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: Based on the China-VHD database, this study sought to develop and validate a Valvular Heart Disease- specific Age-adjusted Comorbidity Index (VHD-ACI) for predicting mortality risk in patients with VHD. METHODS & RESULTS: The China-VHD study was a nationwide, multi-centre multi-centre cohort study enrolling 13,917 patients with moderate or severe VHD across 46 medical centres in China between April-June 2018. After excluding cases with missing key variables, 11,459 patients were retained for final analysis. The primary endpoint was 2-year all-cause mortality, with 941 deaths (10.0%) observed during follow-up. The VHD-ACI was derived after identifying 13 independent mortality predictors: cardiomyopathy, myocardial infarction, chronic obstructive pulmonary disease, pulmonary artery hypertension, low body weight, anaemia, hypoalbuminaemia, renal insufficiency, moderate/severe hepatic dysfunction, heart failure, cancer, NYHA functional class and age. The index exhibited good discrimination (AUC, 0.79) and calibration (Brier score, 0.062) in the total cohort, outperforming both EuroSCORE II and ACCI (P < 0.001 for comparison). Internal validation through 100 bootstrap iterations yielded a C statistic of 0.694 (95% CI: 0.665-0.723) for 2-year mortality prediction. VHD-ACI scores, as a continuous variable (VHD-ACI score: adjusted HR (95% CI): 1.263 (1.245-1.282), P < 0.001) or categorized using thresholds determined by the Yoden index (VHD-ACI ≥ 9 vs. < 9, adjusted HR (95% CI): 6.216 (5.378-7.184), P < 0.001), were independently associated with mortality. The prognostic performance remained consistent across all VHD subtypes (aortic stenosis, aortic regurgitation, mitral stenosis, mitral regurgitation, tricuspid valve disease, mixed aortic/mitral valve disease and multiple VHD), and clinical subgroups stratified by therapeutic strategy, LVEF status (preserved vs. reduced), disease severity and etiology. CONCLUSION The VHD-ACI is a simple 13-comorbidity algorithm for the prediction of mortality in VHD patients and providing a simple and rapid tool for risk stratification.

Nature killer(NK)cells are lymphocytes of the innate immune that play a significant role in aging through direct cell killing and secretion of cytokines.NK cells can delay the occurrence of age-related diseases and prolong lifespan by eliminating senescencent cells.Significant progress has been achieved in the research utilizing NK cells to improve aging.This review aims to summarize that the recent research on the mechanism of NK cells in the context of senescence, as well as the progress made in anti-senescence interventions through animal and clinical studies.Nevertheless, substantial challenges remain for the clinical application of NK cell-based anti-senescence therapies.

Aim To investigate the effect of tetrameth-ylpyrazine(TMP)on neuroinflammation after cerebral ischemia and hypoxia via mannose-binding lectin(MBL).Methods Patients diagnosed with ischaemic stroke at Shanxi Provincial People's Hospital were in-cluded in the study,and their clinicopathological data,as well as blood and urine samples,were collected with the consent of the patients and their families.Using these biological samples,differential proteins and tar-gets were identified by proteomic analysis and subse-quently verified with animal experiments.The mice were divided into the sham,dMCAO,and TMP(10,20,40 mg·kg-1)treatment groups.After seven days of drug administration,the modified neurological sever-ity score(mNSS)was used to assess the neurological function.TTC staining was used to detect the volume of cerebral infarction.Motor function was evaluated be-haviourally,and ELISA was used to detect MASP1,sC5b-9,TNF-α,IL-6,and IL-1β.Western blot was used to determine the expression of relevant proteins,such as MBL2,MASP2,and C3.Results Compared with the sham group,the dMCAO group exhibited in-creased neurological impairment,which was signifi-cantly ameliorated by TMP treatment.The expression levels of MBL2,C3 and MASP2 were elevated in the dMCAO group and were reduced following TMP treat-ment.Additionally,the dMCAO group showed elevat-ed expression of inflammatory factors IL-1 β,IL-6 and TNF-α,which were then suppressed by TMP treat-ment.Conclusion TMP inhibits the inflammatory re-sponse after ischemia and hypoxia by regulating MBL,thus attenuating brain injury.

Objective:To develop rat models of oral mucosa ulcer using distinct experimental methodologies,fulfilling research requirements and adhering to the ethical standards for animal care.Methods:96 SD rats were randomly allocated into groups.The rats in control group(n=8)were regularly fed without other treatment.Those in chemical cauterization groups were treated by 20％,40％,60％of glacial acetic acid(GAA)on oral mucosa(n=8);in mechanical damage groups by 30 000 r/min high speed drill induced trauma of 10,20 and 30 mm2 respectively(n=8);in ionizing radiation groups were treated with 10,12,15,20 and 30 Gy on the mucosa respectively(n=8).After the ulcer was appeared,the morphology of the mucosa were observed,the mucosal tissue lesions were examined by HE,Masson and immunofluorescence staining,the expression of TNF-α and IL-1β were detected by qPCR and ELISA respectively,and the body conditions such as diet and body weight of the rats were observed,the pain,dis-tress and discomfor of the rats were evaluated by MORTON&Griffits Guidelines.Results:40％and 60％GAA,20 mm2 and 30 mm2 friction damage and ionizing radiation of 12 Gy or greater may induce oral mucosa ulcer with a diseas coruse of 6-7 d in SD rats.TNF-α and IL-1β mRNA expression in the damaged tissue,the related protein expression in blood serum of the rats were in-creased.MORTON&Griffits Guidelines analysis showed 40％GAA,20 mm2 friction damage and 12 Gy ionizing radiation induced the lowest scores of pain,distress and discomfort of the rats with compatible oral mocosa ulcere induced by the relevat treatment.Conclusion:40％GAA,20 mm2 of friction damage and 12 Gy of ionizing radiation can reliably establish oral mucosa ulcer models and minimize adverse effects on SD rats,and accord with ethical standards of 3R for laboratory animal.

