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.

Background Pulmonary heart disease (PHD) is a critical cardiopulmonary disease in high-altitude areas, with pulmonary hypertension (PH) as its central pathological basis. Cold and hypoxia are vital environmental characteristics of high-altitude regions; however, their joint effect on the hospitalization risk for PHD and the underlying biological mechanisms remain unclear. Objective To evaluate the associations of cold, hypoxia, and their joint exposure with PHD hospitalization risk, and to investigate PH-related pathological changes induced by combined cold and hypoxic exposure and the intervention effects of γ-aminobutyric acid (GABA) in rats. Methods Based on hospitalization data for 92986 PHD cases from 333 hospitals in Gansu Province (2018–2022), a generalized additive model (GAM) with a quasi-Poisson distribution was used to assess the associations between daily mean temperature, atmospheric oxygen content (AOC) and the daily number of PHD hospitalizations. Four joint exposure categories were constructed using the fifth percentile of temperature (P₅, −7.90℃) and AOC grades (high or low) to assess the associations between different exposure combinations and daily PHD hospital admissions. To further investigate PH-related pathological changes and the intervention effects of GABA, 24 specific-pathogen-free male Sprague–Dawley rats were randomly assigned to four groups (n=6): normal temperature and normoxia control group (NC), combined cold and hypoxia exposure group (CH), combined exposure plus low-dose GABA intervention group (CHL), and combined exposure plus high-dose GABA intervention group (CHH). After 5 weeks, pulmonary hemodynamics and vascular remodeling were evaluated. Gut microbiota and inflammatory cytokines in lung tissue were assessed using 16S rRNA sequencing and enzyme-linked immunosorbent assay (ELISA), respectively. Results Each 1 g·m⁻³ decrease in AOC and each 1 ℃ decrease in daily mean temperature were associated with 2.6% (RR=1.026, 95%CI: 1.024, 1.027) and 1.8% (RR=1.018, 95%CI: 1.015, 1.020) increases in PHD hospitalization risk, respectively. Compared with the non-low-temperature and high-AOC group, the low-temperature and low-AOC group had the highest risk estimate (RR=1.673, 95%CI: 1.567, 1.785). Animal experiments demonstrated that, compared with the NC group, rats in the CH group showed shortened pulmonary artery acceleration time (PAT) and increased mean pulmonary artery pressure (MPAP), right ventricular hypertrophy index (RVHI), pulmonary arterial wall thickness, and α-smooth muscle actin (α-SMA) expression (P<0.05). The Observed Species and Chao1 indices of the gut microbiota were significantly lower in the CH group than in the NC group (P<0.05), while levels of tumor necrosis factor-alpha (TNF-α) and interleukin-1beta (IL-1β) in lung tissue were elevated (P<0.05). GABA intervention improved selected hemodynamic, vascular remodeling, and inflammatory indices. Conclusion Decreases in daily mean temperature and AOC are associated with an increased risk of PHD hospitalization, with the highest risk estimate observed in the low-temperature and low-AOC group. Animal experiments suggest that combined cold and hypoxic exposure induce PH-related pathological changes accompanied by alterations in the gut microbiota and pulmonary inflammation. GABA may partially ameliorate these changes.

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.

AIM:To investigate the preventive and therapeutic effects of sesamin(SES)on fatty liver disease in rats with hypertension combined with dyslipidemia,and to explore the potential mecha-nisms based on mRNA-seq.METHODS:Spontane-ously hypertensive rats(SHRs)were fed a high-fat,high-cholesterol diet to establish a rat model of hy-pertension combined with dyslipidemia,and then treated with SES for 16 weeks continuously.The ex-periment was divided into four groups:WKY,SHR,Model,and Model+SES(160 mg·kg-1·d-1).Blood pressure was measured using the tail-cuff method.Body weight was monitored,and body mass index was calculated.Liver morphology was detected by ultrasound,and liver thickness was measured.Liver wet weight was weighed,and liver index was calcu-lated.Liver volume was detected by the water dis-placement method.Serum triglycerides(TG),total cholesterol(TC),low-density lipoprotein cholesterol(LDL-C),high-density lipoprotein cholesterol(HDL-C),alanine aminotransferase(ALT),aspartate amino-transferase(AST),and total bile acids(TBA)were de-tected by ELISA.Liver sequencing analysis was per-formed using mRNA-seq.Liver histomorphological changes were observed by HE staining.The degree of hepatic steatosis was observed by Oil Red O stain-ing,and the degree of hepatic fibrosis was observed by MASSON staining.The mRNA expression of Al-dh1a7,Nnmt,Irs2,Pltp,and Scd was detected by q-PCR.The protein expression of Scd,Nnmt,AMPK,p-AMPK,PPARα,and PPARγ was detected by Western blotting.RESULTS:After 16 weeks of continuous SES administration to rats with hypertension combined with dyslipidemia,blood pressure was significantly reduced(P＜0.01),and body weight was decreased.Serum TG,TC,and LDL-C levels were decreased,while HDL-C levels were increased.Serum ALT and AST levels were decreased.Liver weight,organ in-dex,liver thickness,and liver volume were de-creased.The degree of hepatic steatosis and hepat-ic fibrosis was improved.A total of 545 differentially expressed mRNAs were identified in the livers of rats in each group,of which 278 were upregulated and 267 were downregulated.Among the 27 com-monly differentially expressed mRNAs,five mRNAs related to lipid metabolism were screened,namely Aldh1a7,Nnmt,Irs2,Pltp,and Scd.KEGG enrich-ment analysis showed that the enriched pathways were AMPK and PPAR.Further validation revealed that in the SES-treated group,the mRNA expression of Scd in the liver was decreased,while the mRNA expression of Nnmt was increased.The protein ex-pression of Scd was decreased,while the protein ex-pression of Nnmt,AMPK,p-AMPK,PPARα,and PPARγ was increased.CONCLUSION:SES has preven-tive and therapeutic effects on fatty liver disease in rats with hypertension combined with dyslipidemia,and its mechanism of action may be related to the reduction of Scd expression levels in the liver and the increase in the expression of Nnmt,AMPK,p-AMPK,PPARα,and PPARγ.

