BACKGROUND:It has been proved clinically that adhesion of fibrous scar with the dura mater or nerve root after lumbar operation is an important factor for postoperative symptoms,such as postoperative pain and numbness. OBJECTIVE:To verify the inhibitory effect of autologous ligamentum flavum on the formation of epidural fibrous scar after lumbar surgery and explore the possible molecular biological mechanism. METHODS:Forty-eight Japanese white rabbits(6-8 months old)were randomly divided into three groups:a ligamentum flavum preservation group,a ligamentum flavum non-preservation group,and an autologous fat reposition group.A lumbar laminectomy model was established in all the three groups of rabbits,and rabbit epidural tissues were collected at 3 and 6 weeks after modeling.Hematoxylin-eosin staining was used to observe histological changes and the number and density of fibroblasts,VG staining was used to observe the percentage of collagen fiber area,and immunohistochemistry was used to observe the expression of transforming growth factor β1 and Smad3 proteins. RESULTS AND CONCLUSION:Hematoxylin-eosin staining results revealed that fibroblasts in the ligamentum flavum preservation group were few and loosely arranged,while the cells in the ligamentum flavum non-preservation and autologous fat reposition groups were more numerous and closely arranged.The number density of fibroblasts in the ligamentum flavum preservation group was lower than that in the ligamentum flavum non-preservation and autologous fat reposition groups at 3 and 6 weeks after surgery(P＜0.05);however,there was no significant difference between the latter two groups.VG staining results showed that the collagen fibers in the ligamentum flavum preservation group were sparse and distributed unevenly,while a lot of red collagen fibers were gathered in the ligamentum flavum non-preservation and autologous fat reposition groups.The area percentage of collagen fibers in the ligamentum flavum preservation group was lower than that in the ligamentum flavum non-preservation and autologous fat reposition groups at 3 and 6 weeks after surgery(P＜0.05),but there was no significant difference between the latter two groups.The results of immunohistochemistry showed that the degree of positive staining of retained histone the ligamentum flavum preservation group was significantly lower than that of the other two groups.The absorbance value of transforming growth factor β1 and Smad3 in the ligamentum flavum preservation group was significantly lower than that in the other two groups at 3 and 6 weeks after surgery(P＜0.05),but there was no significant difference between the latter two groups.To conclude,there are different degrees of epidural fibrous scar formation after lumbar surgery.If the ligamentum flavum is preserved,it can help to reduce the number of epidural fibroblasts as well as the formation of collagen fibers,thus reducing the adhesion of the fibrous scar tissue to the dural sac and nerve root.The mechanism is not only a purely mechanical blockade,but also to reduce the formation of epidural fibrous scar by interfering with the transforming growth factor β1/Smad3 signaling pathway.

BACKGROUND:Currently,there have been studies on three-dimensional digitalization and visualization systems for adult acupoints,but there are not many reports on the visualization of pediatric acupoints based on real pediatric digital sectional anatomical datasets. OBJECTIVE:To design and develop a digital three-dimensional visualization system for children's neck acupoints,to provide a basis for acupuncture and moxibustion,meridian and acupoint science teaching,clinical practice,acupuncture manipulation practice,and acupuncture safety research,and to provide a basis for the development of children's acupoint simulation system. METHODS:Based on a real cross-sectional anatomical dataset of pre-school boys,a three-dimensional digital virtual anatomical model of the neck region of children and internal multi-organ three-dimensional reconstruction were completed using PhotoShop 2021 and Digihuman Reconstruction System software.A database of 11 acupoints was compiled,including Fengfu and Fengchi,using the Unity database language.A three-dimensional model of children's neck anatomy,acupoint database,and writing acupuncture operation codes were integrated in Unity3D software.A three-dimensional digital visualization system for children's neck acupoints was successfully created,which integrated simulation acupoint positioning,three-dimensional acupoint anatomy,acupuncture training,clinical teaching,and acupuncture safety research. RESULTS AND CONCLUSION:(1)This study was based on real child specimens.Manual layer by layer segmentation of cross-sectional images was used to ensure the accuracy of the three-dimensional model to the greatest extent possible.The 3D software Digihuman Reconstruction System was utilized to extract and save independent segmentation data.PhotoShop 2021 software was collaborated with to complete dozens of three-dimensional reconstruction anatomical models of the outer skin of the neck and its internal bone structure,cervical spinal cord,blood vessels and nerves,muscles,and ligaments in children.The basic morphology and overall contour integrity verification of each independent structure were completed in MeshLab software.The 3-material research 13.0 software was applied for final fine tuning and anatomical position confirmation,successfully simulating and restoring the true anatomical morphology of the neck of preschool children.(2)Based on and referring to the national standards of the People's Republic of China,a database of commonly used acupoints in children's neck region was collected and organized,including their names,meridians,positioning,local anatomy,needle insertion levels,acupuncture methods,acupuncture accidents and prevention,acupoint indications,and two-dimensional anatomical sectional images.(3)Unity3D software was employed to integrate the three-dimensional model of children's neck,acupuncture simulation operation,and acupoint database,and a three-dimensional digital children's neck acupoint acupuncture visualization system was successfully constructed.The system displayed information on children's neck acupoints,two-dimensional and three-dimensional anatomical structures,and achieved two-dimensional and three-dimensional acupuncture simulation functions and acupuncture safety research functions for children's neck acupoints.Based on the ultra-thin sectional anatomical dataset of real child specimens,the first three-dimensional digital and visualization system for acupoints in the neck region of children had been constructed.Compared with previous acupoint acupuncture systems,it is more in line with the anatomical and morphological development characteristics of Asian children and has high application value in the fields of acupuncture safety research,clinical teaching,and acupuncture simulation training.

