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 in vitro and in vivo inhibitory effects and mechanism of metformin on the malignant biological behavior of esophageal squamous cell carcinoma （ESCC） cells by the hypoxia inducible factor-1α （HIF-1α）/interleukin-8 （IL-8） signaling pathway. METHODS Human ESCC TE1 cells were assigned into blank group， metformin low-， medium-， and high-dose groups （0.5， 1， 2 mmol/L）， IDF-11774 （HIF-1α inhibitor） group （20 μmol/L）， and high-dose metformin+HIF-1α activator dimethyloxalylglycine （DMOG） group. After 24 h treatment， cell proliferation [measured by the positive rate of 5-ethynyl- 2′-deoxyuridine （EdU） and optical density at 450 nm （OD450 value）]， apoptosis， invasion and migration as well as mRNA expressions of proliferating cell nuclear antigen （PCNA）， Bcl-2 interacting mediator of cell death （Bim）， migration and invasion enhancer 1 （MIEN1）， and matrix metalloproteinase-9 （MMP-9）， and protein expressions of HIF-1α and IL-8 in the cells were detected. The xenograft tumor model of nude mice was established. Thirty nude mice were randomly divided into blank group， metformin low-， medium-， and high-dose groups （i.g. administration of metformin 62.5， 125， 250 mg/kg+i.p. administration of equal volume of normal saline）， IDF-11774 group （i.g. administration of 50 mg/kg IDF-11774+i.p. administration of equal volume of normal saline） and high-dose metformin+DMOG group （i.g. administration of metformin 250 mg/kg+i.p. administration of DMOG 250 mg/kg）， with 5 mice in each group. They were given relevant medicine， once a day， for 4 consecutive weeks； the mass and volume of the tumor and protein expressions of HIF-1α and IL-8 in the tumor tissue were determined. RESULTS The EdU positive rate， OD450 value， cell invasion number， scratch healing rate， mRNA expressions of PCNA， MIEN1 and MMP-9， protein expressions of HIF-1α and IL-8， as well as the mass and volume of transplanted tumors and protein expressions of HIF-1α and IL-8 in tumor tissues were decreased by metformin in concentration/dose-dependent manner （P＜0.05）. Additionally，metformin increased the apoptosis rate and mRNA expression of Bim in cells （P＜0.05）. The trend of changes in corresponding indicators in the IDF-11774 group was consistent with that in the metformin groups， whereas DMOG could significantly attenuate the aforementioned effects of high-concentration/high-dose metformin （P＜0.05）. CONCLUSIONS Metformin can inhibit the proliferation， invasion， migration of TE1 cells， and tumor growth of nude mice， and induce cell apoptosis， the mechanism of which may be related to the inhibition of HIF-1α/IL-8 signaling pathway.

Metachromatic leukodystrophy (MLD) is an inherited disease caused by a deficiency of the enzyme arylsulfatase A (ARSA). Lentivirus-modified autologous hematopoietic stem cell gene therapy (HSCGT) has recently been approved for clinical use in pre and early symptomatic children with MLD to increase ARSA activity. Unfortunately, this advanced therapy is not available for most patients with MLD who have progressed to more advanced symptomatic stages at diagnosis. Patients with late-onset juvenile MLD typically present with a slower neurological progression of symptoms and represent a significant burden to the economy and healthcare system, whereas those with early onset infantile MLD die within a few years of symptom onset. We conducted a pilot study to determine the safety and benefit of HSCGT in patients with postsymptomatic juvenile MLD and report preliminary results. The safety profile of HSCGT was favorable in this long-term follow-up over 9 years. The most common adverse events (AEs) within 2 months of HSCGT were related to busulfan conditioning, and all AEs resolved. No HSCGT-related AEs and no evidence of distorted hematopoietic differentiation during long-term follow-up for up to 9.6 years. Importantly, to date, patients have maintained remarkably improved ARSA activity with a stable disease state, including increased Functional Independence Measure (FIM) score and decreased magnetic resonance imaging (MRI) lesion score. This long-term follow-up pilot study suggests that HSCGT is safe and provides clinical benefit to patients with postsymptomatic juvenile MLD.
