1.Identification and Biological Characterization of Pathogen and Screening of Effective Fungicides for Wilt of Tetradium ruticarpum
Yuxin LIU ; Qin XU ; Yue YUAN ; Tiantian GUO ; Zheng'en XIAO ; Shaotian ZHANG ; Ming LIU ; Fuqiang YIN
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(2):198-206
ObjectiveTo identify the pathogen species responsible for the wilt disease of Tetradium ruticarpum in Chongqing, investigate there biological characteristics, and screen effective fungicides, so as to provide a theoretical basis for disease control in production. MethodsThe pathogen was isolated via the tissue culture method. Pathogenicity was verified according to Koch's postulates. The pathogen was identified based on morphological characteristics and multi-gene phylogenetic analysis. The mycelial growth rate method was used for biological characterization of the pathogen and fungicide screening. ResultsThe pathogen colonies were nearly circular with irregular edges, white, short, velvety aerial hyphae, and pale purple undersides. Macroconidia were colorless, sickle-shaped, with 3-5 septa, while microconidia were transparent, elliptical, aseptate or with 1-2 septa. Multi-gene phylogenetic analysis showed that the pathogen clustered in the same clade as Fusarium fujikuroi with 100% support, which, combined with morphological characteristics, identified the pathogen causing wilt of T. ruticarpum in Chongqing as F. fujikuroi. The optimal conditions for the mycelial growth of F. fujikuroi were mung bean agar (MBA) with glucose as the carbon source, beef extract and yeast powder as nitrogen sources, 28 ℃, pH 7.0, and alternating light/dark conditions. The optimal conditions for sporulation were potato dextrose agar (PDA) with glucose as the carbon source, beef extract as the nitrogen source, 28 ℃, pH 7.0, and complete darkness. Among chemical fungicides, phenazine-1-carboxylic acid exhibited the strongest inhibitory effect on F. fujikuroi. Shenqinmycin and tetramycin were the most effective bio-fungicides. ConclusionThis study is the first to report F. fujikuroi as the causal agent of wilt disease in T. rutaecarpa. The chemical fungicide phenazine-1-carboxylic acid and the bio-fungicides shenqinmycin and tetramycin showed strong inhibitory effects against F. fujikuroi.
2.Constructing a model of degenerative scoliosis using finite element method:biomechanical analysis in etiology and treatment
Kai HE ; Wenhua XING ; Shengxiang LIU ; Xianming BAI ; Chen ZHOU ; Xu GAO ; Yu QIAO ; Qiang HE ; Zhiyu GAO ; Zhen GUO ; Aruhan BAO ; Chade LI
Chinese Journal of Tissue Engineering Research 2025;29(3):572-578
BACKGROUND:Degenerative scoliosis is defined as a condition that occurs in adulthood with a coronal cobb angle of the spine>10° accompanied by sagittal deformity and rotational subluxation,which often produces symptoms of spinal cord and nerve compression,such as lumbar pain,lower limb pain,numbness,weakness,and neurogenic claudication.The finite element method is a mechanical analysis technique for computer modelling,which can be used for spinal mechanics research by building digital models that can realistically restore the human spine model and design modifications. OBJECTIVE:To review the application of finite element method in the etiology and treatment of degenerative scoliosis. METHODS:The literature databases CNKI,PubMed,and Web of Science were searched for articles on the application of finite element method in degenerative scoliosis published before October 2023.Search terms were"finite element analysis,biomechanics,stress analysis,degenerative scoliosis,adult spinal deformity"in Chinese and English.Fifty-four papers were finally included. RESULTS AND CONCLUSION:(1)The biomechanical findings from the degenerative scoliosis model constructed using the finite element method were identical to those from the in vivo experimental studies,which proves that the finite element method has a high practical value in degenerative scoliosis.(2)The study of the etiology and treatment of degenerative scoliosis by the finite element method is conducive to the prevention of the occurrence of the scoliosis,slowing down the progress of the scoliosis,the development of a more appropriate treatment plan,the reduction of complications,and the promotion of the patients'surgical operation.(3)The finite element method has gradually evolved from a single bony structure to the inclusion of soft tissues such as muscle ligaments,and the small sample content is increasingly unable to meet the research needs.(4)The finite element method has much room for exploration in degenerative scoliosis.
