Flap transplantation is a critical surgical strategy for the reconstruction of tissue defects caused by trauma, tumor resection, and congenital malformations, and its survival rate directly determines surgical efficacy and patient prognosis. Following transplantation, flaps inevitably undergo ischemia-reperfusion (I/R) injury, during which oxidative stress, inflammatory responses, and metabolic disturbances are intricately intertwined, ultimately leading to cellular injury and tissue necrosis. Recent studies have demonstrated that multiple forms of programmed cell death—including apoptosis, pyroptosis, ferroptosis, necroptosis, and PANoptosis—play central roles in flap I/R injury. The extensive crosstalk and molecular interactions among these pathways form a highly complex cell death network. Specifically, apoptosis is mediated by the imbalance of Bcl-2 family proteins and the activation of cysteine-dependent aspartate-specific protease (caspase) cascades; pyroptosis is driven by the NLRP3-caspase-1-GSDMD axis, resulting in membrane pore formation and the release of pro-inflammatory cytokines; ferroptosis is characterized by iron-dependent lipid peroxidation and dysfunction of glutathione peroxidase 4 (GPX4); necroptosis is triggered by the receptor-interacting serine/threonine-protein kinase 1 (RIPK1)-RIPK3-MLKL signaling complex, leading to membrane rupture; and PANoptosis represents an integrated form of inflammatory cell death that coordinates multiple death pathways. Importantly, these forms of programmed cell death are not independent but are interconnected through extensive signaling crosstalk. Key regulatory molecules, including caspase-8, reactive oxygen species (ROS), nuclear factor-κB (NF-κB), and nuclear factor erythroid 2-related factor 2 (Nrf2), collectively modulate the dynamic balance among these pathways. Therefore, the multidimensional interplay and spatiotemporal dynamics of programmed cell death constitute a fundamental pathological basis of flap I/R injury. This review systematically summarizes the latest advances in the mechanisms and interactions of various programmed cell death pathways in flap I/R injury, aiming to elucidate the underlying regulatory network. These insights may provide novel theoretical foundations for optimizing flap protection strategies, improving flap survival, and promoting tissue repair.

BACKGROUND:Flap transplantation technique is a commonly used surgical procedure for the treatment of severe tissue defects,but postoperative flap necrosis is easily triggered by ischemia-reperfusion injury.Therefore,it is still an important research topic to improve the survival rate of transplanted flaps. OBJECTIVE:To review the pathogenesis and latest treatment progress of flap ischemia-reperfusion injury. METHODS:CNKI,WanFang Database and PubMed database were searched for relevant literature published from 2014 to 2024.The search terms used were"flap,ischemia-reperfusion injury,inflammatory response,oxidative stress,Ca2+overload,apoptosis,mesenchymal stem cells,platelet-rich plasma,signaling pathways,shock wave,pretreatment"in Chinese and English.After elimination of irrelevant literature,poor quality and obsolete literature,77 documents were finally included for review. RESULTS AND CONCLUSION:Flap ischemia/reperfusion injury may be related to pathological factors such as inflammatory response,oxidative stress response,Ca2+overload,and apoptosis,which can cause apoptosis of vascular endothelial cells,vascular damage and microcirculation disorders in the flap,and eventually lead to flap necrosis.Studies have found that mesenchymal stem cell transplantation,platelet-rich plasma,signaling pathway modulators,shock waves,and pretreatment can alleviate flap ischemia/reperfusion injuries from different aspects and to varying degrees,and reduce the necrosis rate and necrosis area of the grafted flap.Although there are many therapeutic methods for skin flap ischemia/reperfusion injury,a unified and effective therapeutic method has not yet been developed in the clinic,and the advantages and disadvantages of various therapeutic methods have not yet been compared.Most of the studies remain in the stage of animal experiments,rarely involving clinical observations.Therefore,a lot of research is required in the future to gradually move from animal experiments to the clinic in order to better serve the clinic.

The Pharmacopeia of the People’s Republic of China 2025 Edition (referred to as the Chinese Pharmacopoeia 2025 Edition, ChP 2025) will be promulgated and implemented. This article introduces the process of development of ChP 2025 Edition (Volume Ⅱ), including the selection, the revision of general notices,the addition and revision of drug monographs, etc., and provides some analysis and examples to illustrate,which can facilitate the readers to understand and implement the ChP 2025 Edition (Volume Ⅱ).