Humans ; Leukodystrophy, Metachromatic/genetics* ; Pilot Projects ; Genetic Therapy/methods* ; Hematopoietic Stem Cell Transplantation ; Male ; Follow-Up Studies ; Female ; Lentivirus/genetics* ; Child ; Child, Preschool ; Hematopoietic Stem Cells/metabolism* ; Cerebroside-Sulfatase/metabolism* ; Adolescent

The triterpenoid saponins of Centella asiatica, including asiaticoside, madecassoside, asiatic acid, and madecassic acid, are pivotal bioactive compounds of the plant. These constituents exhibit a spectrum of pharmacological activities, such as antioxidant, antitumor, and antidepressant effects, promotion of wound healing, and enhancement of microcirculation. Owing to these therapeutic properties, C. asiatica is widely employed in pharmaceutical and cosmetic industries. However, the escalating global demand for its extracts has led to potential supply shortages, prompting researchers to use multiple strategies such as multi-omics, molecular biology, and synthetic biology to conduct extensive studies. These studies encompass the elucidation of the biosynthetic pathways of triterpenoid saponins in C. asiatica, metabolic regulation, the hormonal induction of secondary metabolite synthesis, and the application of biotechnological strategies for natural product production to increase the yield of secondary metabolites in C. asiatica, or to produce active components via microbial chassis, thus satisfying market demands and promoting the sustainable exploitation of wild C. asiatica resources. This article first introduced the triterpenoid saponins of C. asiatica and their biological activities, then summarized the latest research advancements in their biosynthetic pathways, metabolic regulation, and heterologous biosynthesis, and provided an outlook on future development directions, with the aim of providing reference for comprehensive resource development and biotechnological synthesis of active components from C. asiatica.
Centella/genetics* ; Triterpenes/chemistry* ; Biosynthetic Pathways ; Humans ; Drugs, Chinese Herbal/chemistry* ; Plant Extracts

OBJECTIVES: To summarize the clinical and genetic characteristics of epilepsy with intellectual disability caused by SETD1B gene variants in children. METHODS: A retrospective analysis was conducted on the clinical data of three children with SETD1B gene variants diagnosed and treated at the Department of Pediatric Neurology of Xiangya Hospital of Central South University. Relevant literature was reviewed to summarize the clinical characteristics of this condition. RESULTS: All three children presented with symptoms during infancy or early childhood, including mild intellectual disability and myoclonic seizures, with two cases exhibiting eyelid myoclonia. After treatment with three or more antiepileptic drugs, two cases achieved seizure control or partial control, while one case remained refractory. Each of the three children was found to have a heterozygous variant in the SETD1B gene (one deletion, one frameshift, and one missense variant). To date, 54 cases with SETD1B gene variants have been reported, involving a total of 56 variants, predominantly missense variants (64%, 36/56). The main clinical manifestations included varying degrees of developmental delay (96%, 52/54) and seizures (81%, 44/54). Among the 44 patients with seizures, myoclonic (20%, 9/44) and absence seizures (34%, 15/44) were common, with eyelid myoclonia reported in six cases. Approximately one-fifth of these patients had poorly controlled seizures. CONCLUSIONS The primary phenotypes associated with SETD1B gene variants are intellectual disability and seizures, and seizures exhibit distinct characteristics. Eyelid myoclonia is not uncommon.
Humans ; Intellectual Disability/complications* ; Epilepsy/complications* ; Male ; Female ; Histone-Lysine N-Methyltransferase/genetics* ; Child, Preschool ; Child ; Retrospective Studies

Arsenic is a semi-metal,and lipid-soluble arsenic compounds are one of the widespread forms in the environment and food chain,but there is a lack of standards for lipid-soluble arsenic compounds,which is one of the bottlenecks in the current analytical detection and toxicological studies of organic arsenic.In this study,four saturated arsenic-containing hydrocarbons,AsHC 318,AsHC 332,AsHC 346,and AsHC 374(The number is relative molecular mass),were successfully synthesized in three steps by using dimethylarsinic acid,potassium iodide,sodium hydroxide,and four brominated alkanes(1-Bromotetradecane,1-bromopentadecane,1-bromohexadecane,and 1-bromooctadecane)as raw materials.The structures of these four saturated arsenic-containing hydrocarbons were characterized by proton nuclear magnetic resonance(1H NMR)spectroscopy,13C nuclear magnetic resonance(13C NMR)spectroscopy,and high-resolution mass spectrometry(HR-MS).The yields of the method were 8%-10%,and the synthesized compounds could be used in subsequent toxicity evaluation experiments to assess the toxic effects and mechanisms of action of arsenic-containing hydrocarbons.This study provided an effective method for synthesis of arsenic-containing hydrocarbons,enriching the synthesis methods of arsenic-containing hydrocarbons,and provided raw materials for the subsequent toxicological studies of arsenic-containing hydrocarbons.