Food safety risk early warning is a crucial technical approach to ensure that regulation stays ahead of potential risks. In recent years, machine learning, as an emerging technology, has demonstrated its immense potential in food safety risk early warning due to its powerful data processing and analysis capabilities. This paper introduced the concept of food safety risk early warning and the current food safety risk early warning systems both domestically and internationally. It reviewed the main principles, basic characteristics, and application progress of various machine learning methods, including logistic regression, least absolute shrinkage and selection operator, support vector machine, random forest, Bayesian network, extreme gradient boosting, light gradient boosting machine, and artificial neural networks. The paper also presented the advantages and disadvantages of machine learning in current food safety risk early warning application scenarios, as well as future development directions. In particular, advanced technologies such as multimodal data fusion and deep learning are expected to play an increasingly important role in future food safety risk early warning.

Objective To study the inner ear appearance on three-dimensional real inversion recovery(3D re-al IR)imaging in patients with sudden sensorineural hearing loss,and to investigate the relationship between blood-labyrinth barrier permeability and pathogenesis and prognosis of sudden hearing loss.Methods A total of 41 pa-tients with sudden sensorineural hearing loss received 3D real IR at 3.0 T MRI,and the signal intensity of inner ear were recorded.We respectively measured cochlear signal intensity in affected and healthy ears,and medullary signal intensity,and calculated the cochlear/medulla ratio(CM ratio)separately.On the basis of CM ratio,we evaluated hearing levels at initial and after treatment,and the relationship between CM ratio and hearing prognosis.Results Among the 41 patients,33 cases(occupying 80.48％)individually had a higher CM ratio in the affected ear than in the healthy one.The CM ratio of the affected side was not higher than that of the healthy side in 8 cases,and the ef-fective rate was 100％,eighteen cases had below 1.5 times the CM ratio in affected ears as in healthy ears,with 77.78％effective rate of treatment;seven cases had 1.5 to 1.75 times,with 100％effective rate;two cases had 1.75 to 2 times,with 50％effective rate;and the rest 14 cases had over 2 times,with 14.28％effective rate(P＜0.05).Conclusion The variation of blood-labyrinth barrier permeability in patients with sudden hearing loss can be read on the 3D Real IR,and it indicates that 80.48％patients have higher-intensity signals in lateral cochlea.The CM ratio can be adopted to evaluate the extent of inner ear damage of patients more accurately.As the CM ratio ri-ses,patients'prognosis become worse,and patients with over 1.75 times the CM ratio in the affected ear as in the healthy one,mostly suffer poor prognosis.

Objective     To investigate the effects of different types of tricuspid regurgitation, implantation positions, and device models on the treatment outcomes of K-Clip for tricuspid regurgitation using numerical simulations. Methods     Three-dimensional reconstruction of the heart model was performed based on CT images. Two different regurgitation orifices were obtained by modifying the standard parameterized tricuspid valve leaflets and chordae tendineae. The effects of different K-Clip models at different implantation positions (posterior leaflet midpoint, anterior-posterior commissure, anterior leaflet midpoint, posterior septal commissure) were simulated using commercial explicit dynamics software Ls-Dyna. Conclusion     For the two types of regurgitation in this study, clipping at the posterior leaflet midpoint resulted in a better reduction of the regurgitation orifice (up to 75% reduction in area). Higher clamping forces were required for implantation at the anterior leaflet midpoint and posterior septal commissure, which was unfavorable for the smooth closure of the clipping components. There was no statistical difference in the treatment outcomes between the 18T and 16T K-Clip components, and the 16T component required less clamping force. Therefore, the use of the 16T K-Clip component is recommended.

