Although global brain science research has progressed rapidly in recent decades, several fundamental questions in neuroscience remain unresolved. In particular, the physical mechanism underlying neural signal transmission remains controversial, and the carriers responsible for neural information storage and retrieval have not yet been fully clarified. These unresolved issues motivate us to re-examine the processes of neural information generation, transmission, integration, storage, and retrieval from multiple perspectives. A key observation is that neural electromagnetic activities are closely associated with time. Their duration, temporal structure, and dynamic evolution play crucial roles in neural information processing. In this work, we analyze neural electromagnetic activities from the perspective of temporal scales (referred to here as the “time course”). By reviewing and integrating findings from previous studies, we examine the characteristic time requirements and dynamic features of neural processes occurring at different stages of information processing. These stages include neural signal generation, signal transmission along axons, synaptic integration, synaptic plasticity, and memory formation and retrieval. Based on this temporal analysis, we outline a framework describing neural electromagnetic activities across a wide range of time scales, spanning from microseconds to minutes, hours, or even longer periods associated with long-term memory, which suggests that neural information processing involves multiple physical processes operating at different time levels. Rapid electromagnetic events may occur on microsecond scales, whereas electrophysiological phenomena such as action potentials typically last on the order of milliseconds. Longer time scales are associated with synaptic plasticity and memory-related processes. From this perspective, we propose that the physical carrier of neural information may be transient electromagnetic pulses with durations on the microsecond scale. In this framework, action potentials can be interpreted as the macroscopic electrophysiological manifestation of underlying electromagnetic processes triggered by ionic currents across neuronal membranes. Rather than being the fundamental neural signal itself, the action potential may represent a measurable membrane-level response associated with the successful activation of these electromagnetic events. Moreover, we discuss a possible mechanism for long-term memory storage. Considering the apparent temporal contradiction between the millisecond-scale excitation of neurons and the long-term persistence of memories, we believe that long-term memory information may be stored within neural network topologies formed by electrical synapse coupling. Such structures, referred to as electrically coupled memory networks (ECMNs), may enable neurons within the same network to respond rapidly and synchronously to stimuli, thereby facilitating efficient memory retrieval. Overall, this study emphasizes the importance of considering the temporal organization of neural electromagnetic activities when interpreting neural signaling mechanisms. It may provide new insights into the physical nature of neural information carriers and the mechanisms of memory storage and retrieval. Furthermore, highlighting the potential role of electromagnetic interactions in neural activity may contribute to the development of new theoretical frameworks and experimental approaches in neuroscience. Such perspectives may also offer valuable references for future research on neural coding, brain function mechanisms, and neuromodulation technologies.

Objective To explore the characteristics and correlation between perivascular spaces (PVS) and diffusion tensor image analysis along perivascular spaces (DTI-ALPS) index in patients with amnestic mild cognitive impairment (aMCI). Methods A retrospective study was conducted on a total of 118 participants, including cognitive normal (CN) healthy controls and aMCI patients, recruited from the Department of Neurology, Zhongshan Hospital, Fudan University from September 2020 to September 2022. All participants underwent structural magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI). An automatic segmentation algorithm was used to quantify PVS metrics in the brain, and DTI-ALPS index was calculated based on DTI. Differences in DTI-ALPS index and PVS metrics between the CN and aMCI groups were compared. Multivariate logistic regression was used to identify independent factors influencing aMCI. Correlation analysis was performed to assess relationships among DTI-ALPS index, PVS metrics, and cognitive scores. Results A total of 80 CN healthy controls and 38 aMCI patients were included. The DTI-ALPS index was significantly lower in the aMCI group compared with the CN group (1.28±0.18 vs 1.37±0.21, P＝0.018), while differences in PVS metrics between groups were not statistically significant. Multivariate logistic regression analysis indicated that DTI-ALPS index was an independent factor affecting aMCI (OR＝0.097, 95%CI 0.011–0.833, P＝0.033). Correlation analysis revealed a positive relationship between DTI-ALPS index and MMSE score (r＝0.210, P＝0.023) as well as PVS length in the centrum semiovale (r＝0.216, P＝0.019). Conclusions The DTI-ALPS index may serve as an imaging biomarker for identifying early cognitive impairment, and patients with aMCI exhibit abnormal DTI-ALPS indices, suggesting that brain glymphatic system dysfunction may occur prior to morphological changes.

