Chronic pain is a complex condition shaped by long-standing alterations in both physiological and psychological processes. Rather than representing a simple continuation of acute nociceptive signaling, chronic pain is increasingly understood as the outcome of progressive dysregulation within distributed neural systems that govern sensation, affect, motivation, and cognitive control. Neuroimaging and electrophysiological studies indicate that this state is accompanied by extensive plastic changes in deep brain structures and large-scale networks. Beyond well-described central sensitization processes, chronic pain is characterized by disrupted oscillatory rhythms and altered connectivity within large-scale brain networks, including thalamo-cortical circuits and prefrontal-limbic-reward networks. These findings support a conceptual shift from viewing chronic pain as a focal, lesion-driven phenomenon toward recognizing it as a disorder of distributed network pathology. Pharmacological treatments remain central to clinical practice, yet their long-term efficacy is often limited and frequently accompanied by substantial side effects. The ongoing concerns about opioid-related risks and the inadequate therapeutic response in a subset of patients highlight the need for safe, non-pharmacological approaches that can address not only pain but also comorbid disturbances in mood, sleep, and social functioning. Neuromodulation provides a promising path toward mechanism-based and non-pharmacological management of chronic pain by employing physical or chemical stimulation to alter the excitability and synchrony of specific neural populations within central, peripheral, and autonomic systems. While invasive deep brain stimulation demonstrates that targeting deep brain structures can be effective, its clinical application is restricted by surgical risks and cost, highlighting the importance of non-invasive techniques capable of reaching deep targets. Current non-invasive approaches, such as transcranial electric stimulation, are constrained by limited penetration depth and insufficient spatial precision. These limitations hinder reliable engagement of deep regions implicated in pain, including the thalamus and nucleus accumbens, and tend to produce broad, non-specific modulation of cross-network oscillatory activity. Temporal interference (TI) stimulation has emerged as a means of overcoming these obstacles. By delivering interacting high-frequency currents that generate a low-frequency envelope within the head, TI enables focal stimulation of deep targets while minimizing superficial current delivery. Recent multiscale modeling and animal studies indicate that TI exploits the nonlinear rectification properties of neuronal membranes in response to high-frequency carriers, as well as their phase-locked responses to low-frequency envelopes, to generate “peak-focused” electric fields in deep regions under relatively low superficial current loads. Moreover, TI appears to exhibit potential advantages in terms of cell-type selectivity and rhythm-specific engagement, including differential responses across neuronal subtypes and distinct coupling to θ-, β-, and γ-band oscillations. These features suggest a promising avenue for correcting abnormal rhythms and network dynamics that contribute to chronic pain. This review summarizes current knowledge of the neural mechanisms underlying chronic pain and recent advances in TI research. It examines functional disturbances across key pain-related regions and networks, outlines the principles and technical characteristics of TI, and discusses potential deep-brain targets and stimulation strategies relevant to chronic pain. Evidence to date indicates that TI, with its non-invasiveness, tolerability, and capacity for precise deep brain modulation, holds great promise for the management of treatment-resistant chronic pain and may evolve into a new generation of precise and efficient non-pharmacological analgesic strategies.

