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.

Coronary restenosis is an important cause of poor long-term prognosis in patients with coronary heart disease. Here, we show that lysine methyltransferase SMYD2 expression in the nucleus is significantly elevated in serum- and PDGF-BB-induced vascular smooth muscle cells (VSMCs), and in tissues of carotid artery injury-induced neointimal hyperplasia. Smyd2 overexpression in VSMCs (Smyd2-vTg) facilitates, but treatment with its specific inhibitor LLY-507 or SMYD2 knockdown significantly inhibits VSMC phenotypic switching and carotid artery injury-induced neointima formation in mice. Transcriptome sequencing revealed that SMYD2 knockdown represses the expression of serum response factor (SRF) target genes and that SRF overexpression largely reverses the inhibitory effect of SMYD2 knockdown on VSMC proliferation. HDAC3 directly interacts with and deacetylates SRF, which enhances SRF transcriptional activity in VSMCs. Moreover, SMYD2 promotes HDAC3 expression via tri-methylation of H3K36 at its promoter. RGFP966, a specific inhibitor of HDAC3, not only counteracts the pro-proliferation effect of SMYD2 overexpression on VSMCs, but also inhibits carotid artery injury-induced neointima formation in mice. HDAC3 partially abolishes the inhibitory effect of SMYD2 knockdown on VSMC proliferation in a deacetylase activity-dependent manner. Our results reveal that the SMYD2-HDAC3-SRF axis constitutes a novel and critical epigenetic mechanism that regulates VSMC phenotypic switching and neointimal hyperplasia.

Objective    To predict the probability of lymph node metastasis after thoracoscopic surgery in patients with lung adenocarcinoma based on nomogram. Methods    We analyzed the clinical data of the patients with lung adenocarcinoma treated in the department of thoracic surgery of our hospital from June 2018 to May 2021. The patients were randomly divided into a training group and a validation group. The variables that may affect the lymph node metastasis of lung adenocarcinoma were screened out by univariate logistic regression, and then the clinical prediction model was constructed by multivariate logistic regression. The nomogram was used to show the model visually, the receiver operating characteristic (ROC) curve, calibration curve and clinical decision curve to evaluate the calibration degree and practicability of the model. Results    Finally 249 patients were collected, including 117 males aged 53.15±13.95 years and 132 females aged 47.36±13.10 years. There were 180 patients in the training group, and 69 patients in the validation group. There was a significant correlation between the 6 clinicopathological characteristics and lymph node metastasis of lung adenocarcinoma in the univariate logistic regression. The area under the ROC curve in the training group was 0.863, suggesting the ability to distinguish lymph node metastasis, which was confirmed in the validation group (area under the ROC curve was 0.847). The nomogram and clinical decision curve also performed well in the follow-up analysis, which proved its potential clinical value. Conclusion    This study provides a nomogram combined with clinicopathological characteristics, which can be used to predict the risk of lymph node metastasis in patients with lung adenocarcinoma with a diameter≤3 cm.

Human exhaled breath has great application prospects,e.g.,monitoring pharmacokinetics,disease diagnosis,due to its advantages such as non-invasive and high-frequency sampling.Breath samples can be collected from the oral and nasal cavity.However,the oral and nasal environment affect the chemical composition of breath sample.Therefore,the investigation on the chemical composition of mouth-exhaled breath and nose-exhaled breath is crucial for selection of appropriate sampling strategy for individual studies.In this work,secondary electrospray ionization-high resolution mass spectrometry(SESI-HRMS)was applied to analysis of respiratory metabolomics in real time.A quantitative analysis approach was established for 9 kinds of volatile organic compounds(VOCs)e.g.2-butanone,2-pentanone,ethyl acetate,methyl methacrylate,toluene,styrene,mesitylene,isoprene and limonene.The limit of detection was 2.3?240.8 ng/m3.The intra-day(n=6)and inter-day(n=18)relative standard deviations were 0.6%?4.6%and 4.3%?12.2%,respectively.Nine healthy subjects were recruited to investigate the chemical composition of mouth-exhaled and nose-exhaled breath.The results showed the good performance in quantitative analysis of 9 VOCs in breath air.It was found that the number of unique component(m/z)detected in mouth-exhaled breath(167)was 2.2 times greater than that detected in nose-exhaled breath(76),which might result from the complex environment in oral cavity.The signal intensity of commun component(163)was significantly different between mouth-exhaled breath and nose-exhaled breath.Additionally,the elemental composition analysis showed that the proportion of polar compounds detected in nose-exhaled breath was higher than that in mouth-exhaled breath.This study demonstrated that there was significant differences in the chemical composition between mouth-exhaled and nose-exhaled breath,which provided a theoretical basis for selection of exhalation mode.

Objective To comprehensively excavate and analyze the research status,research hotspots and future trends of the literature related to the field of acupoint catgut embedding therapy for pain treatment in the CNKI database.Methods We searched the CNKI database from its establishment to June 2022,and scientifically analyzed the authors,keywords,and institutions of the included literature of acupoint catgut embedding therapy for pain treatment through specific algorithms of Citespace to generate a visual knowledge map.Results A total of 319 documents were included for statistical analysis,the number of publications in the field of acupoint catgut embedding therapy for the treatment of pain was generally on the rise,the number of publications by various authors was on the low side,and there was a lack of co-operation between the research teams,with the main institutions being the Guang'anmen Hospital,Chinese Academy of Chinese Medical Sciences,Affiliated Hospital of Youjiang Medical Universities of Nationalities and the Guangzhou University of Chinese Medicine,forming a 10-keyword clustering,and the hotspots of diseases under study were mainly mixed haemorrhoids,postoperative pain,low back and leg pain and dysmenorrhoea,etc..The main interventions were pure acupoint catgut embedding therapy and the combination of acupoint catgut embedding therapy and other acupuncture therapies,and the main research method was clinical research.Conclusion Acupoint catgut embedding therapy for the treatment of pain has a good development prospect,the future needs to deepen the clinical research,strengthen the mechanism research,pay attention to the joint use of acupoint catgut embedding therapy and other traditional Chinese medicine methods,and pay attention to the research of different thread materials.