Recent studies have shown that the physiological homeostasis of oral mucosal cells is regulated by the circadian clock.Dis-ruption or dysfunction of the circadian clock is closely associated with the development of oral squamous cell carcinoma(OSCC).Research based on the circadian clock offers a novel perspective on the pathogenesis and therapeutic strategies for OSCC.However,there is current-ly limited research on this topic,and people generally have insufficient understanding and recognition of the circadian clock.Given the complexity and challenges of circadian clock which is the fourth dimension of medical research,we organize relevant experts based on summarizing the current research results of circadian clock in the pathogenesis and precision diagnosis and treatment of OSCC,combining the scientific principles of the circadian clock's role and their long-term research experience,then summarizes and recommends the con-sensus opinions for the research of circadian clock in the pathogenesis mechanism and precision diagnosis and treatment of human OSCC,with the hope of providing guidance for the basic research and clinical application of circadian clock or circadian rhythm in the pathogene-sis mechanism and precision diagnosis and treatment of oral and maxillofacial squamous cell carcinoma.

Oropharyngeal squamous cell carcinoma(OPSCC)is a malignant tumor originating from the squamous epithelium of the oro-pharyngeal mucosa,accounting for more than 90％of oropharyngeal malignancies.In recent years,human papillomavirus(HPV)infec-tion has become one of the primary etiological factors of oropharyngeal squamous carcinoma.The incidence of HPV-associated oropharyn-geal squamous carcinoma has been rising annually,with a noticeable trend toward younger populations,posing a significant threat to hu-man health.Due to the distinct biological behavior and clinical characteristics of HPV-associated oropharyngeal squamous carcinoma com-pared to its non-HPV-related counterpart,the diagnostic and treatment strategies for oropharyngeal squamous carcinoma have undergone substantial changes.Prevention and screening for oropharyngeal squamous carcinoma are of critical importance.The diagnostic and treat-ment process involves multi-disciplinary collaboration,including oral and maxillofacial surgery,otolaryngology,head and neck surgery,oncology,radiology and pathology.Based on evidence from clinical practice,a comprehensive,integrated diagnostic and therapeutic ap-proach has been established,centered around the concept of"prevention,screening,diagnosis,treatment,and rehabilitation",covering the entire patient lifecycle and providing a valuable reference for clinical practice.

Objective:To analyze the efficacy of endovascular treatment for venous outflow tract obstruction after liver transplantation.Methods:A retrospective analysis was conducted on the data of 7 patients with venous outflow tract obstruction after liver transplantation admitted to Beijing Friendship Hospital, Capital Medical University from November 2020 to December 2024. Among them, there were 5 males and 2 females, with the age of (22.3±8.1) years. The primary diseases included 2 cases of Budd-Chiari syndrome, 1 case of hepatic veno-occlusive disease, 1 case of portal veno-hepatic sinus vascular disease, 1 case of ornithine carbamoyltransferase deficiency, 1 case of primary biliary cirrhosis, and 1 case of autoimmune cirrhosis. Analyze the patient's clinical manifestations, obstruction of venous outflow tract, hemoglobin levels within one week before and one week after the operation, endovascular treatment conditions, and intraoperative complications such as abdominal hemorrhage and vascular injury. Ultrasound was used to measure the depth of ascites and pleural effusion. All patients were followed up immediately after the operation through phone calls or follow-up visits. The clinical symptoms, abdominal vascular ultrasound, enhanced CT and survival status of the patients were followed up.Results:All 7 patients were diagnosed with venous outflow tract obstruction by intraoperative angiography, including 1 cases of inferior vena cava obstruction, 2 cases of hepatic vein obstruction, and 4 cases of vena cava combined with hepatic vein obstruction. A total of 12 endovascular treatments were performed on 7 patients. Among them, 4 patients received balloon dilation and angioplasty once, 1 patient received balloon dilation and angioplasty twice, 1 patient underwent hepatic vein stent implantation after 2 hepatic vein balloon dilation and angioplasty, and 1 patient underwent intrahepatic portosystemic shunt via jugular vein after 2 hepatic vein balloon dilation and angioplasty. The abdominal distensionof the patients were all relieved after the operation, the ascites and pleural effusion decreased, and the edema symptoms of the lower extremities disappeared. There were no intraoperative complications. The preoperative hemoglobin of 7 patients was (113.4±34.0) g/L, and the postoperative hemoglobin was (126.6±34.8) g/L, which increased significantly compared with that before the operation, and the difference was statistically significant ( t=-0.71, P=0.038). Seven patients were followed up for 6 to 24 months, with a median of 12 months. None of them had obvious symptoms including abdominal distension. Abdominal ultrasound and CT indicated that the blood flow of the transplanted liver was unobstructed, and no patient died. Conclusion:Venous outflow tract obstruction after liver transplantation can cause severe symptoms. Endovascular treatment is an effective treatment for venous outflow tract obstruction after liver transplantation.