OBJECTIVE To compare the efficacy and safety of infliximab（IFX）， ustekinumab（UST） and vedolizumab（VDZ） in the treatment of active Crohn’s disease （CD）. METHODS The patients with active CD who were diagnosed and initially received any of the aforementioned biologics at the First Affiliated Hospital of the USTC （Anhui Provincial Hospital） from January 2020 to December 2023 were selected as the study subjects. They were divided into the IFX group （34 cases）， the UST group （37 cases）， and the VDZ group （15 cases） based on their treatment regimens. Patients in all three groups received induction and maintenance therapy with IFX， UST or VDZ for at least 12 months. The CD Activity Index （CDAI） scores and their changes from baseline （ΔCDAI）， clinical remission rates， clinical response rates， nutritional indicators [body mass index （BMI）， albumin （ALB）， hemoglobin （HGB）]， and inflammatory markers [C-reactive protein （CRP）， erythrocyte sedimentation rate （ESR）] of three groups after the induction phase （9th week of treatment） and during the maintenance phase （12th month of treatment） were compared. Additionally， the cumulative clinical remission rates at 1 year of treatment and the incidence of adverse events （AEs） were compared. RESULTS There were no statistically significant differences in the aforementioned baseline indicators among the three groups （ P ＞0.05）. In all three groups， the CDAI scores were significantly lower after the induction phase and during the maintenance phase， compared to the baseline （ P ＜0.05）. In the IFX group， CDAI scores at the above time points were significantly lower than those in the UST and VDZ groups during the same periods （ P ＜0.05）， and the absolute value of ΔCDAI during the maintenance phase was significantly higher than that in the VDZ group （ P ＜0.05）. The clinical remission rate in the IFX group during the maintenance phase was significantly higher than that in the UST and VDZ groups during the same period， and the clinical response rate was significantly higher than that in the VDZ group during the same period （ P ＜0.05）. The levels of ALB， HGB， CRP and ESR in the IFX group after the induction phase and during the maintenance phase， as well as the levels of CRP and ESR in the UST group after the induction phase， all improved significantly compared to the baseline. Furthermore， the levels of ALB and HGB in the IFX group were significantly higher than those in the UST and VDZ groups during the same period （ P ＜0.05）. The cumulative clinical remission rates among the three groups were significantly different （ P ＜0.05）， with patients in the IFX group achieving remission more rapidly and at a higher proportion. There was no statistically significant difference in the incidence of AEs among IFX， UST and VDZ groups （14.71%， 8.11% and 20.00%， respectively； P ＞0.05）； infusion reactions were the most common AEs in the IFX group （8.82%）. CONCLUSIONS Compared with UST and VDZ， IFX demonstrates a higher clinical remission rate during the maintenance phase， more effectively improves active CD patients’ nutritional status， and continuously reduces systemic inflammatory responses. However， clinicians should be mindful of the risk of adverse events， such as infusion reactions， associated with this drug.

ObjectiveTo evaluate the effect of action observation therapy (AOT) combined with low-frequency repetitive transcranial magnetic stimulation (rTMS) on post-stroke unilateral spatial neglect. MethodsA total of 108 patients with post-stroke unilateral spatial neglect admitted to Suqian Integrated Traditional Chinese and Western Medicine Hospital from January, 2023 to March, 2024 were enrolled. The patients were randomly allocated to AOT group, rTMS group and combined group with 36 patients in each group. All the groups received conventional treatment. The AOT group additionally received AOT, the rTMS group additionally received rTMS, and the combined group received both AOT and rTMS, for four weeks. Before and after treatment, the patients were assessed using the Montreal Cognitive Assessment (MoCA), Fugl-Meyer Assessment (FMA), modified Barthel Index (MBI), Chinese Behavioural Inattention Test-conventional test (CBIT-C) and CBIT-behavioural test (CBIT-B). The latency and amplitude of the N20 potential on the affected side were also measured. ResultsThree patients dropped out from each group. After intervention, significant main effects of time (F > 77.096, P < 0.001) and group (F > 5.119, P < 0.01) and significant time-by-group interaction effects (F > 3.320, P < 0.05)were observed in the MoCA, FMA, MBI, and CBIT-C scores. For the CBIT-B score, the main effects of time (F = 367.430, P < 0.001) and group (F = 4.995, P = 0.008) were significant. After intervention, MoCA, FMA, MBI, CBIT-C and CBIT-B scores, and N20 amplitude and latency were better in the combined group than in the AOT and rTMS groups (P < 0.05). ConclusionThe combination of AOT and rTMS may further ameliorate cognitive function, motor function, activities of daily living, and the degree of spatial neglect in post-stroke patients with unilateral spatial neglect, potentially attributable to improved nerve conduction function.

