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.

Psoraleae Fructus is derived from the dried fruit of the Psoralea corylifolia L. It has the effects of tonifying the kidney, strengthening the Yang, warming the spleen and stopping diarrhea, and is used for the treatment of kidney deficiency and impotence, lumbar soreness and cold pain, osteoporosis and other diseases, and it is a commonly used tonic traditional Chinese medicine in Chinese medicine clinics in China. However, in recent years, the clinical adverse reactions of Psoraleae Fructus (PF) and related preparations have been increasingly reported, especially hepatotoxicity, which has become a bottleneck in the clinical application of PF and associated preparations. The safety of PF was rarely recorded in ancient texts, but modern clinical and experimental research has shown that PF not only has direct toxicity but also has immune-idiosyncratic toxicity. For this reason, this study comprehensively analyzes the evolution of PF effect/toxicity records in ancient and modern canonical literature, and combines with the progress of modern pharmacology and toxicology research, to conduct an in-depth discussion on the clinical characteristics, causative mechanisms and risk factors of PF hepatotoxicity. On this basis, based on the three-dimensional "human-medicine-use" precise prevention and control strategy for the safety risk of traditional Chinese medicine proposed by the author's team, safety risk prevention and control measures for PF and related preparations were developed, aiming at guiding the safe and rational use of PF and related preparations in the clinic and promoting the healthy and sustainable development of PF-related industries.

Oral diseases concern almost every individual and are a serious health risk to the popula-tion.The restorative treatment of tooth and jaw defects is an important means to achieve oral function and support the appearance of the contour.Based on the principle of"learning from the nature",Deng Xu-liang's group of Peking University School and Hospital of Stomatology has proposed a new concept of"microstructural biomimetic design and tissue adaptation of tooth/jaw materials"to address the worldwide problems of difficulty in treating dentine hypersensitivity,poor prognosis of restoration of tooth defects,and vertical bone augmentation of alveolar bone after tooth loss.The group has broken through the bottle-neck of multi-stage biomimetic technology from the design of microscopic features to the enhancement of macroscopic effects,and invented key technologies such as crystalline/amorphous multi-level assembly,ion-transportation blocking,and multi-physical properties of the micro-environment reconstruction,etc.The group also pioneered the cationic-hydrogel desensitizer,digital stump and core integrated restora-tions,and developed new crown and bridge restorative materials,gradient functionalisation guided tissue regeneration membrane,and electrically responsive alveolar bone augmentation restorative membranes,etc.These products have established new clinical strategies for tooth/jaw defect repair and achieved inno-vative results.In conclusion,the research results of our group have strongly supported the theoretical im-provement of stomatology,developed the technical system of oral hard tissue restoration,innovated the clinical treatment strategy,and led the progress of the stomatology industry.

