1.Immune Checkpoint Inhibitor-Related Immune Cystitis: A Case Report
Jing YU ; Ling LI ; Wenfang CHEN ; Qiong WEN ; Wei CHEN
Medical Journal of Peking Union Medical College Hospital 2026;17(2):396-402
Immune checkpoint inhibitors (ICIs) are widely used in the treatment of malignant tumors, and their related immune-related adverse events (irAEs) have attracted increasing attention. This study reports the diagnosis and treatment process of a case of immune cystitis in a patient with hepatobiliary tract malignant tumor after treatment with pembrolizumab. The patient was admitted to the hospital due to frequent urination, urgency of urination and dysuria for 1 month. Previous repeated anti-infection treatments were ineffective. Combined with medical history, laboratory tests, imaging findings, cystoscopy and pathological results, the patient was clinically diagnosed with ICIs-associated immune cystitis (Pembrolizumab) ultimately. The patient's symptoms significantly improved after treatment with glucocorticoids. This case reindicates that clinicians need to improve awareness of ICI-related urinary system irAEs. Early identification and timely intervention can significantly improve patient prognosis.
2.The Potential and Challenges of Temporal Interference Stimulation in Chronic Pain Management
Hao-Qing DUAN ; Yu-Qi GOU ; Ya-Wen LI ; Li HU ; Xue-Jing LÜ
Progress in Biochemistry and Biophysics 2026;53(2):369-387
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.
3.The Potential and Challenges of Temporal Interference Stimulation in Chronic Pain Management
Hao-Qing DUAN ; Yu-Qi GOU ; Ya-Wen LI ; Li HU ; Xue-Jing LÜ
Progress in Biochemistry and Biophysics 2026;53(2):369-387
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.
4.The Role of FASN in Tumors and Its Targeted Therapy
Wen-Jing JIANG ; Ruo-Xi ZHANG ; Yu-Qing TAI ; Ya-Wen SUN ; Xi-Yu ZHANG ; Xiao LI
Progress in Biochemistry and Biophysics 2026;53(4):920-935
Malignant tumors represent a major threat to global health. Conventional anti-tumor pharmacotherapy often encounters challenges such as drug resistance, highlighting an urgent need for the development of novel therapeutic strategies. Fatty acid synthase (FASN), the key enzyme catalyzing de novo fatty acid synthesis, is subject to precise regulation at multiple levels, including transcriptional control, various post-translational modifications such as ubiquitination and phosphorylation, as well as modulation by diverse signaling pathways. Recent studies have revealed that FASN is aberrantly overexpressed in various malignant tumors and is closely associated with tumor progression and poor patient prognosis. FASN is a homodimer composed of seven functional domains that catalyzes the NADPH-dependent condensation of acetyl-CoA and malonyl-CoA to generate saturated fatty acids, primarily palmitic acid. Its stability is regulated by multiple ubiquitin ligases and deubiquitinating enzymes. Additionally, FASN is subject to upstream regulation via neural precursor cell-expressed developmentally downregulated 8 (Nedd8) modification and the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway, thereby establishing a metabolic-signaling positive feedback loop. As a core executor of metabolic reprogramming, FASN promotes tumorigenesis through dual mechanisms. First, its fatty acid synthesis product, palmitate, participates in membrane phospholipid synthesis, lipid raft formation, and protein palmitoylation, thereby activating several key oncogenic signaling pathways, including PI3K/AKT/mTOR, wingless-type MMTV integration site family member (Wnt)/β‑catenin, and signal transducer and activator of transcription 3 (STAT3)/matrix metalloproteinase (MMP), leading to tumor development and progression. Second, FASN plays a pivotal role in modulating the anti-tumor functions of immune cells and remodeling the tumor immune microenvironment. Specifically, FASN enhances immune checkpoint inhibition by inducing programmed death-ligand 1 (PD-L1) palmitoylation, suppresses the activation of cytotoxic T lymphocytes and natural killer cells, and promotes the polarization of M2-type macrophages, consequently facilitating tumor immune evasion and malignant progression. Precisely due to its significant overexpression in tumor cells, its critical functional role, and its differential expression compared to normal cells, FASN has emerged as a highly promising target for anti-tumor drug development. Highly selective small-molecule inhibitors, notably represented by TVB-2640, have advanced to clinical trial stages and demonstrated favorable anti-tumor activity. Furthermore, the combination of FASN inhibitors with other chemotherapeutic agents or targeted drugs can overcome the limitations of monotherapy through synergistic effects or by resensitizing tumor cells to conventional drugs, achieving a “1+1>2” therapeutic outcome. With the advancement of modern traditional Chinese medicine (TCM), numerous active ingredients derived from TCM have been confirmed to exert anti-tumor effects by modulating FASN-related pathways. This integrated approach leverages the precision of Western medicine while simultaneously harnessing the holistic regulatory benefits of TCM to alleviate the side effects of radiotherapy and chemotherapy. Despite the promising prospects of FASN-targeted therapies, challenges remain, including tumor cell metabolic plasticity, tumor context-dependent responses, and heterogeneity. This review systematically summarizes the molecular structure, physiological functions, and mechanisms of FASN in tumorigenesis, as well as recent advances in targeted therapies. Future directions—including the precise identification of responsive patient populations using spatial transcriptomics, the development of novel combination regimens, and the active exploration of integrative strategies combining traditional Chinese and Western medicine—will facilitate the clinical translation of FASN-targeted therapies and open new avenues for improving the quality of life and prognosis of cancer patients.