With the rapid advancement of medical technology and the increasing complexity of clinical environments, competence in clinical ethical decision-making has become an indispensable core competency for exemplary physicians. However, traditional medical ethics education has long been confronted with the persistent challenges of theory-practice dissociation and the disconnect between pedagogical settings and clinical realities. Thus, how to construct a "Clinical Ethics" curriculum that aligns with the objectives of training high-caliber medical professionals has emerged as a critical and challenging issue in current medical education reform. To effectively address this challenge, the Office of Education at Peking University Third Hospital, since 2021, has assembled a multidisciplinary "Clinical Ethics" teaching and management team comprising faculty from Peking University School of Humanities and key clinical specialists from the hospital. In 2022, the "Clinical Ethics" elective course was formally launched for fourth-year students in the eight-year MD program who had completed coursework in "Medical Ethics" and organ-system-based curricula, with the aim of exploring and operationalizing a pre-clinical ethics education model tailored for senior medical students. The course employs a modular instructional design encompassing "theoretical review-case-based deliberation-clinical workshop", which effectively facilitates the deep integration of medical humanities with clinical practice.Following four years of iterative refinement through the "plan-act-observe-reflect" cycle, the course has demonstrated positive outcomes in enhancing students' ethical awareness and decision-making capabilities, and has preliminarily established a sustainable collaborative mechanism among the multidisciplinary faculty team. This article systematically delineates the course development background, pedagogical model and methodological innovations, and the multidisciplinary collaborative framework, alongside reflections and summaries based on implementation outcomes, with the intent of providing references for the future development of "Clinical Ethics" curricula.

In cases where a tracheal injury exceeds half the length of the adult trachea or one-third of the length of the child trachea, it becomes difficult to perform end-to-end anastomosis after tracheal resection due to excessive tension at the anastomosis site. In such cases, tracheal replacement therapy is required. Advances in tissue engineering technology have led to the development of tissue engineering tracheal substitutes, which have promising applications. Hydrogels, which are highly hydrated and possess a good three-dimensional network structure, biocompatibility, low immunogenicity, biodegradability, and modifiability, have had wide applications in the field of tissue engineering. This article provides a review of the characteristics, advantages, disadvantages, and effects of various hydrogels commonly used in tissue engineering trachea in recent years. Additionally, the article discusses and offers prospects for the future application of hydrogels in the field of tissue engineering trachea.

This comprehensive review synthesizes the latest advancements in understanding inflammatory disorders affecting cerebral small vessels, a distinct yet understudied category within cerebral small vessel diseases (SVD). Unlike classical SVD, these inflammatory conditions exhibit unique clinical presentations, imaging patterns, and pathophysiological mechanisms, posing significant diagnostic and therapeutic challenges. Highlighting their heterogeneity, this review spans primary angiitis of the central nervous system, cerebral amyloid angiopathy-related inflammation, systemic vasculitis, secondary vasculitis, and vasculitis in autoinflammatory diseases. Key discussions focus on emerging insights into immune-mediated processes, neuroimaging characteristics, and histopathological distinctions. Furthermore, this review underscores the importance of standardized diagnostic frameworks, individualized immunomodulation approaches, and novel targeted therapies to address unmet clinical demands.
Humans ; Cerebral Small Vessel Diseases/pathology* ; Inflammation/pathology* ; Cerebral Amyloid Angiopathy/pathology* ; Vasculitis, Central Nervous System/pathology* ; Vasculitis/pathology*

Processing for deodorization is widely used in the production of animal-derived Chinese medicinal materials. In this study, Heracles Neo ultra-fast gas-phase electronic nose combined with chemometrics was employed to analyze the overall odor difference of Cervi Cornu Pantotrichum(focusing on that derived from Cervus nippon Temminck in this study) before and after processing. The results showed that the electronic nose effectively distinguished between the medicinal materials and decoction pieces of Cervi Cornu Pantotrichum. HS-GC-MS was used to identify and quantify the volatile components in the medicinal materials and decoction pieces of Cervi Cornu Pantotrichum, and 35 and 37 volatile components were detected in the medicinal materials and decoction pieces, respectively. The medicinal materials and decoction pieces contained 28 common volatile components contributing to the odor of Cervi Cornu Pantotrichum. The odor activity value(OAV) of each volatile component was calculated based on the olfactory threshold and relative content. The results showed that there were 17 key odor substances such as isovaleraldehyde, 2-methylbutanal, isobutyraldehyde, hexanal, and methanethiol in the medicinal materials and decoction pieces of Cervi Cornu Pantotrichum. All of them had bad odor and were the main source of the odor of Cervi Cornu Pantotrichum. The results of principal component analysis(PCA) and orthogonal partial least squares-discriminant analysis(OPLS-DA) showed that there were significant differences in volatile components between the medicinal materials and decoction pieces of Cervi Cornu Pantotrichum. Based on the thresholds of P<0.05 and Variable Importance in Projection(VIP)>1, 21 differential volatile odor components were screened out. Among them, isopentanol, isovaleraldehyde, 2-methylbutanal, n-nonanal, and dimethylamine were the key differential odor compounds between the medicinal materials and decoction pieces of Cervi Cornu Pantotrichum. The odor compounds and their relative content reduced, and some flavor substances such as esters were produced after processing with wine, which was the main reason for the reduction of the odor after processing of Cervi Cornu Pantotrichum.
Odorants/analysis* ; Electronic Nose ; Gas Chromatography-Mass Spectrometry/methods* ; Animals ; Volatile Organic Compounds/analysis* ; Deer ; Drugs, Chinese Herbal/chemistry*