BACKGROUND:At present,the use of a locking bone plate combined with steel wire or steel cable for the treatment of periprosthetic femoral fracture often adopts monocortical fixation,which is not stable and the proximal end of the bone cannot be achieved anatomically fitted by plate.The customized anatomical plate system can effectively solve this problem. OBJECTIVE:To explore the biomechanical strength of a customized anatomical plate system in fixation of Vancouver BI periprosthetic femoral fracture. METHODS:CT thin layer scanning data of normal femurs of 1 006 cases were selected and input into the MIMICS 21.0 software to establish the three-dimensional reconstruction model of the femur,which was set as the three-dimensional reconstruction group.56 complete human femoral specimens were selected as the femoral specimen group.The measured results of the two groups for femoral anatomical appearance were compared.If there was no significant difference between the two groups,the approximate appearance of a customized anatomical plate system was designed based on the measurement results in MIMICS 21.0 software and NX11.0 software.The customized anatomical plate system was designed and prepared according to the above measurement results.Eight pairs of frozen human femurs were selected to make Vancouver BI periprosthetic femoral fracture,which of the left were thin layer scanned by dual-source CT to obtain data.The data were transferred to determine the customized anatomical plate system model by the above design software.Eight sets of customized anatomical plate systems were ultimately produced,relying on the instrument company.The eight pairs of models were numbered 1-8.The left side was fixed with the customized anatomical plate system(customized anatomical plate system group);the right side was fixed with a metal locking plate system-large locking plate(claw plate group).L1-L4 and R1-R4 were subjected to vertical short-cycle loading test and vertical loading test.L5-L8 and R5-R8 were subjected to horizontal short-cycle loading test and four-point bending test.The vertical loading test and four-point bending test were used to collect bending load,bending displacement,and bending strain.Two short cycle loading tests were used to collect strain displacement to compare the maximum load,maximum displacement,bending stiffness,and short-period displacement resistance of the two kinds of bone plates. RESULTS AND CONCLUSION:(1)There were no significant differences in all indexes between the three-dimensional reconstruction group and the femoral specimen group(P>0.05).Individual customized anatomical plate system was designed based on the measurement results combined with digital software.(2)In the vertical loading test,the maximum load was higher(P=0.015),the maximum bending displacement was smaller(P=0.014),and the bending stiffness was higher(P=0.005)in the customized anatomical plate system group compared with the claw plate group.(3)In the four-point bending test,the maximum load was higher(P=0.023),the bending stiffness was higher(P=0.005),and the maximum bending displacement was not significant(P=0.216>0.05)in the customized anatomical plate system group compared with the claw plate group.(4)In the vertical short-cycle loading test,the average level of bending displacement in the customized anatomical plate system group(0.23±0.10 mm)was significantly lower than that in the claw plate group(0.44±0.02 mm)(P<0.05).(5)There was no significant difference in the average level of bending displacement between the two groups in the horizontal short cycle loading test(P>0.05).(6)It is concluded that the customized anatomical plate system has personalized anatomical characteristics,and the fixation of Vancouver BI periprosthetic femoral fracture is more stable,which has certain significance for clinical treatment.

BACKGROUND:Interleukin-8 is an important cytokine that has been found to play an important role in bone regeneration through multiple pathways. OBJECTIVE:To comprehensively review the action mechanism of interleukin-8 effects on bone regeneration to provide ideas for the following studies on interleukin-8. METHODS:By searching the China National Knowledge Infrastructure database for articles published from January 1999 to February 2023 and PubMed database for articles published from January 1985 to February 2023 reporting the role of interleukin-8 in bone-associated cells and vascularisation.Chinese and English search terms were"interleukin-8,bone repair,bone metabolism,mesenchymal stem cells,osteoblasts,osteoclasts,vascularization".The initial review yielded 508 articles in English and Chinese,and a total of 51 articles were included for review and analysis according to the inclusion and exclusion criteria. RESULTS AND CONCLUSION:According to the existing research,interleukin-8 can promote bone cell regeneration and assist bone healing through multiple pathways,which is mainly divided into three aspects:(1)Promote the proliferation and differentiation of bone cells such as mesenchymal stem cells and osteoblasts,and promote the development of cells in the direction of promoting bone healing;(2)interleukin-8 can promote angiogenesis and provide sufficient nutrition and oxygen for bone tissue,thus further improving the quality and stability of bone healing.(3)The appearance of interleukin-8 facilitates the expression of hypoxia-inducible factor-1α,vascular endothelial growth factor,and matrix metalloproteinase,which can create a microenvironment conducive to bone regeneration,thus promoting the regeneration and repair of bone tissue.In summary,interleukin-8 plays an important role in bone healing by promoting osteoblast proliferation and differentiation,facilitating angiogenesis and improving the mechanical properties of bone regeneration,as well as influencing bone metabolism through osteoclasts,mesenchymal stem cells,and other action sites.