Perioperative period management system and method for mouse short bowel syndrome model

Abstract

The invention discloses a perioperative period management system of a mouse short bowel syndrome model. Comprising a computer module, the computer module is electrically connected with a processing module, the processing module is electrically connected with a data entry module and a medical monitoring module, and the processing module is electrically connected with a prediction model module; the perioperative period management method of the mouse short bowel syndrome model comprises the following steps: S1, selecting a mouse operation experiment, and inputting and monitoring data; s2, obtaining a mouse operation result; s3, mouse state and analysis; according to the method, perioperative period management is optimized, the survival rate of 75% SBR mice is increased, the length and pathological morphology of residual intestines are obviously changed, microbiota is obviously disordered, the life of experimental mice is predicted through the model, the intestinal adaptive change of human SBS can be better simulated, and the survival rate of the mice is increased. And by inputting data information and life monitoring data information, the life of the mouse can be conveniently predicted, and the intestinal tract operation of human SBS can be simulated.

Description

Technical Field

[0001] This invention belongs to the field of short bowel syndrome technology, specifically relating to a perioperative management system and method for a mouse short bowel syndrome model. Background Technology

[0002] Short bowel syndrome (SBS) is a rare malabsorption disorder caused by congenital or acquired factors resulting in the resection or loss of a large portion of the intestine, requiring long-term parenteral nutrition support. The prognosis of SBS patients varies greatly due to differences in etiology, residual small bowel length, and tolerance to parenteral and enteral nutrition. Its low incidence and significant individual variability make clinical studies prone to bias. Mice are ideal animals for simulating SBS due to their high reproductive capacity, low cost, good reproducibility, and genetic similarity to humans. However, mouse models with 50% short bowel resection (SBR) cannot fully mimic the intestinal adaptation and microbial changes seen in human short bowel resection (>75% SBR). The high surgical difficulty and mortality rate of 75% SBR limit its application in current research; furthermore, various perioperative management issues remain with commercially available short bowel syndrome models.

[0003] Existing technologies do not address the issues of setting up various data information for laboratory mice, resulting in inaccurate postoperative life predictions. Furthermore, they do not perform postoperative life monitoring, cannot effectively monitor the specific condition of laboratory mice, cannot analyze abnormal states, and cannot predict the lifespan of laboratory mice. Therefore, we propose a perioperative management system and method for a mouse short bowel syndrome model. Summary of the Invention

[0004] The purpose of this invention is to provide a perioperative management system and method for a mouse short bowel syndrome model, in order to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a perioperative management system for a mouse short bowel syndrome model, comprising a computer module, wherein the computer module is electrically connected to a processing module, the processing module is electrically connected to a data input module and a medical monitoring module, and the processing module is electrically connected to a prediction model module;

[0006] The data entry module is used to input various data information of the experimental mice, which facilitates the prediction of the mice's condition and subsequent lifespan, thereby improving the prediction accuracy of the prediction model module. The medical monitoring module is used to monitor the experimental mice in real time after surgery, detecting various vital signs of the mice, which allows the prediction model module to obtain the mice's vital signs in real time. The prediction model module is used to calculate the vital signs of the experimental mice and predict their lifespan by using the input and monitored data. The monitoring indicators of the data entry module and the medical monitoring module include body weight, food intake, ambient temperature, remaining jejunum, ileum length, and fecal 16S rDNA sequencing. Fecal 16S rDNA sequencing is used to determine the intestinal flora.

[0007] The prediction model module uses Kaplan-Meier survival probability estimation, as shown in the following formula:

[0008]

[0009] The survival rate formula for the Kaplan-Meier survival curve is as follows: survival probability S(t) i The probability of survival at the previous time point i-1 is equal to the probability of survival multiplied by 1 and d. i / n i The product of the differences, n i It is t i Total number of survivors before point d i The event is in t i Number of occurrences, t i Let S(t) represent the i-th time point. i -1) represents the survival probability at the previous time point i-1;

[0010] The prediction model module may employ the Cox proportional hazards regression model. The Cox model is a semi-parametric model because its formula includes both parametric and non-parametric components. The parameters of a parametric model are finite-dimensional, meaning a finite number of parameters represents the model distribution. In contrast, the parameters of a non-parametric model belong to an infinite-dimensional space and cannot be represented by a finite number of parameters. The Cox model formula is as follows:

[0011] h(t)=h0(t)×exp(b1x1+b2x2+…+b p x p ),

[0012] Where t is the survival time, from x1, x2 to x... p This refers to multiple variables with predictive effects, b1, b2 to b pThis refers to the effect size, or effect size, for each variable, which can be understood as the degree of influence of the outcome. h(t) represents the hazard at different times t, i.e., the risk value, while h0(t) is the baseline hazard function, meaning that the hazard is determined by the other covariates x1, x2, ..., x... p When all values ​​are 0, i.e. when it has no effect, it is a function that measures risk.

[0013] Preferably, the computer module is electrically connected to an adapter module, which includes a step-down circuit, a voltage regulator circuit, a filter circuit, a rectifier circuit, and a surge protection circuit. The step-down circuit reduces the voltage, the rectifier circuit converts AC voltage to DC voltage, the filter circuit filters out AC voltage from the DC voltage, the voltage regulator circuit stabilizes the supply voltage, and the surge protection circuit prevents voltage surges from damaging subsequent electronic equipment.

[0014] Preferably, the computer module is electrically connected to a display module and a keyboard and mouse module. The display module is used to display the system's data information and predicted images, and the keyboard and mouse module is used to effectively control and adjust the system, and facilitate the input of various parameter information of the experimental mice.

[0015] Preferably, the processing module is electrically connected to a communication module, which is used to transmit the calculation data information of the prediction model module and the monitoring data information of the medical monitoring module, so that doctors can obtain them in a timely manner. The communication module is connected to a mobile device.