Chronic pain is a complex condition shaped by long-standing alterations in both physiological and psychological processes. Rather than representing a simple continuation of acute nociceptive signaling, chronic pain is increasingly understood as the outcome of progressive dysregulation within distributed neural systems that govern sensation, affect, motivation, and cognitive control. Neuroimaging and electrophysiological studies indicate that this state is accompanied by extensive plastic changes in deep brain structures and large-scale networks. Beyond well-described central sensitization processes, chronic pain is characterized by disrupted oscillatory rhythms and altered connectivity within large-scale brain networks, including thalamo-cortical circuits and prefrontal-limbic-reward networks. These findings support a conceptual shift from viewing chronic pain as a focal, lesion-driven phenomenon toward recognizing it as a disorder of distributed network pathology. Pharmacological treatments remain central to clinical practice, yet their long-term efficacy is often limited and frequently accompanied by substantial side effects. The ongoing concerns about opioid-related risks and the inadequate therapeutic response in a subset of patients highlight the need for safe, non-pharmacological approaches that can address not only pain but also comorbid disturbances in mood, sleep, and social functioning. Neuromodulation provides a promising path toward mechanism-based and non-pharmacological management of chronic pain by employing physical or chemical stimulation to alter the excitability and synchrony of specific neural populations within central, peripheral, and autonomic systems. While invasive deep brain stimulation demonstrates that targeting deep brain structures can be effective, its clinical application is restricted by surgical risks and cost, highlighting the importance of non-invasive techniques capable of reaching deep targets. Current non-invasive approaches, such as transcranial electric stimulation, are constrained by limited penetration depth and insufficient spatial precision. These limitations hinder reliable engagement of deep regions implicated in pain, including the thalamus and nucleus accumbens, and tend to produce broad, non-specific modulation of cross-network oscillatory activity. Temporal interference (TI) stimulation has emerged as a means of overcoming these obstacles. By delivering interacting high-frequency currents that generate a low-frequency envelope within the head, TI enables focal stimulation of deep targets while minimizing superficial current delivery. Recent multiscale modeling and animal studies indicate that TI exploits the nonlinear rectification properties of neuronal membranes in response to high-frequency carriers, as well as their phase-locked responses to low-frequency envelopes, to generate “peak-focused” electric fields in deep regions under relatively low superficial current loads. Moreover, TI appears to exhibit potential advantages in terms of cell-type selectivity and rhythm-specific engagement, including differential responses across neuronal subtypes and distinct coupling to θ-, β-, and γ-band oscillations. These features suggest a promising avenue for correcting abnormal rhythms and network dynamics that contribute to chronic pain. This review summarizes current knowledge of the neural mechanisms underlying chronic pain and recent advances in TI research. It examines functional disturbances across key pain-related regions and networks, outlines the principles and technical characteristics of TI, and discusses potential deep-brain targets and stimulation strategies relevant to chronic pain. Evidence to date indicates that TI, with its non-invasiveness, tolerability, and capacity for precise deep brain modulation, holds great promise for the management of treatment-resistant chronic pain and may evolve into a new generation of precise and efficient non-pharmacological analgesic strategies.

This study was aimed at identifying the pathogenic bacteria responsible for the death of a young tiger at the Fujian Meihua Mountain South China Tiger Breeding Research Institute.Tissue samples from the lungs,liver,and intestines of the deceased tiger were collected,and the bacteria were cultured inasterile environment.The bacterial strains were characterized according to their morphological and molecular biological properties,including assessment of virulence genes and antibiotic resistance genes,mouse lethality tests,and antibiotic susceptibility evaluations.A predominant bacterial strain isolated from the liver of the deceased tiger was identified as enterotoxigenic Escherichia coli(ETEC)strain Tiger22513F.Phylogenetic analysis of the 16S rRNA gene revealed that the Tiger22513F strain exhibited close genetic similarity to the reference strain ETEC(MF919609.1),with 99.9%nucleotide similarity,and resided on the same evolutionary branch.The Tiger22513F strain contained 11 antibiotic resistance genes(tetA,sul1,sul3,cmlA,floR,blaTEM,blaSHV,blaCMY-2,qnrA,qnrS,and qnrD)along with five virulence genes(VT1,fyuA,tsh,iucD,and ST).Mouse lethality tests indicated significant pathogenicity toward mice,affecting primarily the lungs,liver,and intestines.Antibiotic susceptibility testing demonstrated that this strain exhibited resistance to various classes of beta-lactam antibiotics,as well as quinolones and aminoglycosides.This investigation successfully isolated a multi-drug resistant enterotoxigenic Escherichia coli strain with pronounced pathogenicity from the liver of a deceased tiger;thus providing valuable scientific insights for clinical diagnosis,as well as prevention and control measures,against ETEC infections in South China tigers.