In this study,an ultraviolet(UV)/fluorescence dual-modal sensor was constructed by combining the catalytic properties of aldehyde dehydrogenase(ALDH)with the fluorescence inner filter effect of bovine serum albumin(BSA),realizing highly sensitive and highly selective detection of acetaldehyde in food.Acetaldehyde could react with oxidized coenzyme I(NAD+)to generate acetic acid and reduced coenzyme I(NADH)under catalytic condition by ALDH,and a quantitative relationship between acetaldehyde concentration and UV signal for UV detection based on the characteristic UV absorption peak of NADH at 340 nm was established.Meanwhile,an acetaldehyde detection channel based on fluorescence signal changes was built on the basis of the property that the fluorescence emission of BSA(as a fluorescent indicator)at 340 nm could be effectively quenched by the generated NADH,thus forming a″one-reaction dual-signal″detection mode.The experimental results showed that the acetaldehyde concentration in the range of 0.01?5.0 mg/L had a good linear relationship with both UV and fluorescence signals,and the limit of detection(LOD)was 0.003 mg/L for the UV mode and 0.005 mg/L for the fluorescence mode,and no significant fluctuations were observed when 50-fold concentrations of acetaldehyde analogs and common interfering substances were added.When the dual-modal sensor was applied to detection of acetaldehyde in food samples such as yogurt and wine,the relative error between its quantitative results and those of high-performance liquid chromatography(HPLC)was less than±4.0%.The dual-modal cross-validation strategy could improve the detection reliability through signal mutual verification,providing an innovative solution for the rapid detection of acetaldehyde contamination in food.

OBJECTIVE: We aimed to investigate the patterns of fasting blood glucose (FBG) trajectories and analyze the relationship between various occupational hazard factors and FBG trajectories in male steelworkers. METHODS: The study cohort included 3,728 workers who met the selection criteria for the Tanggang Occupational Cohort (TGOC) between 2017 and 2022. A group-based trajectory model was used to identify the FBG trajectories. Environmental risk scores (ERS) were constructed using regression coefficients from the occupational hazard model as weights. Univariate and multivariate logistic regression analyses were performed to explore the effects of occupational hazard factors using the ERS on FBG trajectories. RESULTS: FBG trajectories were categorized into three groups. An association was observed between high temperature, noise exposure, and FBG trajectory ( P < 0.05). Using the first quartile group of ERS1 as a reference, the fourth quartile group of ERS1 had an increased risk of medium and high FBG by 1.90 and 2.21 times, respectively (odds ratio [ OR] = 1.90, 95% confidence interval [ CI]: 1.17-3.10; OR = 2.21, 95% CI: 1.09-4.45). CONCLUSION An association was observed between occupational hazards based on ERS and FBG trajectories. The risk of FBG trajectory levels increase with an increase in ERS.
Humans ; Male ; Adult ; Blood Glucose/analysis* ; China ; Prospective Studies ; Occupational Exposure/adverse effects* ; Risk Factors ; Middle Aged ; Steel ; Fasting/blood* ; Metal Workers ; East Asian People