5.Necroptosis in Exercise-induced Skeletal Muscle Damage: Roles and Regulatory Mechanisms
Zhi-Fei KE ; Wen-Jing SONG ; Yun-Feng DONG ; Hua-Yu SHANG
Progress in Biochemistry and Biophysics 2026;53(7):1884-1895
Exercise-induced muscle damage (EIMD) is a frequent form of skeletal muscle microdamage that occurs after high-intensity, prolonged, or unaccustomed exercise, especially exercise dominated by eccentric contractions. It is commonly characterized by delayed-onset muscle soreness, transient loss of muscle strength, local inflammation, structural disruption of myofibers, and delayed functional recovery. Although mild EIMD may serve as a stimulus for training adaptation, excessive or insufficiently recovered muscle damage can impair exercise performance, disturb training continuity, and reduce participation in physical activity. Therefore, clarifying the molecular mechanisms that underlie the initiation, amplification, and resolution of EIMD is important for optimizing athletic training, improving post-exercise recovery, and guiding evidence-based public fitness practice. Necroptosis is a regulated form of programmed cell death mediated primarily by the receptor-interacting protein kinase (RIPK) 1/RIPK3/mixed lineage kinase domain-like protein (MLKL) signaling axis. Recent studies have shown that necroptosis is closely involved in tissue injury, sterile inflammation, and repair remodeling. However, whether necroptosis acts as an initiating driver, a secondary damage amplifier, or an adaptive signal required for repair after EIMD remains unclear. This review aimed to summarize the potential role of necroptosis in EIMD and to establish a mechanistic framework linking regulated cell death, inflammatory amplification, immune regulation, and skeletal muscle repair. Relevant studies concerning EIMD, necroptosis, RIPK1/RIPK3/MLKL signaling, damage-associated molecular patterns (DAMPs), inflammatory responses, immune cell recruitment, extracellular matrix remodeling, and muscle regeneration were reviewed and integrated. On this basis, the possible temporal and functional involvement of necroptosis in different phases of EIMD was analyzed. The main evidence summarized in this review suggests that EIMD is not merely a consequence of primary mechanical disruption. Instead, it develops through a dynamic sequence that includes sarcolemmal instability, calcium overload, mitochondrial dysfunction, oxidative stress, inflammatory mediator production, immune cell infiltration, necrotic tissue clearance, and regeneration-associated remodeling. Necroptosis may participate in this process through at least two interconnected mechanisms. First, in the early or progressive phase of EIMD, activation of the RIPK1/RIPK3/MLKL signaling axis may promote MLKL phosphorylation and plasma membrane permeabilization, leading to the release of DAMPs such as high-mobility group box 1, ATP, mitochondrial DNA, and other intracellular components. These signals may activate innate immune pathways, amplify inflammatory cytokine production, and enhance the recruitment of neutrophils and macrophages, thereby aggravating secondary inflammation and extending muscle fiber injury. Second, during the resolution and repair phases, necroptosis-related signaling may also contribute indirectly to the formation of a regenerative microenvironment. By influencing the clearance of necrotic debris, the recruitment and phenotypic transition of immune cells, and the remodeling of extracellular matrix components, necroptosis may affect satellite cell activation, myogenic repair, and the eventual structural and functional recovery of injured skeletal muscle. Thus, the biological effect of necroptosis in EIMD may be context dependent rather than uniformly harmful. Its outcome may depend on exercise intensity, the extent of tissue damage, the timing of pathway activation, the involved cell types, inflammatory status, training background, age, and metabolic condition. In conclusion, necroptosis may represent an important molecular link between skeletal muscle injury, sterile inflammation, and tissue repair after damaging exercise. It may exert a dual role in EIMD by amplifying secondary damage while also contributing to repair coordination under appropriate temporal and microenvironmental conditions. Future studies should determine the activation pattern of RIPK1/RIPK3/MLKL signaling after different exercise protocols, identify the major cell populations undergoing necroptosis in injured skeletal muscle, and examine whether targeted modulation of necroptosis can reduce excessive inflammation without impairing necessary regenerative responses. This review provides a theoretical basis for understanding the pathogenesis of EIMD and for developing targeted strategies to improve skeletal muscle recovery after exercise-induced injury.
