toxicology testing system for animals according to claim 1, characterized in that, It also includes a mask (80) which is detachably mounted on the main nose ring (73). The shape and size of the mask (80) can cover the animal's mouth and nose area. The tail end of the mask (80) is connected to a ventilation tube. The ventilation tube is connected to the air supply device or directly connected to the air outlet of the ultrasonic atomizer or rotary atomizer (22).

9. The experimental method based on the inhalation toxicology experimental system according to any one of claims 1-8, characterized in that... Includes the following steps: Step s1: Wear the integrated headband (70) on the animal's face, and make several bioelectrodes (71) on the inner side of the animal's face area directly contact the facial skin, and fix the tightness of the band to make it secure. Step S2: The bioelectrode (71) is connected to the control box (72) on the strap located above the animal's head via a wire. The control box (72) is connected to the data receiving unit via a wireless communication unit and sends the collected electromyographic signal data to the monitoring terminal. Step S3: Add the liquid or solid drug used in the experiment to the aerosol generator (2) in a quantitative amount and ensure that the aerosol generator (2) is in standby mode. Step S4: Place the animal in an exposure box (1), and connect the air inlet (11) in the exposure box (1) to the aerosol generator (2) and the air supply device (3); Step S5: The monitoring terminal can receive and store the real-time electromyographic signals collected by the bioelectrode (71). Step S6: After the aerosol generator (2) is started, it can be converted into fine particulate mist or aerosol. The mist or aerosol containing drug components is mixed with air and injected into the exposure box (1). The running time information of the aerosol generator, the exposure time, the concentration of the mixed gas, the drug dosage information, and the starting time information of animal inhalation are recorded. Step S7: Collect electromyographic signal data detected by the complete bioelectrode (71) during the experiment; and transmit it to the monitoring terminal for analysis and processing; Among them: bioelectrodes (71) are distributed on the orbicularis oculi muscle, frontalis muscle or cheek muscle area of ​​the animal; the monitoring module (4) monitors the oxygen content data and aerosol concentration data in the exposure box (1) in real time through oxygen content sensor and aerosol concentration detector; when the oxygen content data or aerosol concentration data exceeds or falls below the set value, an alarm will be activated.

10. The experimental method according to claim 9, characterized in that... Includes the following steps: A control group and an experimental group were set up to ensure that the two groups were completely identical except for whether they were exposed to toxic substances. The control group did not add any drug components to the aerosol generator (2) and used pure water as a control, while the experimental group added drug components to the aerosol generator (2). Before starting the aerosol generator (2), normal electromyographic signals were collected over a period of time as baseline data for the control group and the experimental group. The experimental group animals were exposed to different concentrations or doses of the drug in stages, with sufficient time intervals between each stage to observe and record changes in electromyography (EMG) signals; at the end of each stage, EMG signals were recorded repeatedly to increase the reliability and statistical power of the data. A bandpass filter is applied to remove noise in the unwanted frequency range, and independent component analysis is used as an advanced signal processing technique to separate the electromyographic signal components related to toxicant exposure. All signal intensities are normalized to the same scale and compared. The mean, variance, and peak value of the electromyographic signal are calculated, and the spectrum of the signal is obtained through Fourier transform to analyze the energy distribution at specific frequencies. Based on the extracted features, a classifier was trained to distinguish between electromyographic signals under normal activity and those under the influence of toxins; cross-validation was used to evaluate the model performance to ensure that it maintains high accuracy on unseen data; the results of the experimental group and the control group were compared to analyze the changing trends of electromyographic signals before and after exposure to toxins.

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