OBJECTIVE: To investigate chronic hepatitis C virus (HCV) infection's effect on gestational liver function, pregnancy and delivery complications, and neonatal development. METHODS: A total of 157 HCV antibody-positive (anti-HCV[+]) and HCV RNA(+) patients (Group C) and 121 anti-HCV(+) and HCV RNA(-) patients (Group B) were included as study participants, while 142 anti-HCV(-) and HCV RNA(-) patients (Group A) were the control group. Data on biochemical indices during pregnancy, pregnancy complications, delivery-related information, and neonatal complications were also collected. RESULTS: Elevated alanine aminotransferase (ALT) rates in Group C during early, middle, and late pregnancy were 59.87%, 43.95%, and 42.04%, respectively-significantly higher than Groups B (26.45%, 15.70%, 10.74%) and A (23.94%, 19.01%, 6.34%) ( P < 0.05). Median ALT levels in Group C were significantly higher than in Groups A and B at all pregnancy stages ( P < 0.05). No significant differences were found in neonatal malformation rates across groups ( P > 0.05). However, neonatal jaundice incidence was significantly greater in Group C (75.16%) compared to Groups A (42.25%) and B (57.02%) ( χ ² = 33.552, P < 0.001). HCV RNA positivity during pregnancy was an independent risk factor for neonatal jaundice ( OR = 2.111, 95% CI 1.242-3.588, P = 0.006). CONCLUSIONS Chronic HCV infection can affect the liver function of pregnant women, but does not increase the pregnancy or delivery complication risks. HCV RNA(+) is an independent risk factor for neonatal jaundice.
Humans ; Female ; Pregnancy ; Adult ; Pregnancy Complications, Infectious/epidemiology* ; Retrospective Studies ; Pregnancy Outcome ; Infant, Newborn ; Viremia/virology* ; Hepatitis C ; Hepacivirus/physiology* ; Hepatitis C, Chronic/virology* ; Young Adult ; Alanine Transaminase/blood*

PURPOSE: To investigate the protective effect of sub-hypothermic mechanical perfusion combined with membrane lung oxygenation on ischemic hypoxic injury of yorkshire brain tissue caused by traumatic blood loss. METHODS: This article performed a random controlled trial. Brain tissue of 7 yorkshire was selected and divided into the sub-low temperature anterograde machine perfusion group (n = 4) and the blank control group (n = 3) using the random number table method. A yorkshire model of brain tissue injury induced by traumatic blood loss was established. Firstly, the perfusion temperature and blood oxygen saturation were monitored in real-time during the perfusion process. The number of red blood cells, hemoglobin content, NA⁺, K⁺, and Ca²⁺ ions concentrations and pH of the perfusate were detected. Following perfusion, we specifically examined the parietal lobe to assess its water content. The prefrontal cortex and hippocampus were then dissected for histological evaluation, allowing us to investigate potential regional differences in tissue injury. The blank control group was sampled directly before perfusion. All statistical analyses and graphs were performed using GraphPad Prism 8.0 Student t-test. All tests were two-sided, and p value of less than 0.05 was considered to indicate statistical significance. RESULTS: The contents of red blood cells and hemoglobin during perfusion were maintained at normal levels but more red blood cells were destroyed 3 h after the perfusion. The blood oxygen saturation of the perfusion group was maintained at 95% - 98%. NA⁺ and K⁺ concentrations were normal most of the time during perfusion but increased significantly at about 4 h. The Ca²⁺ concentration remained within the normal range at each period. Glucose levels were slightly higher than the baseline level. The pH of the perfusion solution was slightly lower at the beginning of perfusion, and then gradually increased to the normal level. The water content of brain tissue in the sub-low and docile perfusion group was 78.95% ± 0.39%, which was significantly higher than that in the control group (75.27% ± 0.55%, t = 10.49, p < 0.001), and the difference was statistically significant. Compared with the blank control group, the structure and morphology of pyramidal neurons in the prefrontal cortex and CA1 region of the hippocampal gyrus were similar, and their integrity was better. The structural integrity of granulosa neurons was destroyed and cell edema increased in the perfusion group compared with the blank control group. Immunofluorescence staining for glail fibrillary acidic protein and Iba1, markers of glial cells, revealed well-preserved cell structures in the perfusion group. While there were indications of abnormal cellular activity, the analysis showed no significant difference in axon thickness or integrity compared to the 1-h blank control group. CONCLUSIONS Mild hypothermic machine perfusion can improve ischemia and hypoxia injury of yorkshire brain tissue caused by traumatic blood loss and delay the necrosis and apoptosis of yorkshire brain tissue by continuous oxygen supply, maintaining ion homeostasis and reducing tissue metabolism level.
Animals ; Perfusion/methods* ; Disease Models, Animal ; Brain Injuries/etiology* ; Swine ; Male ; Hypothermia, Induced/methods*

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.