3.Gradient artificial bone repair scaffold regulates skeletal system tissue repair and regeneration
Yu ZHANG ; Ruian XU ; Lei FANG ; Longfei LI ; Shuyan LIU ; Lingxue DING ; Yuexi WANG ; Ziyan GUO ; Feng TIAN ; Jiajia XUE
Chinese Journal of Tissue Engineering Research 2025;29(4):846-855
BACKGROUND:Gradient artificial bone repair scaffolds can mimic unique anatomical features in musculoskeletal tissues,showing great potential for repairing injured musculoskeletal tissues. OBJECTIVE:To review the latest research advances in gradient artificial bone repair scaffolds for tissue engineering in the musculoskeletal system and describe their advantages and fabrication strategies. METHODS:The first author of the article searched the Web of Science and PubMed databases for articles published from 2000 to 2023 with search terms"gradient,bone regeneration,scaffold".Finally,76 papers were analyzed and summarized after the screening. RESULTS AND CONCLUSION:(1)As an important means of efficient and high-quality repair of skeletal system tissues,gradient artificial bone repair scaffolds are currently designed bionically for the natural gradient characteristics of bone tissue,bone-cartilage,and tendon-bone tissue.These scaffolds can mimic the extracellular matrix of native tissues to a certain extent in terms of structure and composition,thus promoting cell adhesion,migration,proliferation,differentiation,and regenerative recovery of damaged tissues to their native state.(2)Advanced manufacturing technology provides more possibilities for gradient artificial bone repair scaffold preparation:Gradient electrospun fiber scaffolds constructed by spatially differentiated fiber arrangement and loading of biologically active substances have been developed;gradient 3D printed scaffolds fabricated by layered stacking,graded porosity,and bio-3D printing technology;gradient hydrogel scaffolds fabricated by in-situ layered injections,simple layer-by-layer stacking,and freeze-drying method;and in addition,there are also scaffolds made by other modalities or multi-method coupling.These scaffolds have demonstrated good biocompatibility in vitro experiments,were able to accelerate tissue regeneration in small animal tests,and were observed to have significantly improved histological structure.(3)The currently developed gradient artificial bone repair scaffolds have problems such as mismatch of gradient scales,unclear material-tissue interactions,and side effects caused by degradation products,which need to be further optimized by combining the strengths of related disciplines and clinical needs in the future.
4.Therapeutic effect and mechanism by which Trichosanthis Fructus-Allii Macrostemonis Bulbus regulates gut microbiota in a rat model of coronary heart disease
Guanghan SUN ; Zhencong XIE ; Mi SUN ; Yang XU ; Dong GUO
Chinese Journal of Tissue Engineering Research 2025;29(5):917-927
BACKGROUND:A network-based pharmacological approach has identified multifunctional effects of the main bioactive compounds in the Trichosanthis Fructus-Allii Macrostemonis Bulbus on coronary heart disease;however,the mechanism of its therapeutic effect on coronary heart disease has not been fully elucidated. OBJECTIVE:To investigate the role and mechanism of Trichosanthis Fructus-Allii Macrostemonis Bulbus in improving coronary heart disease by regulating the composition of gut microbiota. METHODS:Forty Sprague-Dawley rats were randomly divided into four groups:blank control group(n=10),model group(n=10),positive drug group(n=10),and medicine pair group(n=10).A rat model of coronary heart disease was established by continuous gastric perfusion of fat emulsion and injection of pituitrin.After modeling,rats in the model group were gavaged with distilled water(10 mL/kg)for control,rats in the positive drug group were gavaged with simvastatin 4 mg/kg per day,and rats in the medicine pair group were gavaged with Trichosanthis Fructus-Allii Macrostemonis Bulbus pairs 7.56 g/kg per day.All interventions lasted for 14 days.Electrocardiograms and myocardial pathology were observed,and blood lipid levels were measured.The structure of gut microbiota was analyzed using 16S rDNA sequencing technology. RESULTS AND CONCLUSION:Electrocardiogram results showed ST segment elevation in the model group.There were no significant abnormalities in the electrocardiograms of the positive drug group and medicine