[0016] Preferably, the computer module is electrically connected to an auxiliary module, which includes a status indicator light, an alarm, and a memory. The status indicator light is used to display the operating status of the system, the alarm is used to warn of system abnormalities, and the memory is used to store data information.

[0017] Preferably, the status indicator lights include a power supply indicator light, a fault indicator light, a communication indicator light, and a running indicator light. The alarm device is an audible and visual alarm. The memory includes a ROM memory, a RAM memory, and a cache memory. The ROM memory is used to store the system running program and algorithm, and the RAM memory is used to store data information and running logs.

[0018] Preferably, the processing module includes an acquisition unit for receiving data information, a filtering unit for filtering out noise from the data information, a conversion unit for performing analog-to-digital conversion on the data information, and a gain unit for amplifying the data information.

[0019] Preferably, the filtering unit employs a low-pass filter, which is a first-order filter, also known as a first-order inertial filter or a first-order low-pass filter.

[0020] The algorithm formula for the first-order low-pass filter is as follows:

[0021] Y(n) = αX(n) + (1-α)Y(n-1),

[0022] In the formula: α = filter coefficient; X(n) = current sample value; Y(n-1) = previous filter output value; Y(n) = current filter output value. The first-order low-pass filtering method uses the current sample value and the previous filter output value to weight the effective filter value, so that the output has a feedback effect on the input.

[0023] Preferably, the data entry module needs to enter data including preoperative body weight, intraoperative surgical procedures, postoperative dietary strategies and environmental temperature settings. The intraoperative surgical procedures include bowel resection length, anastomosis location and removal of bowel contents.

[0024] The medical monitoring module includes vital sign monitoring, drug monitoring, drug abnormality monitoring, and drug use time monitoring. The vital sign monitoring includes blood pressure detection, heart rate monitoring, and respiration monitoring.

[0025] The perioperative management method for a mouse short bowel syndrome model includes the following steps:

[0026] S1. C57BL / 6J mice were selected. Perioperative management was optimized by controlling preoperative body weight, intraoperative surgical procedures, postoperative dietary strategies, and environmental temperature settings. Approximately 75% of the small intestine was removed, starting from 2 cm from the Treitz ligament and ending at 5-6 cm from the ileocecal junction. The contents of the small intestine were flushed before intestinal anastomosis. The mice were divided into 20-25g and 25-30g groups according to their preoperative weight. Postoperatively, the mice were divided into six groups according to their feeding restrictions (gradually increasing food intake) and non-restricted feeding, and environmental temperatures of 25°C and 30°C. The mice were followed up for 14 days postoperatively. The survival rates of SBS mice with body weights of 20-25g and 25-30g, feeding restrictions and non-restricted feeding, and environmental temperatures of 25°C and 30°C were compared. The length of the residual small intestine was measured. Hematoxylin-eosin staining and immunofluorescence were used to detect pathological changes in the residual intestine. Western blot was used to detect the expression of intestinal barrier-related proteins. 16S rDNA sequencing was used to study the changes in the intestinal microbiota of SBS mice.

[0027] S2. Results: With postoperative day 14 as the observation endpoint, the survival rate of SBS mice in the 25-30g group was significantly higher than that in the 20-25g group (81.3% vs. 43.5%, p = 0.017). Postoperative food restriction significantly improved the survival rate, with the survival rate of the non-restricted food group being 20.0% and the restricted food group being 81.3% (p = 0.004). The mortality rate of mice reached 75% two days after surgery at 25℃, while all mice in the 30℃ group survived.

[0028] S3. By 14 days post-surgery, the remaining jejunum and ileum lengths of SBS mice increased by 1.7-fold and 1.4-fold, respectively; villus heights of the jejunum and ileum increased by 1.5-fold and 1.4-fold, respectively; and crypt depths increased by 1.3-fold and 2.0-fold, respectively. Compared with the sham-operated group, the SBS group showed increased expression of Villin and Occludin. PCNA expression decreased significantly one week post-surgery, but increased over time. 16S rDNA sequencing analysis of feces from the ileocecal junction showed that 75% of SBR mice had dysbiosis, with low species diversity and richness. The relative abundance of Proteobacteria was increased, while the relative abundance of Bacteroidetes, Actinobacteria, and Cyanobacteria was decreased.

[0029] Compared with the prior art, the beneficial effects of the present invention are:

[0030] This invention optimizes perioperative management, including preoperative body weight, selection of intestinal resection location and preoperative cleaning of intestinal contents before intestinal anastomosis, postoperative dietary strategy adjustment and appropriate environmental temperature, which can significantly improve the survival rate of 75% of SBR mice. Within 2 weeks after intestinal resection, the length and pathological morphology of the residual intestine changed significantly, and the microbiota was significantly disordered. Furthermore, the model can predict the life of experimental mice and better simulate the intestinal adaptation changes in human SBS, reflecting the intestinal adaptation pathophysiological characteristics after the formation of short bowel syndrome. It can serve as an ideal animal model for short bowel syndrome. By recording data and monitoring vital signs, it is easy to predict the life of mice and realize intestinal surgery that simulates human SBS. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the system structure of the present invention;

[0032] Figure 2 This is a schematic diagram of the steps of the present invention. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] Please see Figures 1-2 The present invention provides a technical solution: a perioperative management system for a mouse short bowel syndrome model, comprising a computer module, wherein the computer module is electrically connected to a processing module, the processing module is electrically connected to a data input module and a medical monitoring module, and the processing module is electrically connected to a prediction model module;

[0035] The data entry module is used to input various data information of the experimental mice, which facilitates the prediction of the mice's condition and subsequent lifespan, thereby improving the prediction accuracy of the prediction model module. The medical monitoring module is used to monitor the experimental mice in real time after surgery, detecting various vital signs of the mice, which allows the prediction model module to obtain the mice's vital signs in real time. The prediction model module is used to calculate the vital signs of the experimental mice and predict their lifespan by using the input and monitored data. The monitoring indicators of the data entry module and the medical monitoring module include body weight, food intake, ambient temperature, remaining jejunum, ileum length, and fecal 16S rDNA sequencing. Fecal 16S rDNA sequencing is used to determine the intestinal flora.