BACKGROUND:Early postural adjustments serve as preparatory measures for forthcoming actions or potential disruptions in posture,thereby facilitating improved movement execution and mitigating destabilizing effects caused by posture interference. OBJECTIVE:To investigate the characteristics of temporal and intensity parameters of key lower limb muscles during early postural adjustment phase when stroke patients with varying levels of balance initiate walking at a self-selected comfortable pace. METHODS:The characteristics of early postural adjustments in 16 stroke patients were observed.Sixteen patients were divided into a non-fall group(n=8)and a fall group(n=8)based on the history of falls and Berg Balance Scale scores.Noraxon inertial sensors and Noraxon Ultium EMG wireless surface electromyography were utilized to collect body kinematic data and surface electromyography data during gait initiation.Muscle activation time and activation sequence of six key muscles in the lower limbs(tibialis anterior,medial and lateral gastrocnemius,rectus femoris,lateral femoris and biceps femoris muscles)during the early postural adjustment phase,as well as normalized electromyography integral values for the four time windows(each 150 ms)before gait initiation,were analyzed. RESULTS AND CONCLUSION:Stroke patients with a history of falls exhibited earlier activation times for the six key muscles in the lower limbs during gait initiation compared with those in the non-fall group.The fall group demonstrated significantly earlier activation times for tibialis anterior,lateral head of gastrocnemius,and vastus lateralis(P<0.01,P<0.05).In contrast,the non-fall group displayed a consistent pattern of activating extensor muscles before flexor muscles,with thigh muscle activation preceding calf muscle activation.However,in the fall group,calf extensor muscle activation occurred prior to thigh extensor muscle activation,and the vastus lateralis was activated even earlier.The tibialis anterior was the last activated muscle in both groups.Specifically during T3(>-300 to-150 ms),the tibialis anterior exhibited significantly higher activity in the fall group compared with the non-fall group(P<0.05),while the lateral head of gastrocnemius demonstrated significant inhibition during T3(P<0.05)and the medial head of gastrocnemius showed significant inhibition during both T3 and T4(>-150 to 0 ms)stages compared with the non-fall group(P<0.01,P<0.05).To conclude,stroke patients with varying balance abilities employ distinct early postural adjustment strategies prior to stepping,as evidenced by differences in muscle activation timing,recruitment order,and muscle activity amplitude.Patients at a high risk of falling exhibit prolonged duration of early postural adjustment and delayed initiation of gait,indicating earlier activation of the tibialis anterior muscle and inhibition of gastrocnemius muscle activity.These delays in gait initiation and variations in muscle recruitment strategies may contribute to unstable posture and an increased susceptibility to falls.

Objective To summarize the epidemiological and clinical features of infectious diseases of the central nervous system(CNS)by a single-center analysis.Methods A retrospective analysis was conducted on the data of 1247 cases of CNS infectious diseases diagnosed and treated in the First Medical Center of PLA General Hospital from 2001 to 2020.Results The data for this group of CNS infectious diseases by disease type in descending order of number of cases were viruses 743(59.6％),Mycobacterium tuberculosis 249(20.0％),other bacteria 150(12.0％),fungi 68(5.5％),parasites 18(1.4％),Treponema pallidum 18(1.4％)and rickettsia 1(0.1％).The number of cases increased by 177 cases(33.1％)in the latter 10 years compared to the previous 10 years(P<0.05).No significant difference in seasonal distribution pattern of data between disease types(P>0.05).Male to female ratio is 1.87︰1,mostly under 60 years of age.Viruses are more likely to infect students,most often at university/college level and above,farmers are overrepresented among bacteria and Mycobacterium tuberculosis,and more infections of Treponema pallidum in workers.CNS infectious diseases are characterized by fever,headache and signs of meningeal irritation,with the adductor nerve being the more commonly involved cranial nerve.Matagenomic next-generation sequencing improves clinical diagnostic capabilities.The median hospital days for CNS infectious diseases are 18.00(11.00,27.00)and median hospital costs are ￥29,500(￥16,000,￥59,200).The mortality rate from CNS infectious diseases is 1.6％.Conclusions The incidence of CNS infectious diseases is increasing last ten years,with complex clinical presentation,severe symptoms and poor prognosis.Early and accurate diagnosis and standardized clinical treatment can significantly reduce the morbidity and mortality rate and ease the burden of disease.