pair group.Compared with the blank control group,the levels of total cholesterol,triacylglycerol,and low-density lipoprotein cholesterol were significantly higher in the model group(P<0.05).Compared with the model group,the levels of total cholesterol,triacylglycerol,and low-density lipoprotein cholesterol were significantly lower in the positive drug group and medicine pair group(P<0.05).Compared with the blank control group,focal myocardial cell necrosis was observed in the model group,while partial myocardial cell disarray was observed in the positive drug group and medicine pair group.Compared with the blank control group,the Ace,Shannon,and Chao indices were increased(P<0.05)and the Simpson index was decreased(P<0.05)in the model group,positive drug group and medicine pair group.Compared with the model group,the Ace and Chao indices were decreased(P<0.05),while the Shannon index showed no significant difference(P>0.05)and the Simpson index was also decreased(P<0.05)in the positive drug group and medicine pair group.Compared with the blank control group,the relative abundances of Desulfovibrionia,Muribaculaceae_norank,etc.were increased in the model group,while those of Clostridia,[Eubacterium]_coprostanoligenes_group_norank,etc.were decreased.Compared with the model group,the relative abundances of WPS-2_norank,Muribaculaceae_norank,etc.were increased in the medicine pair group,while those of Clostridia,[Eubacterium]_coprostanoligenes_group_norank,etc.were decreased;the relative abundances of Desulfobacterota,[Eubacterium]_coprostanoligenes_group_norank,etc.were increased in the positive drug group,while those of Firmicutes,Muribaculaceae_norank,etc.were decreased.Compared with the positive drug group,the relative abundances of Desulfobacterota,Bacteroides,etc.were increased in the medicine pair group,while those of Firmicutes,[Eubacterium]_coprostanoligenes_group_norank,etc.were decreased.The LEfSe results showed that the medicine pair group had the highest microbial enrichment,followed by the blank control group and positive drug group,with the model group having the lowest microbial enrichment.To conclude,Trichosanthis Fructus-Allii Macrostemonis Bulbus pairs can improve the development of coronary heart disease by regulating gut microbiota composition,providing new insights for further research and development of Trichosanthis Fructus-Allii Macrostemonis Bulbus pairs.
5.Metformin exerts a protective effect on articular cartilage in osteoarthritis rats by inhibiting the PI3K/AKT/mTOR pathway
Tianjie XU ; Jiaxin FAN ; Xiaoling GUO ; Xiang JIA ; Xingwang ZHAO ; Kainan LIU ; Qian WANG
Chinese Journal of Tissue Engineering Research 2025;29(5):1003-1012
BACKGROUND:Studies have shown that metformin has anti-inflammatory,anti-tumor,anti-aging and vasoprotective effects,and can inhibit the progression of osteoarthritis,but its specific mechanism of action remains unclear. OBJECTIVE:To investigate the mechanism of metformin on cartilage protection in a rat model of osteoarthritis. METHODS:Forty male Sprague-Dawley rats were randomly divided into four groups(n=10 per group):blank,control,sham-operated,and metformin groups.The blank group did not undergo any surgery.In the sham-operated group,the joint cavity was exposed.In the model group and the metformin group,the modified Hulth method was used to establish the osteoarthritis model.At 1 day after modeling,the rats in the metformin group were given 200 mg/kg/d metformin by gavage,and the model,blank,and sham-operated groups were given normal saline by gavage.Administration in each group was given for 4 weeks consecutively.Hematoxylin-eosin staining,toluidine blue staining,and safranin O-fast green staining were used to observe the morphological structure of rat knee joints.Immunohistochemical staining and western blot were used to detect the protein expression of SOX9,type Ⅱ collagen,a disintegrin and metalloproteinase with thrombospondin motifs 5(ADAMTS5),Beclin1,P62,phosphatidylinositol 3-kinase(PI3K),p-PI3K,protein kinase B(AKT),p-AKT,mammalian target of rapamycin(Mtor),and p-Mtor in rat cartilage tissue. RESULTS AND CONCLUSION:The results of hematoxylin-eosin,toluidine blue and safranin O-fast green staining showed smooth cartilage surface of the knee joints and normal histomorphology in the blank group and the sham-operated group,while in the model group,there was irregular cartilage