[0036] The prediction model module uses Kaplan-Meier survival probability estimation, as shown in the following formula:

[0037]

[0038] The survival rate formula for the Kaplan-Meier survival curve is as follows: survival probability S(t) i The probability of survival at the previous time point i-1 is equal to the probability of survival multiplied by 1 and d. i / n i The product of the differences, n i It is t i Total number of survivors before point d i The event is in t i Number of occurrences, t i Let S(t) represent the i-th time point. i -1) represents the survival probability at the previous time point i-1;

[0039] The prediction model module may employ the Cox proportional hazards regression model. The Cox model is a semi-parametric model because its formula includes both parametric and non-parametric components. The parameters of a parametric model are finite-dimensional, meaning a finite number of parameters represents the model distribution. In contrast, the parameters of a non-parametric model belong to an infinite-dimensional space and cannot be represented by a finite number of parameters. The Cox model formula is as follows:

[0040] h(t)=h0(t)×exp(b1x1+b2x2+…+b p x p ),

[0041] Where t is the survival time, from x1, x2 to x... p This refers to multiple variables with predictive effects, b1, b2 to b p This refers to the effect size, or effect size, for each variable, which can be understood as the degree of influence of the outcome. h(t) represents the hazard at different times t, i.e., the risk value, while h0(t) is the baseline hazard function, meaning that the hazard is determined by the other covariates x1, x2, ..., x... p When all values ​​are 0, i.e. when it has no effect, it is a function that measures risk.

[0042] To ensure effective power supply to the computer module and maintain the safety of the electronic equipment, in this embodiment, preferably, the computer module is electrically connected to an adapter module. The adapter module includes a step-down circuit, a voltage regulator circuit, a filter circuit, a rectifier circuit, and a surge protection circuit. The step-down circuit reduces the voltage, the rectifier circuit converts AC voltage to DC voltage, the filter circuit filters out AC voltage from the DC voltage, the voltage regulator circuit stabilizes the power supply voltage, and the surge protection circuit prevents voltage surges from damaging subsequent electronic equipment.

[0043] In order to better control the system, facilitate the input of parameter information, and display the parameter information and images, in this embodiment, preferably, the computer module is electrically connected to a display module and a keyboard and mouse module. The display module is used to display the system's data information and predicted images, and the keyboard and mouse module is used to effectively control and adjust the system, and facilitate the input of various parameter information of the experimental mice.

[0044] In order to enable data transmission and facilitate remote communication, in this embodiment, preferably, the processing module is electrically connected to a communication module. The communication module is used to transmit the calculation data of the prediction model module and the monitoring data of the medical monitoring module, so that doctors can obtain them in a timely manner. The communication module is connected to a mobile device.

[0045] To enable auxiliary operations on the system and improve its performance, in this embodiment, preferably, the computer module is electrically connected to an auxiliary module. The auxiliary module includes a status indicator light, an alarm, and a memory. The status indicator light displays the operating status of the system, the alarm alerts system abnormalities, and the memory stores data.

[0046] To display the system status and issue alarms, and to improve the storage and retrieval of data information, in this embodiment, preferably, the status indicator lights include a power supply indicator light, a fault indicator light, a communication indicator light, and a running indicator light; the alarm device is an audible and visual alarm; and the memory includes a ROM memory, a RAM memory, and a cache memory. The ROM memory is used to store the system's running program and algorithms, and the RAM memory is used to store data information and running logs.

[0047] In order to achieve effective transmission and processing of data information and improve the accuracy and security of data information, in this embodiment, preferably, the processing module includes an acquisition unit for receiving data information, a filtering unit for filtering out noise from the data information, a conversion unit for performing analog-to-digital conversion on the data information, and a gain unit for amplifying the data information.

[0048] To filter the data and remove noise, in this embodiment, preferably, the filtering unit uses a low-pass filter, specifically a first-order filter, also known as a first-order inertial filter or a first-order low-pass filter.

[0049] The algorithm formula for the first-order low-pass filter is as follows:

[0050] Y(n) = αX(n) + (1-α)Y(n-1),

[0051] In the formula: α = filter coefficient; X(n) = current sample value; Y(n-1) = previous filter output value; Y(n) = current filter output value. The first-order low-pass filtering method uses the current sample value and the previous filter output value to weight the effective filter value, so that the output has a feedback effect on the input.

[0052] In order to enable the input of different factors and to monitor the postoperative status of experimental mice, in this embodiment, preferably, the data input module needs to input the following data information: preoperative body weight, intraoperative surgical procedures, postoperative dietary strategy and environmental temperature settings. The intraoperative surgical procedures include intestinal resection length, anastomosis location and cleaning of intestinal contents.

[0053] The medical monitoring module includes vital sign monitoring, drug monitoring, drug abnormality monitoring, and drug use time monitoring. The vital sign monitoring includes blood pressure detection, heart rate monitoring, and respiration monitoring.

[0054] Working principle and usage process of this invention:

[0055] The first step involved using C57BL / 6J mice to optimize perioperative management, including preoperative body weight, intraoperative surgical procedures, postoperative dietary strategies, and environmental temperature settings. Data was entered via a keyboard and mouse module. Surgery then commenced, removing approximately 75% of the small intestine from 2 cm below the Treitz ligament to 5-6 cm below the ileocecal junction. The small intestine contents were flushed before anastomosis. Postoperatively, the mice were grouped and their vital signs were monitored using a medical monitoring module. Mice were divided into six groups based on their preoperative weight: a 20-25g group and a 25-30g group. Postoperatively, they were further divided into groups based on their feeding restrictions (gradually increasing food intake) and their environmental temperatures (25°C and 30°C). The mice were followed up for 14 days post-surgery. The survival rates of SBS mice were compared between 20-25g and 25-30g mice, between those with restricted and unrestricted feeding, and between those with environmental temperatures of 25°C and 30°C. The length of the residual small intestine was measured. Hematoxylin-eosin staining and immunofluorescence were used to detect pathological changes in the residual intestine. Western blot was used to detect the expression of intestinal barrier-related proteins. 16S rDNA sequencing was used to study changes in the gut microbiota of SBS mice. The entered data and data from the medical monitoring module were then used in a prediction model module to predict the lifespan of the mice, facilitating the simulation of SBS-like intestinal surgeries.