Objective To investigate the role of dynamin-related protein 1(Drp-1)and peroxisome proliferator-activated receptor γ coactivator 1-α(PGC-1α)in the lung tissues of neonatal rats with meconium aspiration syndrome(MAS)and its mechanism.Methods Fifty 2-3-week-old SD neonatal rats were randomly divided into five groups(n=10):control group,model group and SN50 low,medium and high concentration groups.In control group,2 ml/kg of saline was injected into the trachea after tracheal exposure,and 2 ml/kg of meconium suspension was injected into the trachea of the rest of groups;after 24 h,control and model groups were left untreated,and 100 μl of each of SN50 concentrations of 10,30,and 60 μg/ml was injected into SN50 low,medium,and high concentration groups intraperitoneally;the rats of each group were killed after 6 h,and the chest X-rays,the gross views of the lungs,the lung wet/dry weight ratios(W/D),and the lungs of the rats in control group and model group were examined.After 6 h,the rats in each group were executed,and the pathological changes of lung tissue were observed by chest radiographs,lung gross view,lung wet/dry weight ratio(W/D)and HE staining;Western blotting was used to detect the changes of nuclear factor κB(NF-κB)(p65),p-NF-κB p65(p-p65),Drp-1,and PGC-1α proteins expression in neonatal rat lung tissues,and immuno-histochemistry was used to observe the expression of p65,Drp-1,and PGC-1α related proteins expression in neonatal rat lung tissues.Results Compared with control group,model group showed inflammatory infiltration in the chest radiograph and gross view,and the W/D and lung injury pathology scores were significantly higher(P＜0.05);compared with model group,the chest radiograph and gross view of inflammation were slightly reduced in SN50 low,medium and high concentration groups,and the W/D and lung injury pathology scores were significantly lower(P＜0.05).Western blotting showed that,compared with control group,the protein expression levels of p-p65 and Drp-1 in the lung tissues of neonatal rats were significantly higher in model group(P＜0.05),and the protein expression level of PGC-1α was significantly lower(P＜0.05);compared with model group,the protein expression levels of p-p65 and Drp-1 were significantly lower in SN50 low,medium,and high concentration groups(P＜0.05),and the difference in the protein expression level of PGC-1α in SN50 low concentration group was not statistically significant(P＞0.05),whereas the PGC-1α expression levels in SN50 medium and high concentration groups were significantly higher(P＜0.05);the difference in the total p65 protein expression levels in each group was not statistically significant(P＞0.05).Immunohistochemical assay results showed that,compared with control group,p65 and Drp-1 protein expression levels were significantly higher in model group(P＜0.05),and PGC-1α protein expression level was significantly lower(P＜0.05);compared with model group,p65 protein expression level was significantly lower in SN50 low concentration group(P＜0.05),and the difference in Drp-1 and PGC-1α protein expression levels were not statistically significant(P＞0.05),Drp-1 protein expression level was significantly lower(P＜0.05),and PGC-1α protein expression level was significantly higher(P＜0.05)in SN50 middle and high concentration groups.Conclusion Fecal inhalation can induce lung tissue inflammation in neonatal rats,and the mechanism may be related to enhanced oxidative stress,promotion of mitochondrial dysfunction,activation of the Drp-1/NF-κB signaling pathway,and inhibition of PGC-1α protein expression.

Objective To compare the pharmacokinetic profiles of the two teriflunomide tablets in healthy Chinese subjects under fasting and fed conditions and to evaluate their bioequivalence and safety.Methods A randomized,open,single-dose,parallel trial design was used to enroll 31 and 32 healthy Chinese male subjects in the fasting and fed groups,who were randomized to a single oral dose of 14 mg of either reference or test preparation of teriflunomide tablets.The plasma concentrations of teriflunomide were determined using liquid chromatography-tandem mass spectrometry method,and Phoenix WinNonlin 8.1 software was used to calculate pharmacokinetic parameters and perform bioequivalence analysis.Results Subjects received a single oral dose of the reference and test formulations of teriflunomide.The main pharmacokinetic parameters of teriflunomide in the fasting group were as follows:Cmax were(2.14±0.27)and(2.27±0.33)μg·mL-1,AUC0-72h were(105.70±11.20)and(107.72±11.77)μg·mL-1·h,tmax was 1.49 and 0.99 h;the main pharmacokinetic parameters of teriflunomide in the fed group were as follows:Cmaxwere(1.83±0.17)and(1.75±0.22)μg·mL-1,AUC0-72h were(102.66±9.18)and(101.57±13.01)μg·mL-1·h,tmax was 4.01 and 4.99 h.The 90％confidence intervals for the geometric means of Cmax and AUC0-72h for reference and test preparations in the fasting and fed groups were in the range of 80％to 125％.Conclusion The pharmacokinetic characteristics of the 2 formulations were similar under fasting and fed administration conditions,with good bioequivalence and safety;Postprandial administration may delay the time to peak of the drug.