AIM To investigate the effects of Changpu Yujin Decoction(CPYJD)on striatal mitophagy and PINK1/Parkin signaling pathway in a rat model of Tourette syndrome(TS).METHODS Thirty-six SPF male SD rats were randomly assigned to the control group(n=9)and the TS modeling group(n=27).Rats in the modeling group received daily intraperitoneal injections of 3,3'-iminodipropionitrile(IDPN)(300 mg/kg)for 7 consecutive days to establish the TS model.Post-modeling,successfully induced TS rats were re-randomized into model group(no treatment),tiapride group(47.91 mg/kg)and CPYJD group(77.28 g/kg).All groups received their respective interventions via intragastric administration daily for 28 days.Following drug administration,behavioral scores were assessed in each group.Pathological alterations in the striatum were examined using HE staining,while ultrastructural changes were evaluated by transmission electron microscopy(TEM).Neuronal apoptosis was quantified via TUNEL staining,and ROS levels in striatum were measured by ELISA.Co-localization of PINK1 and LC3B was assessed using immunofluorescence(IF).Finally,mRNA and protein expressions of PINK1,Parkin,Beclin-1,P62 and LC3B(LC3B-Ⅱ/Ⅰ ratio)were analyzed by RT-qPCR and Western blot.RESULTS Compared to the control group,the model group demonstrated significantly increased behavioral scores(P＜0.01),elevated neuronal apoptosis rate and higher ROS levels in the striatum(P＜0.01);severe neuronal and mitochondrial damage in the striatum;significantly reduced mRNA and protein expressions of PINK1,Parkin,Beclin-1 and LC3B(LC3B-Ⅱ/Ⅰ ratio)in the striatum(P＜0.01);markedly upregulated P62 mRNA and protein expressions(P＜0.01).Compared to the model group,both the tiapride and CPYJD intervention groups exhibited significantly reduced behavioral scores(P＜0.01);decreased neuronal apoptosis rate and lower ROS levels(P＜0.01);improved pathological alterations in the striatal neurons and mitochondria;increased mRNA and protein expressions of PINK1,Parkin and Beclin-1 in the striatum(P＜0.05,P＜0.01);and decreased P62 mRNA and protein expressions(P＜0.01).Furthermore,the rats in the CPYJD group specifically showed elevated LC3B mRNA level and LC3B-Ⅱ/Ⅰ protein ratio in striatum(P＜0.05,P＜0.01).CONCLUSION The effect of CPYJD intervention in TS rats may involve activation of mitophagy through regulation of the PINK1/Parkin signaling pathway,improving mitochondrial function,reducing ROS levels,and thereby protecting neurons.

Objective:To explore the effect of remote motor imagery therapy on rehabilitation of patients with severe coronary heart disease(CHD)after percutaneous coronary intervention(PCI).Methods:This randomized con-trolled study enrolled 164 patients with severe CHD undergoing PCI who admitted in the First Affiliated Hospital of Hebei North University between January 2022 and January 2024.Patients were divided into control group(n=82)and intervention group(n=82).Patients in the control group was given conventional home nursing intervention comparing to those in the intervention group receiving additional remote motor imagery therapy.Both groups were intervened for 8 weeks.Indexes of pain,psychological emotion,ability of daily living,motor function and fall were compared between two groups.Results:Compared to those in control group after intervention,patients in interven-tion group had significant lower scores of visual analogue scale(VAS)[(2.03±0.81)points vs.(5.14±0.84)points],the Hospital anxiety and depression scale(HADS)anxiety subscale(HADS-A)[(4.89±0.84)points vs.(9.05±0.78)points],HADS depression subscale(H ADS-D)[(5.31±1.10)points vs.(10.13±0.82)points],HADS total score[(10.20±1.39)points vs.(19.18±1.18)points](P＜0.001 all),and significant higher 6-min walking distance(6MWD)[(439.31±16.51)m vs.(364.94±12.76)m],peak oxygen uptake(VO2 peak)[(20.28±2.40)ml·kg-1·min-1 vs.(17.26±1.35)ml·kg-1·min-1],anaerobic threshold oxygen consumption(VO2AT)[(17.04±1.18)ml·kg-1·min-1 vs.(13.62±1.16)ml·kg-1·min-1],scores of Chinese modified Fall Efficacy Scale(MFES)[(107.28±4.84)points vs.(87.41±4.73)points],ability of daily living(ADL)scale[(78.95±3.92)points vs.(68.00±4.10)points]and Barthel index[(85.83±2.50)points vs.(69.79±3.42)points](P＜0.001 all).We detected significant lower incidence of falling(7.50％vs.21.25％)in the intervention group compared to control group(P=0.013).Conclusion:Remote motor imagery therapy may strengthen motor function and ability of daily living,and relieve pain and negative emotions in patients with severe CHD after PCI.