[0056] The second step, results, with postoperative day 14 as the observation endpoint, showed that the survival rate of SBS mice in the 25-30g group was significantly higher than that in the 20-25g group, i.e., 81.3% vs. 43.5%, p = 0.017; postoperative food restriction significantly improved the survival rate, i.e., the survival rate of the unrestricted food group was 20.0%, while that of the restricted food group was 81.3%, p = 0.004; the mortality rate of mice reached 75% 2 days after surgery at 25℃, while all mice in the 30℃ group survived;

[0057] Thirdly, by 14 days post-surgery, the remaining jejunum and ileum lengths of SBS mice increased by 1.7 times and 1.4 times, respectively; villus heights of the jejunum and ileum increased by 1.5 times and 1.4 times, respectively; and crypt depths increased by 1.3 times and 2.0 times, respectively. Compared with the sham-operated group, the SBS group showed increased expression of Villin and Occludin, and a significant decrease in PCNA expression one week post-surgery, but an increase over time. 16S rDNA sequencing analysis of fecal samples from the ileocecal region showed that 75% of SBR mice exhibited dysbiosis, with low species diversity and richness. The relative abundance of Proteobacteria was increased, while the relative abundance of Bacteroidetes, Actinobacteria, and Cyanobacteria was decreased. The data was then transmitted to a mobile device via a communication module for easy access and viewing by physicians.

[0058] This study aimed to overcome the high postoperative mortality rate in 75% SBR mice by optimizing perioperative management, including preoperative body weight selection, intraoperative surgical strategy optimization, and postoperative dietary and environmental temperature adjustments. Based on this, the study evaluated changes in residual intestinal morphology and function and intestinal flora dysbiosis two weeks postoperatively, hoping to establish a more stable mouse model that is closer to human SBR.

[0059] Materials and Methods

[0060] C57BL / 6J mice were weighed daily before surgery and fed standard diets, with a 12-12h light-dark cycle.

[0061] Preoperative mouse weight selection

[0062] Mice were divided into two groups according to their body weight: the observation group (25-30g) and the control group (20-25g).

[0063] Optimize surgical methods

[0064] Mice were fasted for 8 hours prior to surgery. During the operation, experimental mice underwent jejunoileal resection, while control mice underwent sham abdominal incision. Under 2% isoflurane anesthesia, a 1cm longitudinal incision was made in the abdominal cavity. The entire small intestine was pulled out of the abdominal cavity with cotton swabs to reduce the need to clamp the intestinal segment and avoid damage to the intestinal wall. The small intestine resection began 2cm from the ligament of Treitz and ended 5-6cm from the ileocecal junction, removing approximately 75% of the small intestine. The first-order mesenteric vascular arch was ligated with 9-0 monofilament sutures, and the third-order mesenteric microvessels were electrocoagulated to prevent bleeding. Approximately 20cm of the small intestine was removed with microsurgical scissors. The remaining intestinal contents were flushed with a 5ml syringe to prevent postoperative obstruction due to food residue. End-to-end single-layer interrupted anastomosis was performed using 10-0 monofilament sutures to restore intestinal continuity. The abdominal wall muscle layer and skin were sutured with 4-0 silk sutures. Immediately after surgery, administer 5 mg / kg of carboprofen and 1 ml of glucose sodium chloride injection (5% glucose and 0.9% sodium chloride) subcutaneously. Starting from the second day after surgery, administer 1 ml of glucose sodium chloride injection subcutaneously daily for 6 days.

[0065] 3. Postoperative dietary strategy

[0066] Compare the effects of different postoperative feeding methods on survival rate.

[0067] Restricted feeding: Oral rehydration salts for 1-2 days post-surgery, 0.5g / day of solid feed for 3-4 days, 1g / day for 5-6 days, 2g / day for 7-8 days, and no feeding restriction for 9-14 days.

[0068] Non-restrictive diet: oral rehydration salts are given only on the first day after surgery, and a full liquid diet is given from the second day onwards.

[0069] 4. Ambient temperature setting

[0070] After the surgery, SBS mice were placed in a normal room temperature environment and a heated pad environment, respectively. The normal room temperature was 25 degrees Celsius, and the heated pad was placed in the 1 / 2 cage area with the temperature set to 30 degrees Celsius.

[0071] 5. Intestinal adaptation and flora detection

[0072] 5.1 Length and pathological changes of the remaining intestinal segment

[0073] Two weeks post-surgery, mice with 75% SBR were sacrificed, and intestinal length was measured. The jejunum proximal to the anastomosis and the ileum distal to the anastomosis were harvested, fixed in 10% formalin, embedded in paraffin, and prepared for use. Hematoxylin and eosin staining was used to assess intestinal structure, and images were taken with an OLYMPUS BX51 microscope to measure villus height and crypt depth in the jejunum and ileum.

[0074] 5.2 Detection of intestinal barrier-related proteins

[0075] Intestinal segments were blocked in 3% bovine serum albumin and 0.03% Triton-X100 at room temperature for 30 min, and then incubated overnight at 4°C with primary antibodies (occludin and villin). Secondary antibodies (anti-mouse or anti-rabbit) were incubated at room temperature for 1 hour, followed by nuclear DAPI staining. Immunofluorescence was used to detect the expression of occludin and villin proteins on the surface of intestinal epithelial cells 14 days after 75% intestinal resection.