surface of the knee joint and cartilage damage,with a decrease in the number of chondrocytes and the content of proteoglycans in the cartilage matrix.In the metformin group,there was a significant improvement in the damage to the structure of the cartilage in the knee joints of the rats,and the cartilage surface tended to be smooth,with an increase in the number of chondrocytes and the content of proteoglycans in the cartilage matrix.Immunohistochemistry staining and western blot results showed that compared with the control and sham-operated groups,the expression of SOX9,type Ⅱ collagen,and Beclin1 proteins in the cartilage tissue of rats in the model group was significantly decreased(P<0.05).Conversely,the expression of ADAMTS5,P62,as well as p-PI3K,p-AKT,and p-Mtor proteins was significantly increased(P<0.05).Furthermore,compared with the model group,the expression of SOX9,type Ⅱ collagen,and Beclin1 proteins in the cartilage tissue of rats in the metformin group was significantly increased(P<0.05),while the expression of ADAMTS5,P62,as well as p-PI3K,p-AKT,and p-Mtor proteins was significantly decreased(P<0.05).To conclude,Metformin can improve the autophagy activity of chondrocytes and reduce the degradation of cartilage matrix in osteoarthritis rats by inhibiting the activation of PI3K/AKT/Mtor signaling pathway,thus exerting a protective effect on articular cartilage.
6.Effect of transcranial magneto-acousto-electrical stimulation on the plasticity of the prefrontal cortex network in mice
Shuai ZHANG ; Zichun LI ; Yihao XU ; Xiaofeng XIE ; Zhongsheng GUO ; Qingyang ZHAO
Chinese Journal of Tissue Engineering Research 2025;29(6):1108-1117
BACKGROUND:Transcranial magneto-acoustic-electrical stimulation is a novel non-invasive neural regulation technique that utilizes the induced electric field generated by the coupling effect of ultrasound and static magnetic field to regulate the discharge activity of the nervous system.However,the mechanism by which it affects synaptic plasticity in the brain is still not enough. OBJECTIVE:To explore the effect of transcranial magneto-acoustic-electrical stimulation intensity on synaptic plasticity of the prefrontal cortex neural network in mice. METHODS:(1)Animal experiment:Twenty-four C57 mice were equally and randomly divided into four groups:the control group receiving pseudo-stimulation,the 6.35 W/cm2 stimulation group receiving coupled stimulation of 0.3 T,6.35 W/cm2,the 17.36 W/cm2 stimulation group receiving coupled stimulation of 0.3 T,17.36 W/cm2,and the 56.25 W/cm2 stimulation group receiving coupled stimulation of 0.3 T,56.25 W/cm2.The local field potential signals and behavioral correctness were recorded during the execution of T-maze in mice.(2)Modeling and simulation experiments:A neural network model of the prefrontal cortex in mice stimulated by transcranial magneto-acoustic-electrical stimulation was constructed to compare the structural connectivity characteristics of the neural network under different stimulation intensities. RESULTS AND CONCLUSION:Transcranial magneto-acoustic-electrical stimulation could effectively shorten the behavior learning time,improve the working memory ability of mice(P<0.05),and continue to stimulate the frontal lobe of mice after learning behavior.There was no significant difference in the accuracy of the T-maze behavioral experiment among the experimental groups(P>0.1).Analysis of local field potential signals in the frontal lobe of mice revealed that transcranial magneto-acoustic-electrical stimulation promoted energy enhancement of β and γ rhythms.As the stimulation intensity increased,there was an asynchronous decrease in β and γ rhythms.Through β-γ phase amplitude coupling,it was found that stimuli could enhance the neural network's ability to adapt to new information and task requirements.Modeling and simulation experiments found that stimulation could enhance the discharge level of the neural network,increase the long-term synaptic weight level,and decrease the short-term synaptic weight level only when the stimulation intensity was high.To conclude,there is a complex nonlinear relationship between different stimulus intensities and the functional structure of neural networks.This neural regulation technique may provide new possibilities for the treatment of related neurological diseases such as synaptic dysfunction and neural network abnormalities.