Objective:To observe the early efficacy of intense pulsed light(IPL)combined with non-ablative fractional laser(NAFL)in preventing postoperative pathological scar formation and intervention of inflammatory factors.Methods:93 patients with postoperative pathological scar formation who were admitted to our hospital from March 2022 to September 2024 were selected,they were divided into control group A(silicone gel treatment,n=31),control group B(NAFL on the basis of control group A,n=31)and study group(IPL on the basis of control group B,n=31)using the random number table method.The clinical efficacy,simple quality of life scale(SF-36),vancouver scar scale(VSS),inflammatory factors[interleukin-6(IL-6),tumor necrosis factor-α(TNF-α),C-reactive protein(CRP)],and adverse reactions among three groups were compared.Results:The clinical total effective rate in the study group were higher than those in the control group A and control group B(P＜0.05).SF-36 increased sequentially and VSS decreased sequentially in control group A,control group B,and study group after treatment(P＜0.05).CRP,IL-6,and TNF-α decreased sequentially in control group A,control group B,and study group after treatment(P＜0.05).There was no significant difference in the incidence of adverse reactions among the three groups(P＞0.05).Conclusion:IPL combined with NAFL in preventing postoperative pathological scar formation,can effectively reduce scar formation,reduce inflammatory factors levels,improve patients' quality of life,and be safe and reliable.

Objective:To design two kinds of intensity modulated radiotherapy (IMRT) plans with different radiation field distributions,and to compare the dose differences of that at the dose of target region and organs at risk (OAR) for middle and lower esophageal cancer,so as to provide a reference for the design of IMRT plan. Methods:The data of 17 patients with middle and lower esophageal cancer who received IMRT at Shangluo Central Hospital from November 2022 to May 2023 were retrospectively analyzed. IMRT plans with different radiation fields for Plan 1 and Plan 2 were designed for each patient. The angles of radiation field for Plan 1 were 0°,80°,120°,160° and 200°,and those for Plan 2 were 30°,130°,180°,230° and 330°,respectively. The prescribed dose to the planning target volume (PTV) was 60 Gy/30 F. The differences in dosimetric parameters between the two plans were compared. Results:There were no statistically significant differences in the dose parameters of 2％,98％,50％ target dose (D2％,D98％,D50％),homogeneity index (HI),conformity index (CI) and monitor unit between the two groups (P>0.05). There were no significant differences in V5 of dual lungs,the mean dose (Dmean) of heart,and the maximum dose (Dmax) of spinal-cord between two groups (P>0.05). The volume percentage (V10,V20,V30) of dual lungs received radiation doses of 10,20 and 30 Gy,and the mean dose (Vmean) of lung in the Plan1 group reduced respectively 7.44％,21.16％,10.09％ and 5.31％ than those in the Plan2 group,and the differences of them were statistically significant (t=-5.845,-7.729,-2.247,-3.960,P<0.05). Heart V10 and V20 in the Plan1 group decreased respectively by 7.23％ and 5.78％,with statistical significance (t=-4.376,-3.523,P<0.01),while V30 and V40 of Plan 1 increased respectively by 2.7％ and 4.92％,without statistical significance (P>0.05). There was no significant difference in heart Dmean between the Plan1 group and the Plan2 group (P>0.05). Conclusion:Both two methods of distribution field can meet the clinical requirements,and Plan1 has more advantages in protecting organs at risk under the premise of meeting the requirements of target region.

Aim To investigate the high expression of LINC00626 in colorectal cancer,and explore the effects of LINC00626 on the proliferation,apoptosis,and drug sensitivity of colorectal cancer SW480 cells,as well as its underlying mechanisms.Methods Flu-orescence in situ hybridization(FISH)was used to de-tect the expression levels of LINC00626 in 38 colorec-tal cancer tissues and their corresponding adjacent nor-mal tissues.The JASPAR database was utilized to pre-dict co-expressed genes and their possible binding sites.Cell transfection technology was employed to knockdown LINC00626.Western blot and qRT-PCR techniques were used to verify the transfection efficien-cy.CCK-8 assay,cell apoptosis and necrosis staining,and Western blot were used to detect the changes in the proliferation,apoptosis,drug sensitivity,and ap-optotic proteins of SW480 cells,respectively.Results The FISH results indicated that LINC00626 was highly expressed in colorectal cancer tissues(P＜0.05).The expression of LINC00626 was not associat-ed with the age or gender of patients,but was related to the TNM stage and the presence of lymph node me-tastasis($ P＜0.05 $).The results of CCK-8 assay and cell apoptosis and necrosis staining showed that af-ter knockdown of LINC00626,the proliferation ability of SW480 cells decreased,the apoptosis level in-creased,and the drug resistance decreased(P＜0.05).Western blot results showed that with the de-crease in the expression level of LINC00626,the ex-pression of caspase-3 protein decreased,the expression of cleaved caspase-3 protein increased,and the expres-sion of Bcl-2 protein decreased(P＜0.05).Conclu-sions LINC00626 is highly expressed in colorectal cancer and is associated with the TNM stage and the presence of lymph node metastasis.LINC00626 can af-fect the proliferation,apoptosis,and drug sensitivity of SW480 cells and alter the expression of apoptotic pro-teins.