[0076] Western blot was used to detect the expression of occludin, proliferation-associated protein (PCNA), and villin in the intestinal tract at 7 and 14 days post-surgery.

[0077] 5.3 Intestinal flora detection

[0078] Fecal samples were collected from the ileocecal region 14 days post-surgery, and total genomic DNA was isolated using a DNA extraction kit. PCR products were collected and sequenced using the Illumina MiSeq platform (Illumina, San Diego, CA, USA). High-quality reads were clustered into operational taxonomic units (OTUs) based on sequences with ≥97% similarity and analyzed using the QIIME2 platform.

[0079] 6. Statistical Analysis

[0080] Statistical analysis was performed using GraphPad-Prism 6 software (CA, USA). t-tests were used to compare continuous variables between two groups. Chi-square tests were used to compare survival differences between groups. Analysis of variance was used for multivariate comparisons, with Tukey's multiple comparison method used for post-hoc tests. Overall survival was calculated using the Kaplan-Meier method, and the log rank test was used to compare survival rates. A p-value less than 0.05 was considered statistically significant.

[0081] result

[0082] I. Survival Rate

[0083] 1. The high preoperative body weight group had a higher postoperative survival rate.

[0084] The final observation point was 14 days after modeling. The survival rate of the 20-25g group (low body weight group) was 43.5% (13 / 23), and the survival rate of the 25-30g group (high body weight group) was 81.3% (13 / 16).

[0085] Causes of death included intestinal obstruction (8 cases in the low body weight group and 1 case in the high body weight group), anastomotic leakage (3 cases in the low body weight group) and diarrhea (2 cases in each group). The obstruction was mostly located at the anastomosis.

[0086] 2. Postoperative dietary restrictions improve survival rates

[0087] On postoperative day 1, all mice were given oral rehydration salts and remained in normal condition. From day 2 onwards, mice in the non-restricted feeding group exhibited upper abdominal distension and poor responsiveness. Between 2 and 4 days post-surgery, the mortality rate in the non-restricted feeding group was 80% (8 / 10), while there were no deaths in the restricted feeding group. Autopsy revealed that the primary cause of death in the non-restricted feeding group was anastomotic obstruction (6 cases), with the entire liquid diet gradually solidifying and obstructing the intestine, resulting in significant dilation of the proximal intestinal segment near the anastomosis. A few cases involved obstruction below the anastomosis (1 case), followed by anastomotic leakage (1 case).

[0088] 3. An ambient temperature of 30℃ improves the postoperative survival rate of mice.

[0089] Animal housing temperatures are typically set at 20-25℃. Mice are prone to decreased activity and hypothermia two days after surgery. On the second day post-surgery, 75% (3 / 4) of mice died from hypothermia at normal room temperature, but all survived after the ambient temperature was raised to 30℃. In preliminary experiments, mice were observed to prefer a warm environment of 30℃ post-surgery when a heating pad was placed in the housing. When the heating pad temperature was set to 35℃, the mice moved away from it.

[0090] II. Postoperative weight changes

[0091] The body weight of mice in both the SBS group and the sham-operated group continued to decrease from day 1 to 4 post-surgery. From day 5 to 7 post-surgery, as food intake was gradually increased, the rate of body weight loss slowed in both groups. From day 8 to 14 post-surgery, the body weight of mice in the SBS group did not continue to decrease, while the body weight of mice in the sham-operated group gradually increased (P<0.05).

[0092] III. Adaptive Pathological Changes in the Intestine

[0093] Fourteen days after 75% bowel resection, the jejunum and ileum lengthened by 1.7-fold and 1.4-fold, respectively, while there was no statistically significant difference in colon length. The jejunal villus height in the SBS group and the sham group were (845.3±21.3) μm and (574.9±29.1) μm, respectively, and the ileal villus height were (378.6±13.0) μm and (273.4±10.5) μm, respectively (p<0.05). The jejunal and ileal crypt depths were (149.6±8.2) μm and (112.4±4.0) μm, and (179.7±6.7) μm and (91.1±3.1) μm, respectively (p<0.05). The villus height of the jejunum and ileum increased by 1.5-fold and 1.4-fold, respectively, and the crypt depth increased by 1.3-fold and 2.0-fold, respectively.

[0094] IV. Intestinal Mucosal Barrier

[0095] Immunofluorescence revealed increased expression of occludin and villilin in the ileal epithelial cells of SBS mice, and the increased expression of occludin and villilin was associated with prolonged postoperative time. PCNA expression was significantly reduced at 1 week postoperatively, and increased with time after 2 weeks.

[0096] V. Intestinal flora analysis

[0097] At the phylum level, the presence of Proteobacteria increased and Firmicutes decreased after the formation of SBS. At the genus level, Escherichia-Shigella, Bacteroides, and Helicobacter were abundant in the SBS group, while Muribauculaceae was predominant in the control group. Analysis using Chao1, observed species, Shannon, and Simpson indices showed a significant decrease in alpha diversity in the SBS group (p<0.001). Principal component analysis (PCA) and principal coordinate analysis (PCoA) showed beta diversity of 15.14% and 57.59% for PC1 and 12.59% and 17.97% for PC2, respectively, indicating a difference in gut microbiota composition between the SBS and control groups. LEfSe analysis of fecal microbiota in both groups revealed abundant Enterobacterales, Enterobacteriaceae, Proteobacteria, Escherichia-Shigella, and Gammaproterpbacteria in the fecal samples of the SBS group. The bacteria with the highest abundance in the control group were Muribauculaceae and Bacteroidia.