7.Material basis and action mechanism of drug-containing serum of Modified Erxian Pill inhibiting macrophage pyroptosis
Siyuan LI ; Yuru WANG ; Ye XU ; Di GUO ; Nan NAN ; Yang LIU ; Jie ZHAO ; Huiqin HAO
Chinese Journal of Tissue Engineering Research 2025;29(19):4029-4037
BACKGROUND:Our previous study found that Modified Erxian Pill could alleviate inflammation in collagen-induced arthritis rats,but its mechanism needs to be further verified. OBJECTIVE:To analyze the components absorbed in the blood of Modified Erxian Pill,and observe the effect of the drug-containing serum of Modified Erxian Pill on pyroptosis of J774A.1 macrophages. METHODS:(1)Analysis of components absorbed in the blood of Modified Erxian Pill:Ultra-high performance liquid chromatography-high resolution mass spectrometry was used to detect and identify Modified Erxian Pill and its components absorbed in the blood.(2)Effect of the drug-containing serum of Modified Erxian Pill on pyroptosis of J774A.1 macrophages:Molecular docking technology was used to initially verify the sesquiterpenoids and NLRP3 in components absorbed in the blood of Modified Erxian Pill.J774A.1 macrophages were randomly divided into blank control group,lipopolysaccharide+adenosine triphosphate group,and lipopolysaccharide+adenosine triphosphate+Modified Erxian Pill with low(2.5%),medium(5%),and high(10%)dose groups.The release of lactate dehydrogenase in the cell supernatant of each group was detected according to the kit instructions.The levels of interleukin-1β and interleukin-18 in cell supernatant were detected in each group by ELISA.The cell membrane damage was detected by Hoechst/PI staining.The expression levels of NLRP3,Caspase-1,GSDMD,and GSDMD-N protein in the cells of each group were detected by western blot assay. RESULTS AND CONCLUSION:(1)A total of 32 active components of Modified Erxian Pill were identified,and 21 components entered the blood.The main components into blood included a variety of sesquiterpenoids.(2)Molecular docking results showed that 3-O-Acetyl-13-deoxyphomenone,Incensol oxide,Atractylenolide III,Rupestonic acid,and 3,7-Dihydroxy-9,11-eremophiladien-8-one had good binding activity with NLRP3.(3)Compared with the blank control group,lactate dehydrogenase activity and the expression levels of interleukin-1β and interleukin-18 were significantly increased in cell supernatant of lipopolysaccharide+adenosine triphosphate group(P<0.001).Hoechst/PI staining showed that the number of PI-positive cells was significantly increased.After the intervention of lipopolysaccharide+adenosine triphosphate+Modified Erxian Pill group,all of them showed different degrees of reduction.(4)Compared with the blank control group,NLRP3,Caspase-1,GSDMD,and GSDMD-N protein expression levels were significantly increased in the lipopolysaccharide+adenosine triphosphate group(P<0.05).Compared with lipopolysaccharide+adenosine triphosphate group,the protein expressions of NLRP3,Caspase-1,GSDMD,and GSDMD-N were significantly decreased in the lipopolysaccharide+adenosine triphosphate+Modified Erxian Pill group(P<0.05),and had a certain dose dependence.These findings verify that the drug-containing serum of Modified Erxian Pill may inhibit the pyroptosis of J774A.1 macrophages by regulating the NLRP3/Caspase-1/GSDMD pathway.