Aim To investigate the expression levels of cytoplasmic FMR1-interacting protein-1(CYFIP1)in colorectal cancer and assess the impact of CYFIP1 interaction on the proliferation and apoptosis of colorec-tal cancer cell HT29,along with its potential mecha-nisms.Methods Immunohistochemistry was em-ployed to assess CYFIP1 expression in 32 colorectal cancer tissues and adjacent tissues.Coexpressed genes were identified using the GEPIA2 website to predict potential correlations and binding sites.Following the construction of a siRNA-CYFIP1,alterations in cell proliferation,apoptosis,and levels of apoptosis-related proteins were evaluated through CCK-8 assay,Hoechst 33342/PI double staining assay,and Western blot a-nalysis,respectively.Results The immunohisto-chemical findings revealed a significantly elevated level of CYFIP1 expression in colorectal cancer tissues com-pared to paracancer tissues(P＜0.05).The expres-sion of CYFIP1 did not show any correlation with age and gender,but exhibited associations with TNM stage and lymph node metastasis(P＜0.05).A conserved TP53 binding site was predicted in the 3kbps DNA re-gion upstream of the CYFIP1 gene using GEPIA2,JASPAR databases,and rVista 2.0 promoter prediction software.Following transfection of HT29 cells with siRNA-CYFIP1,the clonogenesis and proliferation of cells significantly decreased(P＜0.05).Additional-ly,the levels of cleaved caspase-3 were elevated,while the expression levels of caspase-3 and Bcl-2 were reduced after transfection with siRNA-CYFIP1(P＜0.05),which might be related to the interaction be-tween CYFIP1 and TP53.Conclusions The upregu-lation of CYFIP1 in colorectal cancer is associated with TNM stage and lymph node metastasis.Upon silen-cing,CYFIP1 demonstrates the ability to suppress pro-liferation in HT29 cells and modulate the expression of apoptotic proteins.

Objective:To understand the contract renewal willingness and its influencing factors among rural order-oriented medical students in Shaanxi Province. M ethods This study employed an explanatory sequential mixed methods design to examine contract renewal patterns among rural order-oriented medical graduates. From February to July 2024, a questionnaire survey was conducted among rural order-oriented medical students who graduated from 2015 to 2023 in Shaanxi Province. The participants were first stratified into three strata based on their year of graduation and stage of service, and one-third of each stratum was randomly selected as the research subjects. Univariate and multivariate analysis methods were used to explore the influencing factors of their willingness to renew their service in rural areas. Secondly, qualitative research methods were employed to conduct thematic interviews with 36 targeted medical students on the influencing factors of their willingness to renew their service. Results:A total of 513 valid questionnaires were collected during the quantitative research phase, including 224 males and 289 females. Of these, 14 were from the 2015-2017 cohort, 247 from the 2018-2020 cohort, and 252 from the 2021-2023 cohort. The results showed that only 30.4%(156/513) of the orientation medical students were willing to practice in primary care after the period of service. Univariate analysis showed that there were six factors related to the willingness to renew the contract, the consistency of the source and implementation of the contract, the completion of the standardized training of residents, the satisfaction with primary work, professional identity, the ability of primary diagnosis and treatment, and the training system and the suitability of primary work. Multivariate analysis showed that the willingness to renew the contract was significantly higher in the students who had the same place of origin and the place of performance( OR=1.7, 95% CI: 1.1-2.6, P=0.022). The willingness to renew the contract was significantly higher among students who participated in the standardized residency training than those who completed the training( OR=2.0, 95% CI: 1.3-3.0, P=0.003), and students with a better fit between the training system and working in primary care were more likely to renew their contract( OR=4.1, 95% CI: 2.8-6.0, P<0.001). Four themes were extracted from the interview: subjective factors, objective environment, policy factors and other factors. Conclusions:The study shows that improving the consistency of the source of students and the implementation of the contract, strengthening the standardized training of residents, and optimizing the adaptation of the training system to the primary work are the key measures to improve the willingness of directional medical students to renew their contract at the primary level.