Flap surgery is a complex surgical procedure that has become an effective method for the treatment of many diseases and traumas.Flap survival is closely related to a variety of factors including cellular autophagy,oxidative stress,inflammatory response,mesenchymal stem cells(MSCs)function,and vascular regeneration.Cellular autophagy maintains intracellular homeostasis and plays a key role in reducing oxidative stress and inflammation and promoting injury repair.Excessive oxidative stress and inflammatory responses pose a threat to flaps,affecting their survival and successful transplantation.Endothelial cells are involved in vascu-lar regeneration through proliferation,migration,and production of angiogenic factors,and vascular endothelial growth factor directly promotes blood vessel formation and maintains endothelial cell function.MSCs play an important role in promoting flap survival and tissue repair due to their unique biological properties and multiple mechanisms of action.The multiple roles played by cellular autophagy,oxidative stress,inflammatory response,MSCs function,and vascular regeneration in influencing postoperative flap survival are hereby elaborated.The aim is to provide a basis for the clinical application of regulating the above factors to improve postoperative flap survival,improve the success rate of flap surgery,reduce complications,and bring more hope for the recovery and quality of life of patients.

The Pharmacopeia of the People's Republic of China 2025 Edition(referred to as the Chinese Pharmaco-poeia 2025 Edition,ChP 2025)will be promulgated and implemented.This article introduces the process of devel-opment of ChP 2025 Edition(Volume Ⅱ),including the selection,the revision of general notices,the addition and revision of drug monographs,etc.,and provides some analysis and examples to illustrate,which can facilitate the readers to understand and implement the ChP 2025 Edition(Volume Ⅱ).

The mortality rates are significantly elevated with the rapid progression of acute liver failure in the absence of timely diagnosis and treatment. Liver transplantation is an effective therapeutic approach that can halt disease progression, but transplantation timing is a crucial factor affecting prognosis. Patients with acute liver failure should be promptly transferred to hospitals equipped for liver transplantation while simultaneously preparing for the procedure during the course of treatment to avoid missing the opportunity to save lives when the condition suddenly worsens. Auxiliary liver transplantation preserves the patient's native liver while transplanting a new liver. Therefore, patients are expected to gradually reduce immunosuppressants following the regeneration of the autologous liver, so avoiding the problem of lifelong use of immunosuppressants. This is also a unique advantage, offering benefits to patients undergoing auxiliary liver transplantation therapy for acute liver failure, while simultaneously presenting challenges for clinicians in terms of technical skill and comprehensive management.

Objective:To evaluate the safety and efficacy of using small and ultra-small sized grafts for in situ auxiliary liver transplantation in the treatment of portal hypertension.Methods:A prospective single-arm cohort study was conducted. Patients who underwent liver transplantation at Beijing Friendship Hospital from December 2014 to July 2025 were included. Intraoperative portal vein pressure was routinely monitored, with the target regulation for portal vein blood flow set at<15 mmHg (1 mmHg=0.133 kPa) and follow-up continued until September 2025. The primary endpoints were the patient's status and graft survival. The secondary endpoints were small-for-size syndrome and perioperative complications. The small-for-size syndrome was graded according to the 2023 International Liver Transplantation Society consensus statement.Results:A total of 33 cases were enrolled. Among them, 22 had ultra-small size grafts, 11 had small-size grafts, 28 had living donor grafts, and five had split grafts. The graft-to-recipient weight ratio in living donor liver transplantation was 0.31%～0.79%, while in split liver transplantation it was 0.45%～1.02%. Intraoperative portal vein pressure of ≥15 mmHg was observed in 11 cases, who underwent portal vein blood flow adjustment via splenic artery ligation (2 cases), partial splenectomy (8 cases), and/or restrictive portocaval shunting (1 case), after which all patients achieved the target portal vein pressure. All cases completed at least one month of follow-up, with 28 cases following for more than one year, and the median follow-up period was 36.5 months. Early-stage postoperative small-for-size syndrome occurred in eight cases (24.2%, 8/33), all classified as grade A, with improvements following supportive treatment. Severe complications (Clavien-Dindo≥Ⅲ) occurred in three cases (9.1%, 3/33). The one-year survival rate was 92.9% (26/28). The overall survival rate at the end of follow-up was 90.9% (30/33). No patients experienced graft loss or death due to small-for-size syndrome. Graft tissue tested negative for hepatitis B core antibody and covalently closed circular DNA, and hepatitis B surface antigen seroconversion was achieved following second-stage residual liver resection and under a combined strategy of potent nucleos(t)ide analogs and hepatitis B immunoglobulin in ten cases of hepatitis B-related disease.Conclusions:With standardized portal vein blood flow monitoring and individualized portal vein blood flow adjustment, in situ auxiliary liver transplantation can safely and effectively use small and even ultra-small sized grafts, thereby significantly expanding graft sources and ensuring donor and recipient safety. These findings warrant further validation and promotion in multicenter controlled studies.