[0098] discuss

[0099] Intestinal underadaptation is a major cause of most complications in Short Bowel Syndrome (SBS) and intestinal transplantation. Many challenges remain in its treatment, including recurrent severe dehydration, catheter-related infections, intestinal failure, and liver disease associated with intestinal failure. The ultimate goal of SBS is intestinal autonomy, and intestinal adaptation is related to the etiology of SBS, the length and anatomical type of the remaining intestine, the presence of hematogenous infection, and related complications. Research on intestinal adaptation mechanisms requires intestinal tissue samples from different time points and sites, but clinical sample sizes are limited, making multi-site sampling difficult. Intestinal microbiota studies are easily affected by varying clinical conditions and medications, failing to meet these requirements. Animal models can simulate different types of short bowel syndrome based on the extent of intestinal resection and can analyze intestinal adaptation status and changes in gut microbiota at different time points after SBS surgery. Animal models not only readily provide sufficient sample sizes but also allow for rigorous experimental conditions and the acquisition of tissue specimens to understand the entire development process of SBS.

[0100] A search of the PubMed database from January 1, 2013 to January 1, 2023, using the keywords "short bowel syndrome" and "animal model," yielded 178 articles over a 10-year period. After reviewing articles on the use of animal models of short bowel syndrome (SBS), a final selection of 98 articles on SBS model construction was made, including 5 on zebrafish (5.1%), 16 on mice (16.3%), 41 on rats (41.8%), and 36 on piglets (36.7%). Most studies chose rats and piglets primarily because these animals are easier to resect and anastomose, but their genetic homology is much lower than that of mice, and there are limitations to using germ-free individuals for gut microbiota and metabolic studies. Mice have higher reproductive rates, lower feeding costs, better reproducibility, and their intestinal anatomy and major phyla are similar to humans. Furthermore, germ-free mice have been used more extensively in gut microbiota research. Therefore, a well-developed mouse SBS model can provide better technical support for human SBS research.

[0101] In 1996, Helmrath first reported experimental data on mouse SBS, demonstrating that resection of 50% of the small intestine was feasible (85% survival rate). Increasing the resection to 75% resulted in a survival rate of only 16%. Over the past decade, mouse SBS models have mostly used a 50% small bowel resection (SBR), i.e., from 1-2 cm distal to the ligament of Treitz to 12 cm proximal to the ileocecal junction, or from 5-8 cm distal to the ligament of Treitz to 7-10 cm proximal to the ileocecal junction. A 40% small bowel resection, i.e., resection of 12 cm of the ileum and cecum, has also been used.

[0102] Generally, human small bowel syndrome (SBS) is defined as a loss of >75% of small bowel length, which differs significantly from current mouse SBS models. A 50% or 40% small bowel bypass (SBR) does not fully mimic the anatomical and physiological conditions of a 75% human SBR. A 50% SBR neither induces intestinal dysfunction nor alters gut microbiota diversity. Due to its high mortality rate, detailed reports on intestinal function changes in a 75% SBR have not been available.

[0103] In establishing a small bowel resection (SBS) model with 75% small bowel removed, survival was improved by optimizing surgery and perioperative care, and the proportion of small bowel removed more closely approximated the length of intestinal loss in human SBS. Compensatory growth of the remaining small bowel and alterations in the gut microbiota better simulated the functional units of the human SBS gut, crypt and villus morphology, changes in cell signaling, and alterations in the gut microbiota.

[0104] The survival rate of mice was significantly related to their preoperative surgical weight. 8-14 week old mice (weighing 22-30g) were typically used for 40-50% SRB. Survival curves were plotted based on mortality rates of mice with different weights in this study: the mortality rate was higher in the 20-25g group than in the 25-30g group. The 14-day survival rate was 81.3% in the 25-30g group and 43.5% in the 20-25g group. Compared to 20-25g mice, 25-30g mice showed greater tolerance to diarrhea and postoperative obstruction. Low-weight mice were less able to tolerate continued weight loss and were more prone to anastomotic obstruction and anastomotic leakage.

[0105] The biggest challenge in improving the survival rate of SBS mice is reducing anastomotic obstruction. This study found that obstruction is mostly located at the anastomosis, and distal anastomosis can also cause intestinal obstruction. In both the previous 50% SBR and the 75% SBR model used in this study, the anastomosis was close to the proximal jejunum (2-3 cm from the ligament of Treitz). This allowed food to pass through the anastomosis quickly after entering the stomach, preventing the formation of large chyme and reducing the risk of proximal anastomotic obstruction. The 50% SBR model retained 12 cm of distal small intestine. In contrast, the 75% SBR mice retained only 5-6 cm of distal small intestine, which reduced the risk of distal intestinal obstruction. Flushing the contents of both proximal and distal intestinal segments with a syringe equipped with a gavage needle before intestinal anastomosis was also to avoid postoperative obstruction caused by intestinal contents blocking the intestine before intestinal function had recovered.

[0106] Sommovilla et al. suggested that feeding standard rodent diets for one week post-surgery increases intestinal obstruction and mortality. This study found that even with oral rehydration salts administered 24 hours post-surgery, followed by a full-volume liquid diet, intestinal obstruction could still occur. Although a liquid diet leaves no residue, the liquid food can solidify into chyme under the influence of gastric acid, blocking the anastomosis or intestinal lumen. Conversely, even with a standard diet and restricted feeding post-surgery, the reduced food intake allows chyme to pass more easily through the anastomosis without accumulating at the site, increasing the survival rate to 81.4%.

[0107] The optimal temperature range for the barrier environment index in mice is 20-26°C. Mice undergoing 50% bowel resection can be incubated overnight in a 31°C air-shielded isolation incubator. This study found that 48 hours after surgery, mice exhibited decreased activity accompanied by hypothermia. Without rewarming, 75% of the mice died. When the heating pad temperature was set to 30°C, mice were more inclined to congregate on the heating pad rather than in the unheated area of ​​the cage (room temperature 25°C). When the heating pad temperature was increased to 35°C, the mice moved away from the heat source. Therefore, a suitable postoperative environmental temperature is one of the key factors for improving the survival rate of mice undergoing 75% bowel resection.