8.Isolation,culture and differentiation of human urine-derived stem cells into smooth muscle cells
Jiahui CHEN ; Xiaoqi DAI ; Yangang XU ; Yuanchao LI ; Mei HUANG ; Yifei ZHAN ; Yuxuan DU ; Liuqiang LI ; Yaochuan GUO ; Jun BIAN ; Dehui LAI
Chinese Journal of Tissue Engineering Research 2025;29(19):4076-4082
BACKGROUND:Traditional methods of urinary tract reconstruction are limited by donor scarcity,high complication rates,and suboptimal functional recovery.Tissue engineering strategies offer new directions in this field.Since the urinary tract is mainly composed of muscle tissue,the key is to find suitable seed cells and efficiently induce them to differentiate into smooth muscle cells.Comparative studies on the efficacy of different smooth muscle cell induction regimens are still lacking. OBJECTIVE:To isolate,culture,and identify human urine-derived stem cells,and to compare the effects of two different induction protocols. METHODS:Human urine-derived stem cells were isolated from urine samples of 11 healthy adult volunteers by multiple centrifugations.Surface markers were identified by flow cytometry.The multi-directional differentiation potential of human urine-derived stem cells was verified through osteogenic and adipogenic differentiation.Differentiation was induced by transforming growth factor-β1 or transforming growth factor-β1 combined with platelet derived growth factor for 14 days.Immunofluorescence staining and western blot assay were employed to compare the expression differences of smooth muscle-specific proteins(α-SMA and SM22). RESULTS AND CONCLUSION:(1)Urine-derived stem cells were successfully isolated from the eight urine samples of healthy people.These cells exhibit a"rice grain"-like morphology and possess a robust proliferative capacity.(2)Urine-derived stem cells exhibited high expression of mesenchymal stem cell surface markers(CD73,CD90,and CD44)and extremely low expression of hematopoietic stem cell surface markers(CD34 and CD45).These cells did not express CD19,CD105,and HLA-DR.(3)After osteogenic and adipogenic differentiation,the formation of calcium nodules and lipid droplets was observed,with positive staining results from Alizarin Red S and Oil Red O staining.(4)After 14 days of smooth muscle induction culture,immunofluorescence staining revealed that the smooth muscle differentiation rate of urine-derived stem cells treated with a combination of transforming growth factor-β1 and platelet derived growth factor was significantly higher compared to those treated with transforming growth factor-β1 alone(P<0.005).(5)After 14 days of smooth muscle induction culture,western blot assay further demonstrated that the expression levels of α-SMA and SM22 in the transforming growth factor-β1/platelet derived growth factor group were significantly elevated compared to those in the transforming growth factor-β1 only group(P<0.005).These findings confirm that urine-derived stem cells can be non-invasively isolated using multiple rounds of centrifugation.Compared with transforming growth factor-β1 alone,the combination of transforming growth factor-β1 and platelet derived growth factor can improve the efficiency of inducing urine-derived stem cells to differentiate into smooth muscle cells.
9.Disease burden of chronic kidney disease attributable to high BMI in China and trend prediction in 1992-2021
Hong LIU ; Guimao YANG ; Yan SUI ; Xia ZHANG ; Xuebing CHENG ; Yaxing WU ; Xu GUO ; Yanfeng REN
Journal of Public Health and Preventive Medicine 2025;36(1):27-31
Objective To analyze the disease burden of chronic kidney diseases (CKD) attributed to high body mass index (BMI) in China from 1992 to 2021 and predict the disease burden for the next decade, and to provide evidence for the prevention and treatment of CKD. Methods Using the Global Burden of Disease (GBD) database and the Joinpoint model, the average annual percentage rate change (AAPC) of the mortality rate and disability-adjusted life year (DALY) rate was calculated to describe and analyze the CKD disease burden attributed to high BMI in China from 1992 to 2021. The ARIMA model was employed to predict and analyze the change trend of the CKD disease burden. Results From 1992 to 2021, the mortality rate and DALY rate attributed to high BMI-induced chronic kidney disease showed an upward trend. Compared to 1992, the attributed number of deaths increased by 324.38%, and DALYs increased by 268.56%; the mortality rate increased by 64.00%, and the DALY rate grew by 51.62%. From 1992 to 2021, the mortality rate and DALY rate for males were lower than those for females, but the growth rate for males exceeded that of females. From 1992 to 2021, the mortality rate and DALY rate of chronic kidney disease attributed to high BMI in China increased with age. The average annual change rate of chronic kidney disease attributed to high BMI in China from 1992 to 2021 (mortality rate: 1.40 per 100,000 (95% CI: 1.04–1.76), DALY rate: 1.43 per 100 000 (95% CI: 1.17–1.70)) was higher than thHuaiyin Normal University, Huai'anher social demographic index (SDI) regions. The ARIMA model predicted that the age-standardized mortality rate increased from 2.91 per 100 000 in 2022 to 3.05 per 100 000 in 2026, and the age-standardized DALY rate increased from 69.65 per 100 000 in 2022 to 73.58 per 100 000 in 2026. Conclusion Chronic kidney disease attributed to high BMI in China is on the rise, and it will continue to grow in the future. The focus of CKD prevention and control should be on males and the elderly, while active measures should be taken to reduce the occurrence and progression of chronic kidney disease.