The therapeutic effects of traditional Chinese medicine(TCM) decoction is closely related to its decocting methods. A correct understanding of the scientific connotations of decocting methods in TCM is of great significance for guiding the application of decoctions and the development of modern TCM preparations based on decoctions. The decocting process is not only a hot water extraction process of chemical components but also accompanied by complex chemical and physical changes, forming a complex multiphase system and significantly affecting the absorption and therapeutic effect of TCM. This article reviews the research progress in scientific connotations of decocting methods in TCM from the perspectives of chemical composition changes, phase state differences,absorption behavior changes, and pharmacological and toxicological changes caused by decocting. This review is expected to provide implications for studying decocting methods and their scientific interpretation, boost the innovation and development of TCM decoctions,and promote the design and development of modern TCM preparations.
Drugs, Chinese Herbal/isolation & purification* ; Humans ; Medicine, Chinese Traditional/methods* ; Animals

OBJECTIVE: To explore the effectiveness of artificial hemi-knee prosthesis reconstruction for bone defects after resection of pediatric osteosarcoma. METHODS: A retrospective analysis was conducted on the clinical data of 18 children with osteosarcoma who met the selection criteria and were treated between January 2016 and December 2019. There were 11 males and 7 females, aged 6-10 years (mean, 8.9 years). Osteosarcoma located in the distal femur in 11 cases and the proximal tibia in 7 cases. Among them, 12 cases were conventional osteosarcoma and 6 cases were small cell osteosarcoma, with a disease duration of 1-9 months (mean, 3.1 months). All patients received 2 cycles of preoperative chemotherapy with doxorubicin, cisplatin, and ifosfamide. After en bloc tumor segment resection, bone defects were reconstructed using custom-made artificial hemi-knee prostheses. Rehabilitation training was initiated at 8 weeks postoperatively under the protection of a knee immobilizer brace, combined with 4 cycles of adjuvant chemotherapy. During follow-up, lower limb growth length and limb shortening (compared with the healthy side) were measured, and limb function was evaluated using the Musculoskeletal Tumor Society-93 (MSTS-93) scoring system. RESULTS: All surgeries were successfully completed, with an operation time of 2.0-3.1 hours (mean, 2.4 hours) and intraoperative blood loss of 180-320 mL (mean, 230.0 mL). Incisional edge necrosis occurred in 1 case at 10 days postoperatively, while the incisions of the remaining 17 patients healed by first intention. One case developed periprosthetic infection caused by Staphylococcus aureus at 1 week postoperatively, which was cured after symptomatic treatment. All 18 patients were followed up 60-96 months (mean, 74.2 months). No local tumor recurrence was observed during follow-up. Imaging examinations showed prosthesis loosening in 2 cases, while the prosthesis of other patients were well-positioned. At last follow-up, the knee joint range of motion was 80°-120° (mean, 106.7°). The MSTS-93 score was 16-29 (mean, 24.7), with 12 cases rated as excellent, 5 good, and 1 fair. The patients' height increased by 12.8-20.0 cm (mean, 15.5 cm), the lower limb growth length was 6.0-13.0 cm (mean, 9.7 cm), and limb shortening was 1.8-4.6 cm (mean, 3.1 cm). There was no significant difference in MSTS-93 scores, lower limb growth length, or limb shortening between the distal femur group and the proximal tibia group ( P>0.05). CONCLUSION Artificial hemi-knee prosthesis reconstruction can preserve the adjacent normal epiphysis of the knee joint, maximize limb growth potential, and reduce adult limb length discrepancy, making it a suitable reconstruction option for children with knee osteosarcoma.
Humans ; Osteosarcoma/surgery* ; Male ; Child ; Female ; Knee Prosthesis ; Retrospective Studies ; Bone Neoplasms/surgery* ; Plastic Surgery Procedures/methods* ; Tibia/surgery* ; Femur/surgery* ; Arthroplasty, Replacement, Knee/methods* ; Treatment Outcome ; Chemotherapy, Adjuvant ; Femoral Neoplasms/surgery*