Objective:To develop rat models of oral mucosa ulcer using distinct experimental methodologies,fulfilling research requirements and adhering to the ethical standards for animal care.Methods:96 SD rats were randomly allocated into groups.The rats in control group(n=8)were regularly fed without other treatment.Those in chemical cauterization groups were treated by 20％,40％,60％of glacial acetic acid(GAA)on oral mucosa(n=8);in mechanical damage groups by 30 000 r/min high speed drill induced trauma of 10,20 and 30 mm2 respectively(n=8);in ionizing radiation groups were treated with 10,12,15,20 and 30 Gy on the mucosa respectively(n=8).After the ulcer was appeared,the morphology of the mucosa were observed,the mucosal tissue lesions were examined by HE,Masson and immunofluorescence staining,the expression of TNF-α and IL-1β were detected by qPCR and ELISA respectively,and the body conditions such as diet and body weight of the rats were observed,the pain,dis-tress and discomfor of the rats were evaluated by MORTON&Griffits Guidelines.Results:40％and 60％GAA,20 mm2 and 30 mm2 friction damage and ionizing radiation of 12 Gy or greater may induce oral mucosa ulcer with a diseas coruse of 6-7 d in SD rats.TNF-α and IL-1β mRNA expression in the damaged tissue,the related protein expression in blood serum of the rats were in-creased.MORTON&Griffits Guidelines analysis showed 40％GAA,20 mm2 friction damage and 12 Gy ionizing radiation induced the lowest scores of pain,distress and discomfort of the rats with compatible oral mocosa ulcere induced by the relevat treatment.Conclusion:40％GAA,20 mm2 of friction damage and 12 Gy of ionizing radiation can reliably establish oral mucosa ulcer models and minimize adverse effects on SD rats,and accord with ethical standards of 3R for laboratory animal.

Aim To investigate the effect of tetrameth-ylpyrazine(TMP)on neuroinflammation after cerebral ischemia and hypoxia via mannose-binding lectin(MBL).Methods Patients diagnosed with ischaemic stroke at Shanxi Provincial People's Hospital were in-cluded in the study,and their clinicopathological data,as well as blood and urine samples,were collected with the consent of the patients and their families.Using these biological samples,differential proteins and tar-gets were identified by proteomic analysis and subse-quently verified with animal experiments.The mice were divided into the sham,dMCAO,and TMP(10,20,40 mg·kg-1)treatment groups.After seven days of drug administration,the modified neurological sever-ity score(mNSS)was used to assess the neurological function.TTC staining was used to detect the volume of cerebral infarction.Motor function was evaluated be-haviourally,and ELISA was used to detect MASP1,sC5b-9,TNF-α,IL-6,and IL-1β.Western blot was used to determine the expression of relevant proteins,such as MBL2,MASP2,and C3.Results Compared with the sham group,the dMCAO group exhibited in-creased neurological impairment,which was signifi-cantly ameliorated by TMP treatment.The expression levels of MBL2,C3 and MASP2 were elevated in the dMCAO group and were reduced following TMP treat-ment.Additionally,the dMCAO group showed elevat-ed expression of inflammatory factors IL-1 β,IL-6 and TNF-α,which were then suppressed by TMP treat-ment.Conclusion TMP inhibits the inflammatory re-sponse after ischemia and hypoxia by regulating MBL,thus attenuating brain injury.

Nature killer(NK)cells are lymphocytes of the innate immune that play a significant role in aging through direct cell killing and secretion of cytokines.NK cells can delay the occurrence of age-related diseases and prolong lifespan by eliminating senescencent cells.Significant progress has been achieved in the research utilizing NK cells to improve aging.This review aims to summarize that the recent research on the mechanism of NK cells in the context of senescence, as well as the progress made in anti-senescence interventions through animal and clinical studies.Nevertheless, substantial challenges remain for the clinical application of NK cell-based anti-senescence therapies.

At present,the research and development of drugs in the central nervous system(CNS)field in China is progressing rapidly.In the process of CNS drug development,it is necessary to monitor the potential drug abuse as early as possible,and evaluate the drug dependence through comprehensive evaluation of pharmaceutical,non clinical and clinical evidence.At present,both European Medicines Agency(EMA)and Food and Drug Administration(FDA)have issued relevant guidelines to manage drugs with potential abuse,and China's National Medical Products Administration has also released the guidance of non-clinical drug dependence research.Therefore,in order to guide the development of CNS drugs,monitor the potential drug abuse,ensure patient medication safety,and guide clinical rational medication,On 28 September 2022,guidance of clinical drug dependence research was published.Clinical dependency assessment is an important part of the safety evaluation of drugs with abuse potential.Due to its special research purpose and evaluation requirements,its research process and data sources run through the entire clinical research.Analysis of relevant data generated throughout the clinical research process,evidence about drug clinical dependency is obtained.This article will introduce the background and key elements of this guidance.