[0108] A mouse model with 75% intestinal resection mimics the structural and functional changes in the human SBS gut.

[0109] Intestinal adaptation is a natural compensatory process that begins after extensive bowel resection. It involves structural and functional changes in the remaining intestine.

[0110] Patients with short bowel syndrome (SBS) experience intestinal morphological changes after bowel resection, including increased villus height, increased crypt depth, intestinal cell proliferation, and luminal dilation. In this study's SBS model with 75% SBR, significant changes in intestinal morphology were also observed, with elongation of the remaining jejunum and ileum, and a significant increase in crypt depth and villus height. The increased absorptive surface area of ​​the remaining intestine gradually compensates for the lost intestinal segments, thereby increasing the nutrient absorption capacity of the remaining intestine.

[0111] Microscopically, intestinal barrier markers occludin and villin gradually increased at 7 and 14 days post-surgery, suggesting that intestinal adaptation gradually improves with prolonged postoperative time, consistent with the progression of intestinal adaptation in human SBS. Seven days after intestinal resection, the expression of proliferating cell nuclear antigen (PCNA) in the intestine decreased, but increased with prolonged survival at 14 days post-surgery. Sueyoshi et al. found that in mice receiving 50% SBR, PCNA-positive cells in the intestinal crypts were nearly normal at 7 days post-surgery, but significantly increased at 90 days post-surgery. Compared to 50% SBR, 75% SBR resulted in impaired intestinal epithelial cell proliferation, making it more suitable for studying intestinal adaptation in human SBS.

[0112] Of course, the interaction between microbes and the host, and the genes expressed by microbes, may contribute to the adaptation of intestinal structure. SBS often presents with intestinal dysbiosis and small intestinal bacterial overgrowth, which can easily lead to recurrent bloodstream infections, failure of parenteral nutrition withdrawal, liver failure, and metabolic bone disease. Compared with well-developed SBS children, malnourished SBS children have a deficiency of Firmicutes and an increase of pro-inflammatory Enterobacteriaceae. Overall bacterial diversity is reduced in both adult and pediatric SBS patients. The length of the remaining intestine affects changes in the intestinal microbiome; in SBS children with a small intestine length <35 cm, the relative abundance of Proteobacteria is increased, while the microbial structure of the remaining small intestine >35 cm is not significantly different from the control group. However, in 50% SBR mice with preserved ileocecal region, after a period of intestinal adaptation, body weight increased, but intestinal microbial diversity remained unchanged. When SBR reached 75%, the mice exhibited dysbiosis, with an increased relative abundance of Proteobacteria associated with increased mucosal inflammation 14 days post-surgery, while beneficial microbiota was significantly reduced, and both species diversity and richness were low. The changes in gut microbiota in 75% of SBRs 14 days post-surgery reflect, to some extent, gut microbiota dysbiosis in human short bowel syndrome.

[0113] The remaining intestinal length affects the gut microbiota structure, and its intestinal adaptation also changes at the molecular level. Therefore, while ensuring the survival rate of experimental models, the 75% SBR intestinal adaptation changes and microbial community alterations are more likely to simulate human short bowel syndrome and are more suitable for related research.

[0114] In summary, establishing a SBS model using mice is an ideal experimental model for studying the intestinal adaptation process in SBS due to its low cost and closer genetic homology to humans. By performing a 75% intestinal resection from 2 cm to 5-6 cm from the Treitz ligament to the ileocecal junction, and optimizing perioperative management, the survival rate of SBS mice was improved, successfully establishing an SBS mouse model. This addresses concerns about the reproducibility of the mouse intestinal resection model and demonstrates that the model's intestinal morphological adaptations and gut microbiota structure are more similar to human SBS disease, providing a reliable mouse model for intestinal adaptation and microbiome-related research, minimizing experimental variability.

[0115] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A perioperative management system for a mouse short bowel syndrome model, comprising a computer module, characterized in that: The computer module is electrically connected to a processing module, the processing module is electrically connected to a data input module and a medical monitoring module, and the processing module is electrically connected to a prediction model module. The data entry module is used to input various data information of the experimental mice, which facilitates the prediction of the mice's condition and subsequent lifespan, thereby improving the prediction accuracy of the prediction model module. The medical monitoring module is used to monitor the experimental mice in real time after surgery, detecting various vital signs of the mice, which allows the prediction model module to obtain the mice's vital signs in real time. The prediction model module is used to calculate the vital signs of the experimental mice and predict their lifespan by using the input and monitored data. The monitoring indicators of the data entry module and the medical monitoring module include body weight, food intake, ambient temperature, remaining jejunum, ileum length, and fecal 16S rDNA sequencing. Fecal 16S rDNA sequencing is used to determine the intestinal flora. The prediction model module uses Kaplan-Meier survival probability estimation, as shown in the following formula: The survival rate formula for the Kaplan-Meier survival curve is as follows: survival probability S(t) i The probability of survival at the previous time point i-1 is equal to the probability of survival multiplied by 1 and d. i / n i The product of the differences, n i It is t i Total number of survivors before point d i The event is in t i Number of occurrences, t i Let S(t) represent the i-th time point. i -1) represents the survival probability at the previous time point i-1; The prediction model module may employ the Cox proportional hazards regression model. The Cox model is a semi-parametric model because its formula includes both parametric and non-parametric components. The parameters of a parametric model are finite-dimensional, meaning a finite number of parameters represents the model distribution. In contrast, the parameters of a non-parametric model belong to an infinite-dimensional space and cannot be represented by a finite number of parameters. The Cox model formula is as follows: h(t)=h0(t)×exp(b1x1+b2x2+…+b p x p ), Where t is the survival time, from x1, x2 to x... p This refers to multiple variables with predictive effects, b1, b2 to b p This refers to the effect size, or effect size, for each variable, which can be understood as the degree of influence of the outcome. h(t) represents the hazard at different times t, i.e., the risk value, while h0(t) is the baseline hazard function, meaning that the hazard is determined by the other covariates x1, x2, ..., x... p When all values ​​are 0, i.e. when it has no effect, it is a function that measures risk.