6.Chemical constituents from the sticks and leaves of Croton cascarilloides and their biological activities
Yu-jie LÜ ; Hui-qin CHEN ; Hao WANG ; Jing-zhe YUAN ; Wen-li MEI ; Shou-bai LIU ; Hao-fu DAI
Chinese Traditional Patent Medicine 2025;47(7):2249-2254
AIM To study the chemical constituents from the sticks and leaves of Croton cascarilloides Raeusch.and their biological activities.METHODS The 95%ethanol extract from the sticks and leaves of C.cascarilloides was isolated and purified by MCI,silica gel,Sephadex LH-20 and semi-preparative HPLC,then the structures of obtained compounds were identified by physicochemical properties and spectral data.LPS-induced NO RAW264.7 cell model induced by LPS was used to evaluate its anti-inflammatory activity in vitro.GES-1 injury model induced by taurocholic acid was used to screen the gastric mucosal protection activity.RESULTS Fourteen compounds were isolated and identified as bullatantriol(1),(-)-boscialin(2),(+)-dehydrovomifoliol(3),3-(hydroxylacetyl)-indole(4),pinoresinol(5),3,7-dimethyl-octa-1,7-diene-3,6-ol(6),(+)-syringaresinol(7),curcasinlignan B(8),cleomiscosin C(9),cleomiscosinD(10),2,6-dimethyl-octa-1,7-dien-3,6-diol(11),vanillin(12),vanillic acid(13),methyl vanillate(14).Compound 4 had certain anti-inflammatory activity,with IC50 values of 73.62 μmol/L.The protective rates of 25 μmol/L compounds 1-4,6,9-12 and 14 on gastric mucosal epithelial cells were 30.07%,34.18%,23.91%,30.92%,17.51%,19.69%,31.76%,22.46%,30.56%and 14.49%,respectively.CONCLUSION Compounds 1-14 are isolated from this plant for the first time.Compound 4 shows anti-inflammatory activity,1-4,6,9-12 and 14 show different degrees of gastric mucosal epithelial cell protective activity.
7.Preparation of borneol-menthol eutectic mixture-loaded nanoemulsion gel of tetramethylpyrazine
Jing WEN ; Jun-song NIU ; Yu-zhen WU ; Jie DENG ; Nan LI
Chinese Traditional Patent Medicine 2025;47(8):2522-2529
AIM To prepare the borneol-menthol eutectic mixture-loaded nanoemulsion gel of tetramethylpyrazine.METHODS The equilibrium solubilities of tetramethylpyrazine in different oil phases,emulsifiers and co-emulsifiers were determined,after which compatibility experiment was performed,and pseudo-ternary phase diagram was drawn.With Km value,oil phase proportion and water phase consumption as influencing factors,particle size,PDI and saturated drug loading as evaluation indices,the formulation was optimized by central composite design-response surface method.The drug-loaded nanoemulsion was dispersed into carbomer 940 gel matrix to prepare nanoemulsion gel,then the physicochemical properties,in vitro drug release and transdermal absorption properties were investigated.RESULTS The optimal formulation was determined to be 3.31∶6.16∶1.56∶88.97 for eutectic mixture-EL-40-1,2-propylene glycol-water ratio,the particle size,PDI and saturated drug loading were 37.85 nm,23.04 and 5.82 mg/g,respectively.The obtained white,semi-solid nanoemulsion gel demonstrated the average pH value and viscosity of 6.68±0.07 and(289.69±1.06)mPa·s,respectively,whose in vitro drug release accorded with Higuchi equation,and the accumulative permeability per unit area was(2 048.23±55.6)μg/cm2 within 24 h,which were 3.72 and 1.21 times higher than those of hydrogel and aqueous solution,respectively.CONCLUSION The borneol-menthol eutectic mixture-loaded nanoemulsion gel of tetramethylpyrazine meets preparation requirements,thus can achieve the effective transdermal delivery of raw medicine.