Decabromodiphenyl ether(BDE-209)and decabromodiphenyl ethane(DBDPE)are widely used brominated flame retardants,which have been detected in the atmosphere,water,soil,and various organisms.In this study,a method based on high-performance liquid chromatography-inductively coupled plasma-mass spectrometry(HPLC-ICP-MS)was developed for determination of BDE-209 and DBDPE in sediment.Firstly,the target compounds in the sediments were extracted by accelerated solvent extraction(ASE),and the extraction solvent was hexane/dichloromethane(1∶1,V/V).The extract was concentrated by rotary evaporation and purified by a composite silica gel column(6 g neutral silica gel,8 g acidic silica gel,and 4 g anhydrous sodium sulfate),concentrated by nitrogen blowing,and then re-dissolved with 1 mL of toluene for instrumental determination.The chromatographic separation was carried out on a TC-C18(2)column(250 mm×4.6 mm)with isocratic elution using methanol-isopropanol-water(89∶6∶5,V/V)as the mobile phase,and the samples were separated within 20 min.Further,the Br element was quantified by ICP-MS to realize the detection of the target.The results showed that the method established in this study exhibited good linearity(R2>0.999)in the range of 100-10000 ng/mL,and the limits of quantification(LOQs)of the method were 2.0 ng/g for BDE-209 and 10.0 ng/g for DBDPE,with the relative standard deviations(RSDs,n=3)lower than 10%,and the recoveries were in the acceptable range(80.9%-120.7%).The matrix effect was effectively controlled within 10%.In addition,by analyzing the actual sediment samples from Guangxi,a background point,and Taizhou,Zhejiang,a typical contaminated area,it was found that neither BDE-209 nor DBDPE was detected in the sediment from Guangxi,while the concentrations of BDE-209 and DBDPE in the sediment from Zhejiang ranged from 1591.8 to 3362.9 ng/g,which further demonstrated the applicability and reliability of the method for analyzing actual environmental samples.This study provided a strong technical support for the accurate detection of POPs in the environment.

Objective:To investigate the effects of metformin on esophageal squamous cell carcinoma cell growth, migration and angiogenesis by regulating the expression of ALKBH3.Methods:Human esophageal cancer TE-1 cells were treated with different concentrations (0, 0.5, 1.0, 2.0, 4.0, 8.0 mmol/L) of metformin, and they were divided into a blank control group, low- (0.5 mmol/L), medium- (1.0 mmol/L), and high- (2.0 mmol/L) concentration metformin groups, a metformin (2.0 mmol/L) +pcDNA-NC group, and a metformin (2.0 mmol/L) +pcDNA-ALKBH3 group. The cell viability was determined by the CCK-8 method. The cell proliferation ability was detected by the clone formation assay. The cell migration and invasion abilities were examined by the Transwell assay. The cell apoptosis was detected by flow cytometry. The tube formation ability of cells was detected by the angiogenesis assay. A xenograft tumor model was constructed using 4- to 6-week-old male BALB/c thymus-less nude mice, which were divided into a model control group, a metformin group, a metformin+pcDNA-NC group, and a metformin+pcDNA-ALKBH3 group using a random number table method, and with six in each group. And the volume and weight of the tumor were measured. The protein expression levels of apoptosis-related proteins Bcl-2, Bax, ALKBH3 and vascular endothelial growth factor A (VEGF-A) were detected by Western blotting. The expression of CD31 protein was detected by immunohistochemistry.Results:After treating TE-1 cells with 0, 0.5, 1.0, 2.0, 4.0, and 8.0 mmol/L metformin for 48 hours, the cell viability was (100.00±0.00) %, (90.31±5.23) %, (81.25±8.65) %, (63.52±6.80) %, (54.64±5.35) %, and (31.48±4.21) %, respectively, with a statistically significant difference ( F=98.11, P<0.001). There were statistically significant differences in cell viability between 0.5, 1.0, 2.0, 4.0, 8.0 mmol/L and 0 mmol/L (all P<0.05). The IC 50 of metformin for TE-1 cells was 4.46 mmol/L. The numbers of colony formations of TE-1 cells in the blank control group, low-, medium-, and high-concentration metformin groups, metformin+pcDNA-NC group, and metformin+pcDNA-ALKBH3 group were 153.15±13.55, 134.80±11.62, 116.24±10.43, 93.17±8.85, 89.39±8.46, 110.26±7.21, respectively, with a statistically significant difference ( F=34.28, P<0.001); the numbers of colony formations of