Noise is a common occupational hazard in workplaces. Long-term exposure to high-intensity noise mainly causes occupational noise-induced hearing loss (ONIHL). The development of ONIHL is irreversible, and there is currently no cure. At present, risk assessment methods based on noise exposure intensities mainly include risk index assessment method, Engineering Professional Council assessment method in United Kingdom (EDC assessment method in UK), National Institute of Occupational Safety and Health assessment method in United State (NIOSH assessment method in US), and International Standardization Organization assessment method (ISO assessment method). However, the risk index assessment method is subjective and does not consider the effectiveness of workers wearing protective equipment. The EDC assessment method in UK defines ONIHL differently from China. The NIOSH assessment method in US and ISO assessment methods have population data sources that deviate from China, which can lead to bias in risk assessment. In the future, it is necessary to further carry out application research on the risk assessment of ONIHL in Chinese noise-exposed workers, compare the applicabilities of various assessment methods, conduct large-sample population epidemiological studies for verification, and fully utilize the risk-prediction function to prevent and control ONIHL.

ObjectiveTo analyze the results of fit testing and its influencing factors on half-mask respirator among workers exposed to organic solvents. Methods A total of 84 workers exposed to organic solvents were selected as the research subjects using a convenience sampling method. The qualitative fit test apparatus of respiratory protection was tested after the workers had put on the half-mask respirats, and 11 facial indicators of the subjects were measured. Results The overall pass rate of the respirator fit testing was 71.4% (60/84). The lowest pass rate was 63.1% (53/84), which occurred during bending movements of workers. The head width, minimum forehead width, face length, nose length, nose depth, head circumference and head length were higher in workers who passed respirator fit testing, compared with those in the failing group (all P<0.05). The result of binary logistic regression analysis showed that gender and face width were influencing factors of the respirator fit testing (both P<0.05). Female workers had a lower pass rate of the fit testing than male workers, and workers with larger face width had a lower pass rate in the fit testing. Conclusion Drastic movement may lead to a decrease in the seal of half-mask respirator of workers exposed to organic solvents. When providing half-mask respirator to workers exposed to organic solvents, employers need to pay attention to the fit of respirators of female works and those with larger face width to ensure the effectiveness of respiratory protection for workers.

BACKGROUND:Previous brain studies have mostly focused on adults and fetuses,and the developmental characteristics of young children's brainstems have rarely been studied. OBJECTIVE:To observe the brainstem development characteristics of healthy young children and to explore the age-related differences and their correlation with sex. METHODS:From January 2019 to April 2022,a retrospective study of 3.0T MRI images of 174 children aged 2 to 6 years in the Affiliated Hospital of Inner Mongolia Medical University was conducted,and the median sagittal diameter,area and angle of the brainstem(including midbrain,pons and medulla oblongata)were measured. RESULTS AND CONCLUSION:There is an age-related increase in the anterior and posterior diameters of the midbrain,pons and medulla oblongata in the 2-5 years old group as well as in the longitudinal diameter and area of the midbrain,pons and medulla oblongata in the 2-6 years old group.Except for the longitudinal diameter of the medulla oblongata,all others show a positive correlation with age(r>0,P<0.05).In the 2-3 years old group and 4-5 years old group,the children are in the rapid growth and development stage,and these two age groups can be used as the key observation indicators for the development of young children.The anterior-posterior diameter,longitudinal diameter,area of the pons and total brainstem area are strongly correlated with age,which can be used as the key observation indicators for the brainstem development in young children.