2. The perioperative management system for the mouse short bowel syndrome model according to claim 1, characterized in that: The computer module is electrically connected to an adapter module, which includes a step-down circuit, a voltage regulator circuit, a filter circuit, a rectifier circuit, and a surge protection circuit. The step-down circuit reduces the voltage, the rectifier circuit converts AC voltage to DC voltage, the filter circuit filters out AC voltage from the DC voltage, the voltage regulator circuit stabilizes the supply voltage, and the surge protection circuit prevents voltage surges from damaging subsequent electronic equipment.

3. The perioperative management system for the mouse short bowel syndrome model according to claim 1, characterized in that: The computer module is electrically connected to a display module and a keyboard and mouse module. The display module is used to display the system's data information and predicted images, and the keyboard and mouse module is used to effectively control and adjust the system, and to facilitate the input of various parameter information of the experimental mice.

4. The perioperative management system for the mouse short bowel syndrome model according to claim 1, characterized in that: The processing module is electrically connected to a communication module, which is used to transmit the calculation data information of the prediction model module and the monitoring data information of the medical monitoring module, so that doctors can obtain them in a timely manner. The communication module is connected to a mobile device.

5. The perioperative management system for the mouse short bowel syndrome model according to claim 1, characterized in that: The computer module is electrically connected to an auxiliary module, which includes a status indicator light, an alarm, and a memory. The status indicator light is used to display the operating status of the system, the alarm is used to warn of system abnormalities, and the memory is used to store data information.

6. The perioperative management system for the mouse short bowel syndrome model according to claim 5, characterized in that: The status indicator lights include a power supply indicator light, a fault indicator light, a communication indicator light, and a running indicator light. The alarm device is an audible and visual alarm. The memory includes a ROM memory, a RAM memory, and a cache memory. The ROM memory is used to store the system's running program and algorithms, and the RAM memory is used to store data information and running logs.

7. The perioperative management system for the mouse short bowel syndrome model according to claim 1, characterized in that: The processing module includes an acquisition unit for receiving data information, a filtering unit for filtering out noise from the data information, a conversion unit for performing analog-to-digital conversion on the data information, and a gain unit for amplifying the data information.

8. The perioperative management system for the mouse short bowel syndrome model according to claim 7, characterized in that: The filtering unit uses a low-pass filter, which is a first-order filter, also called a first-order inertial filter or a first-order low-pass filter. The algorithm formula for the first-order low-pass filter is as follows: Y(n) = αX(n+(1-α)Y(n-1), In the formula: α = filter coefficient; X(n) = current sample value; Y(n-1) = previous filter output value; Y(n) = current filter output value. The first-order low-pass filtering method uses the current sample value and the previous filter output value to weight the effective filter value, so that the output has a feedback effect on the input.

9. The perioperative management system for the mouse short bowel syndrome model according to claim 1, characterized in that: The data entry module needs to enter data including preoperative body weight, intraoperative surgical procedures, postoperative dietary strategies and environmental temperature settings. The intraoperative surgical procedures include bowel resection length, anastomosis location and removal of bowel contents. The medical monitoring module includes vital sign monitoring, drug monitoring, drug abnormality monitoring, and drug use time monitoring. The vital sign monitoring includes blood pressure detection, heart rate monitoring, and respiration monitoring.

10. A method for perioperative management of a mouse short bowel syndrome model, characterized in that, It includes the following steps: S1. C57BL / 6J mice were selected. Perioperative management was optimized by controlling preoperative body weight, intraoperative surgical procedures, postoperative dietary strategies, and environmental temperature settings. Approximately 75% of the small intestine was removed, starting from 2 cm from the Treitz ligament and ending at 5-6 cm from the ileocecal junction. The contents of the small intestine were flushed before intestinal anastomosis. The mice were divided into 20-25g and 25-30g groups according to their preoperative weight. Postoperatively, the mice were divided into six groups according to their feeding restrictions (gradually increasing food intake) and non-restricted feeding, and environmental temperatures of 25°C and 30°C. The mice were followed up for 14 days postoperatively. The survival rates of SBS mice with body weights of 20-25g and 25-30g, feeding restrictions and non-restricted feeding, and environmental temperatures of 25°C and 30°C were compared. The length of the residual small intestine was measured. Hematoxylin-eosin staining and immunofluorescence were used to detect pathological changes in the residual intestine. Western blot was used to detect the expression of intestinal barrier-related proteins. 16S rDNA sequencing was used to study the changes in the intestinal microbiota of SBS mice. S2. Results: With postoperative day 14 as the observation endpoint, the survival rate of SBS mice in the 25-30g group was significantly higher than that in the 20-25g group (81.3% vs. 43.5%, p = 0.017). Postoperative food restriction significantly improved the survival rate (20.0% in the non-restricted food group and 81.3% in the restricted food group, p = 0.004). The mortality rate of mice reached 75% two days after surgery at 25℃, while all mice in the 30℃ group survived. S3. By 14 days post-surgery, the remaining jejunum and ileum lengths of SBS mice increased by 1.7-fold and 1.4-fold, respectively; villus heights of the jejunum and ileum increased by 1.5-fold and 1.4-fold, respectively; and crypt depths increased by 1.3-fold and 2.0-fold, respectively. Compared with the sham-operated group, the SBS group showed increased expression of Villin and Occludin. PCNA expression decreased significantly one week post-surgery, but increased over time. 16S rDNA sequencing analysis of feces from the ileocecal junction showed that 75% of SBR mice had dysbiosis, with low species diversity and richness. The relative abundance of Proteobacteria was increased, while the relative abundance of Bacteroidetes, Actinobacteria, and Cyanobacteria was decreased.

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