TE-1 cells in the metformin groups at different concentrations decreased significantly with the increase in metformin concentration (both P<0.05); compared with the metformin+pcDNA-NC group, the number of colony formations of cells in the metformin+pcDNA-ALKBH3 group increased ( P<0.05). The numbers of migration of TE-1 cells of 6 groups were 152.13±13.40, 133.85±10.72, 115.28±8.64, 91.16±7.89, 85.39±7.23, 116.85±8.36, the numbers of invasion were 135.22±10.77, 112.07±9.53, 86.30±7.45, 69.53±6.74, 65.81±5.65, 79.80±6.32, respectively, with statistically significant differences ( F=41.35, P<0.001; F=69.06, P<0.001); the numbers of migrated and invaded cells in the metformin groups at different concentrations decreased significantly with the increase in metformin concentration (all P<0.05); compared with the metformin+pcDNA-NC group, the numbers of migrated and invaded cells in the metformin+pcDNA-ALKBH3 group increased significantly (both P<0.05). The apoptosis rates of TE-1 cells in 6 groups were (3.22±1.13) %, (13.82±1.90) %, (22.67±2.53) %, (29.18±3.24) %, (26.84±2.75) %, and (16.36±1.63) %, respectively, with a statistically significant difference ( F=103.66, P<0.001); the apoptosis rates of cells in the metformin groups at different concentrations gradually increased with the increase in metformin concentration (both P<0.05); compared with the metformin+pcDNA-NC group, the apoptosis rate of cells in the metformin+pcDNA-ALKBH3 group was relatively lower ( P<0.05). The tubular structure of cells in blank control group was intact, and there were different degrees of damage to the tubular structure of cells in the low-, medium-, high- concentration metformin groups, the degree of damage to the tubular structure of cells in the metformin+pcDNA-ALKBH3 group was reduced. The numbers of cellular tubular structures of TE-1 cells in the 6 groups were 38.35±3.20, 27.15±2.64, 15.92±3.14, 7.39±1.50, 8.61±1.37, and 29.33±4.20, respectively, with a statistically significant difference ( F=113.92, P<0.001); the number of cellular tubular structures in the low-, medium-, and high- concentration metformin groups gradually decreased (both P<0.05); the number of cellular tubular structures in the metformin+pcDNA-ALKBH3 group was more than that in the metformin+pcDNA-NC group ( P<0.05). There were statistically significant differences in the protein expressions of Bcl-2, Bax, ALKBH3, and VEGF-A in TE-1 cells among 6 groups ( F=56.36, P<0.001; F=57.26, P<0.001; F=159.30, P<0.001; F=132.89, P<0.001); compared with the blank control group, the protein expressions of Bcl-2, ALKBH3, and VEGF-A in the metformin groups at different concentrations decreased, while the protein expression of Bax increased (all P<0.05); compared with the metformin+pcDNA-NC group, the protein expressions of Bcl-2, ALKBH3, and VEGF-A in the metformin+pcDNA-ALKBH3 group increased, and the expression level of Bax decreased (all P<0.05). The weights of tumors in the model control group, metformin group, metformin+pcDNA-NC group, and metformin+pcDNA-ALKBH3 group were (1.16±0.12), (0.46±0.05), (0.50±0.06), (1.19±0.14) g, the volumes of tumors were (878.36±108.93), (413.59±50.23), (439.78±51.39), (793.75±96.98) mm 3, with statistically significant differences ( F=96.61, P<0.001; F=51.90, P<0.001); the weight of tumors were lower and the volume of tumors were smaller in the metformin group than those in the model control group (both P<0.05), the weight of tumors were higher and the volume of tumors were bigger in the metformin+pcDNA-ALKBH3 group than those in the metformin group and the metformin+pcDNA-NC group (all P<0.05). CD31 was mainly distributed in the cytoplasm and cell membrane of tumor cells. There were statistically significant differences in the positive rates of CD31 and the protein expression levels of VEGF-A in transplanted tumor tissues among 4 groups ( F=7.12, P=0.002; F=48.81, P<0.001); the positive rate of CD31 and the protein expression level of VEGF-A in the metformin group were lower than those in the model control group; the positive rate of CD31 and the protein expression level of VEGF-A in the metformin+pcDNA-ALKBH3 group were higher than those in the metformin group and the metformin+pcDNA-NC group (all P<0.05) . Conclusions:Metformin may inhibit the proliferation, migration, and tumor angiogenesis of esophageal squamous cell carcinoma by reducing ALKBH3 expression.