BACKGROUND:The lower cervical vertebral pedicle is the main stress site of the posterior column of the spine,which is of great significance for the maintenance of the stability of the human center of gravity and the reduction of shock.At present,there are few reports on the characteristics of the internal bone trabeculae,and the characteristics of the joint site of the vertebral pedicle with the articular process and the vertebral body.It is urgent to understand the fine anatomical structure of the vertebral pedicle and the relationship and function of each part. OBJECTIVE:To observe the microanatomical morphology of the vertebral pedicle by Micro-CT scanning of cervical vertebra specimens,and to measure and analyze the microstructure and morphometric parameters of the bone trabecula in the cervical pedicle under normal conditions to evaluate the safety performance of the cervical spine. METHODS:Micro-CT scanning was performed on 31 sets of cervical vertebrae C3-C7.By checking and reconstructing the areas of interest in the bone trabecular within the vertebral pedicle,the morphological characteristics and distribution direction of the bone trabecular within the cervical pedicle were observed,and the bone microstructure parameters were detected,and the differences in the bone microstructure of the C3-C7 vertebral pedicle were analyzed and compared. RESULTS AND CONCLUSION:(1)The Micro-CT images showed that the honeycomb bone trabeculae of the pedicle of the lower cervical spine presented a complex network of microstructures.The trabeculae near the cortical bone were lamellar and relatively compact,extending forward toward the vertebral body and backward toward the articular process lamina.Abatoid bone trabeculae extended into the medullary cavity and transformed into a network structure,and then into rod-shaped bone trabeculae.The rod-shaped bone trabeculae were sparsely distributed in the medullary cavity.(2)Statistical results of morphological parameters of bone trabeculae showed that bone volume fraction values in C4 and C5 were higher than that in C7(P＜0.05).The bone surface/bone volume value in C7 was higher than that in C3,C4 and C6(P＜0.05).The bone surface density of bone trabeculae in C7 was higher than that in C3,C4,C5 and C6(P＜0.05).Trabecular thickness in C7 was higher than that in C3,C4 and C5(P＜0.05).Bone surface/bone volume and bone surface density of the left pedicle bone trabecular were greater than those on the right side(P＜0.05).(3)The microstructural changes of C3-C7 were summarized,in which the load capacity and stress of the C7 pedicle were poor,and the risk of injury was high in this area.

BACKGROUND:Due to the young age of children,the occipital condyle and foramen magnum are not fully developed,and they are prone to various diseases and injuries in the occipitocervical junction,which requires surgical treatment in severe cases.However,anatomical parameters for the development of the occipital condyle and foramen magnum in children are lacking. OBJECTIVE:To measure the morphological structure of the occipital condyle and foramen magnum by three-dimensional reconstruction technique,and to provide important anatomical parameters for occipitocervical junction lesions,related surgical procedures and forensic identification. METHODS:Imaging data of 389 cases of primitive children and adolescents involved in skull base undergoing spiral CT scanning(247 males and 142 females)aged 1-18 years were collected and divided into 1-3-year-old group,4-6-year-old group,7-9-year-old group,10-12-year-old group,13-15-year-old group,and 16-18-year-old group according to their age.Mimics 16.0 software was used to reconstruct the skull base and measure the length and width of the foramen magnum.A formula was used to calculate the area and index of the foramen magnum.We measured the length,width and height of the occipital condyle,the angle between the long axis and the sagittal axis of the occipital condyle(O-S angle),the included angle between the midpoint of the front and back edges of the foramen magnum and the connection between the back edge of occipital condyle and the intersection point of the foramen magnum(F-O angle),and the included angle between the midpoint of the front and back edges of the foramen magnum and the midpoint of the back wall of the sublingual neural tube(F-H angle).Gender,side and age differences were analyzed among the indicators. RESULTS AND CONCLUSION:(1)In foramen magnum measurement,there was no significant difference between sexes in the index of the foramen magnum(P>0.05),but there were significant differences in length,width and area of the foramen magnum(P<0.05).(2)The O-S angle,F-O angle and F-H angle of the occipitral condyle were not significantly different between genders(P>0.05),but length,width and height of the occipital condyle were significantly different between genders(P<0.05).(3)There were no significant differences in the length of the occipital condyle among different groups(P>0.05),but there were significant differences in the width and height of the occipital condyle,O-S angle,F-O angle and F-H angle among different groups(P<0.05).(4)Length,width and area of the foramen magnum,length,width and height of the occipital condyle showed a wavy increasing trend with the increase of age,while O-S,F-O and F-H angles showed a wavy decreasing trend with the increase of age,while the index of the foramen magnum showed no significant change.(5)In conclusion,there are gender and lateral differences in the morphological indexes of the foramen magnum and the occipital condyle in children.These differences can provide an important reference for clinical surgical approach selection and forensic examination.