8.Differences in mercury dissolution from HgS-containing traditional medicines under simulated gastrointestinal conditions
Ming ZHANG ; Yuan-can XIAO ; Jing ZHAO ; Hai-ying TONG ; Xiao-yu WANG ; Wen-bin ZHOU ; Hong-tao BI ; Li-xin WEI
Chinese Traditional Patent Medicine 2025;47(8):2607-2611
AIM To investigate the variations in mercury dissolution from HgS-containing traditional medicines in three kinds of simulated gastrointestinal dissolution media.METHODS 39 batches of 15 types of HgS-containing traditional medicines were collected,total mercury content and dissolved mercury concentrations in simulated gastric fluid,simulated intestinal fluid,and L-cysteine-containing simulated intestinal fluid were measured.The maximum daily intake of total mercury and soluble mercury was calculated based on the maximum daily clinical dosage.RESULTS Among the 15 types of medicines,the maximum daily intake of total mercury varied by 156 times,the daily intake of soluble mercury varied by 3 502 times in simulated gastric fluid,313 times in simulated intestinal fluid,and 10 663 times in L-cysteine-containing simulated intestinal fluid,approximately.CONCLUSION For the 15 types of HgS-containing traditional medicines,the daily maximum intake of soluble mercury showed greater variations than that of total mercury.Soluble mercury concentration is more closely correlated with intestinal absorption of mercury and thus represents a more rational quality control indicator for HgS-containing traditional medicines.
9.Chemical constituents from the leaves of Drynaria fortunei and their antioxidant activity
Xin CHEN ; Jia-cheng WANG ; Yan-yan LIU ; Yong-wen ZHANG ; Ze-jing MU ; Hai-yan ZHANG ; Yu PENG ; Tong-lin WAN ; Yong-hong LIANG
Chinese Traditional Patent Medicine 2025;47(8):2587-2592
AIM To study the chemical constituents from the leaves of Drynaria fortunei(Kunze)J.Sm.and their antioxidant activity.METHODS ODS-AG-HG,Sephadex LH-20 and semi-preparative HPLC were used for separation and purification,then the structures of obtained compounds were identified by physicochemical properties and spectral data.The antioxidant activity was determined by DPPH mothod.RESULTS Fifteen compounds were isolated and identified as kaempferol-3-O-neohesperidoside(1),dihydrodehydrodiconiferyl alcohol(2),kaempferol-3,7-di-O-α-L-rahmnoside(3),astragalin(4),loliolid(5),trichothecene analogue(6),2,2-[bis-4-(2,3-dihydroxypropoxy)phenyl]propane(7),maculatin(8),trichothecin(9),4-[(Z)-but-2-enoyloxy]-8-chloro-12-hydroxy-7,13-epoxytrichothec-9-ene(10),8-deoxy-trichotecin(11),β-sitosterol(12),daucosterol(13),afzelin(14),samwinol(15).The IC50 values of the leaf and rhizome extracts against DPPH free radicals were(0.072±0.005),(0.287±0.012)mg/mL,respectively.CONCLUSION Compounds 1,2,5-11,15 are isolated from this plant for the first time.The leaves of D.fortunei exhibit strong antioxidant activity.
10.Highly Sensitive Detection of Water in Organic Solvents Using Pyrene-Phenol-based Fluorescent Probe
Jing LIANG ; Yan-Li WANG ; Cui-Wen JIANG ; Xiao-Chuan HUANG ; Li TANG ; Tao LI ; Yu YA ; De-Jiao NING ; Li-Ping XIE ; Fei-Yan YAN
Chinese Journal of Analytical Chemistry 2025;53(6):894-902,中插1-中插5
A pyrene-phenol-based fluorescent probe PyP which showed typical intramolecular charge transfer(ICT)and monomer-excimer activities was synthesized by using pyrene carboxaldehyde hydrazone and 4-tert-butyl-2,6-diformylphenol as the raw materials.The effects of solvents on PyP were studied,and the results showed that the color of protic polar solvents(Ethanol,N,N-dimethylformamide,methanol and H2O)were successfully identified.Based on the solvent polarity-regulated PyP monomer-excimer switching,the rapid and highly sensitive ratiometric probe,"Turn-off"and"Turn-on"multimodal probes were established for detection of trace water content in organic solvents(Dimethyl sulfoxide,N,N-dimethylformamide,ethanol and methanol),with detection limits(3σ/k)of 0.0021%,0.046%,0.062%and 0.024%.The method was successfully used to detect water content in dimethyl sulfoxide,N,N-dimethy lformamide,ethanol and methanol commercial organic solvents,with recoveries ranging from 97.2%to 108.0%.The developed method showed good accuracy and stability,and had good application prospect.

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