10.Research and Application of Scalp Surface Laplacian Technique
Rui-Xin LUO ; Si-Ying GUO ; Xin-Yi LI ; Yu-He ZHAO ; Chun-Hou ZHENG ; Min-Peng XU ; Dong MING
Progress in Biochemistry and Biophysics 2025;52(2):425-438
Electroencephalogram (EEG) is a non-invasive, high temporal-resolution technique for monitoring brain activity. However, affected by the volume conduction effect, EEG has a low spatial resolution and is difficult to locate brain neuronal activity precisely. The surface Laplacian (SL) technique obtains the Laplacian EEG (LEEG) by estimating the second-order spatial derivative of the scalp potential. LEEG can reflect the radial current activity under the scalp, with positive values indicating current flow from the brain to the scalp (“source”) and negative values indicating current flow from the scalp to the brain (“sink”). It attenuates signals from volume conduction, effectively improving the spatial resolution of EEG, and is expected to contribute to breakthroughs in neural engineering. This paper provides a systematic overview of the principles and development of SL technology. Currently, there are two implementation paths for SL technology: current source density algorithms (CSD) and concentric ring electrodes (CRE). CSD performs the Laplace transform of the EEG signals acquired by conventional disc electrodes to indirectly estimate the LEEG. It can be mainly classified into local methods, global methods, and realistic Laplacian methods. The global method is the most commonly used approach in CSD, which can achieve more accurate estimation compared with the local method, and it does not require additional imaging equipment compared with the realistic Laplacian method. CRE employs new concentric ring electrodes instead of the traditional disc electrodes, and measures the LEEG directly by differential acquisition of the multi-ring signals. Depending on the structure, it can be divided into bipolar CRE, quasi-bipolar CRE, tripolar CRE, and multi-pole CRE. The tripolar CRE is widely used due to its optimal detection performance. While ensuring the quality of signal acquisition, the complexity of its preamplifier is relatively acceptable. Here, this paper introduces the study of the SL technique in resting rhythms, visual-related potentials, movement-related potentials, and sensorimotor rhythms. These studies demonstrate that SL technology can improve signal quality and enhance signal characteristics, confirming its potential applications in neuroscientific research, disease diagnosis, visual pathway detection, and brain-computer interfaces. CSD is frequently utilized in applications such as neuroscientific research and disease detection, where high-precision estimation of LEEG is required. And CRE tends to be used in brain-computer interfaces, that have stringent requirements for real-time data processing. Finally, this paper summarizes the strengths and weaknesses of SL technology and envisages its future development. SL technology boasts advantages such as reference independence, high spatial resolution, high temporal resolution, enhanced source connectivity analysis, and noise suppression. However, it also has shortcomings that can be further improved. Theoretically, simulation experiments should be conducted to investigate the theoretical characteristics of SL technology. For CSD methods, the algorithm needs to be optimized to improve the precision of LEEG estimation, reduce dependence on the number of channels, and decrease computational complexity and time consumption. For CRE methods, the electrodes need to be designed with appropriate structures and sizes, and the low-noise, high common-mode rejection ratio preamplifier should be developed. We hope that this paper can promote the in-depth research and wide application of SL technology.


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