ObjectiveTo investigate the changing trend of hemoglobin （Hb） and related influencing factors in patients with liver failure after artificial liver support system （ALSS） therapy. MethodsA total of 106 patients with liver failure who were hospitalized and received ALSS therapy in our hospital from January to December 2018 were enrolled and analyzed in terms of clinical data and red blood cell parameters such as Hb， mean corpuscular volume （MCV）， mean corpuscular hemoglobin （MCH）， mean corpuscular hemoglobin concentration （MCHC）， and red blood cell distribution width-coefficient of variation （RDW-CV）. A one-way repeated-measures analysis of variance was used for comparison of continuous data with repeated measurement between groups， and the paired t-test was used for comparison between two groups. The Kruskal-Wallis H test was used for comparison of continuous data with skewed distribution between multiple groups， the Mann-Whitney U test was used for further comparison between two groups. Univariate and multivariate linear regression analyses were used to identify the influencing factors for the reduction in Hb after ALSS therapy. ResultsThe 106 patients with liver failure received 606 sessions of ALSS therapy， and Hb was measured for 402 sessions before and after treatment. There was a significant reduction in Hb after ALSS therapy in the patients with liver failure （97.49±20.51 g/L vs 109.38±20.22 g/L， t=32.764， P<0.001）. Longitudinal observation was further performed for 14 patients with liver failure， and the results showed that the level of Hb was 108.50±21.61 g/L before the last session of ALSS therapy， with certain recovery compared with the level of Hb （103.14±19.15 g/L） on the second day after ALSS， and there was an increase in Hb on day 3 （102.57±21.73 g/L） and day 7 （105.57±22.04 g/L） after surgery. The level of Hb in patients with liver failure on the second day after ALSS decreased with the increase in the number of ALSS sessions （F=8.996， P<0.001）， while MCV and MCH gradually increased with the increase in the number of ALSS sessions （F=9.154 and 13.460， P=0.004 and P<0.001）， and RDW-CV first gradually increased and then gradually decreased （F=4.520， P=0.032）； MCHC showed fluctuations with no clear trend （F=0.811， P=0.494）. The multivariate linear regression analysis showed that the duration of ALSS therapy， the mode of ALSS therapy， and initial treatment were independent risk factors for the reduction in Hb after ALSS therapy. ConclusionALSS therapy can influence the level of peripheral blood Hb in patients with liver failure， and patient blood management should be strengthened for patients with liver failure who are receiving ALSS therapy.

The traditional teaching model centered on courses has disadvantages such as interdisciplinary barriers, repetitive learning of content, and students being unable to enter clinical practice early. The Human Body Overview I is a core course at the basic stage under the integrated curriculum system centered on "organ-systems" at Chongqing Medical University. The course deeply integrates interdisciplinary resources and reconstructs the contents of systematic anatomy, embryology, and physiology under the traditional teaching model. The "Three in One" curriculum ideology and politics are implemented to assist students in their comprehensive development. By strengthening the cultivation of clinical application abilities and empowering with virtual simulation technology, the teaching effectiveness and quality have been improved. The teaching practice of the Human Body Overview I suggests that the teaching reform of integrated curriculum at the basic stage has broken interdisciplinary barriers, avoided repetitive learning of contents, and promoted the cultivation of students' interdisciplinary integration ability and clinical application ability. It can provide a reference for the teaching reform of integrated curriculum for other colleges.