Circadian rhythm is an endogenous biological clock mechanism that enables organisms to adapt to the earth’s alternation of day and night. It plays a fundamental role in regulating physiological functions and behavioral patterns, such as sleep, feeding, hormone levels and body temperature. By aligning these processes with environmental changes, circadian rhythm plays a pivotal role in maintaining homeostasis and promoting optimal health. However, modern lifestyles, characterized by irregular work schedules and pervasive exposure to artificial light, have disrupted these rhythms for many individuals. Such disruptions have been linked to a variety of health problems, including sleep disorders, metabolic syndromes, cardiovascular diseases, and immune dysfunction, underscoring the critical role of circadian rhythm in human health. Among the numerous systems influenced by circadian rhythm, the skin—a multifunctional organ and the largest by surface area—is particularly noteworthy. As the body’s first line of defense against environmental insults such as UV radiation, pollutants, and pathogens, the skin is highly affected by changes in circadian rhythm. Circadian rhythm regulates multiple skin-related processes, including cyclic changes in cell proliferation, differentiation, and apoptosis, as well as DNA repair mechanisms and antioxidant defenses. For instance, studies have shown that keratinocyte proliferation peaks during the night, coinciding with reduced environmental stress, while DNA repair mechanisms are most active during the day to counteract UV-induced damage. This temporal coordination highlights the critical role of circadian rhythms in preserving skin integrity and function. Beyond maintaining homeostasis, circadian rhythm is also pivotal in the skin’s repair and regeneration processes following injury. Skin regeneration is a complex, multi-stage process involving hemostasis, inflammation, proliferation, and remodeling, all of which are influenced by circadian regulation. Key cellular activities, such as fibroblast migration, keratinocyte activation, and extracellular matrix remodeling, are modulated by the circadian clock, ensuring that repair processes occur with optimal efficiency. Additionally, circadian rhythm regulates the secretion of cytokines and growth factors, which are critical for coordinating cellular communication and orchestrating tissue regeneration. Disruptions to these rhythms can impair the repair process, leading to delayed wound healing, increased scarring, or chronic inflammatory conditions. The aim of this review is to synthesize recent information on the interactions between circadian rhythms and skin physiology, with a particular focus on skin tissue repair and regeneration. Molecular mechanisms of circadian regulation in skin cells, including the role of core clock genes such as Clock, Bmal1, Per and Cry. These genes control the expression of downstream effectors involved in cell cycle regulation, DNA repair, oxidative stress response and inflammatory pathways. By understanding how these mechanisms operate in healthy and diseased states, we can discover new insights into the temporal dynamics of skin regeneration. In addition, by exploring the therapeutic potential of circadian biology in enhancing skin repair and regeneration, strategies such as topical medications that can be applied in a time-limited manner, phototherapy that is synchronized with circadian rhythms, and pharmacological modulation of clock genes are expected to optimize clinical outcomes. Interventions based on the skin’s natural rhythms can provide a personalized and efficient approach to promote skin regeneration and recovery. This review not only introduces the important role of circadian rhythms in skin biology, but also provides a new idea for future innovative therapies and regenerative medicine based on circadian rhythms.

OBJECTIVE: To summarize the methods of ankle hinge position design in the correction of clubfoot deformity by Ilizarov method, and to explore its application value in the prevention of ankle dislocation. METHODS: A retrospective study was conducted including 28 patients with rigid clubfoot deformity (34 feet) who met the selection criteria and admitted between September 2021 and December 2024. There were 19 males and 9 females with an average age of 31.8 years (range, 19-47 years). According to Dimeglio classification, there were 21 feet of degree Ⅲ and 13 feet of degree Ⅳ. The causes were traumatic sequelae in 9 cases, congenital foot deformity in 15 cases, spina bifida sequelae in 1 case, peripheral neuropathy in 1 case, and cerebral palsy sequelae in 2 cases. The malformation lasted from 6 to 46 years, with an average of 29.3 years. All patients were treated with Ilizarov circular external fixator, and the hinge position of ankle joint was planned according to the standard lateral X-ray film of foot and ankle and the principle of Ilizarov limb deformity correction center of rotation angulation (CORA) before operation. The 2008 International Clubfoot Study Group (ICFSG) scoring system was used to evaluate the efficacy. RESULTS: The deformity of rigid clubfoot was completely corrected in all patients, and the patients could walk with plantar weight-bearing, and the ankle weight-bearing walking significantly improved when compared with that before operation. There was no complication such as ankle dislocation, talus impact or extrusion, local skin necrosis, needle tract infection, or numbness of extremities during the correction process. All patients were followed up 5-39 months, with an average of 18.1 months. At last follow-up, according to the ICFSG scoring system, 23 feet were excellent, 10 feet were good, and 1 foot was fair, and the excellent and good rate was 97%. CONCLUSION Designing the position of the ankle hinge according to the principle of CORA can effectively avoid ankle dislocation, talus impingement, tibiotalar joint extrusion, and other ankle adverse events in the process of correcting clubfoot deformity, which has good application value in clinical practice.
Humans ; Male ; Female ; Clubfoot/diagnostic imaging* ; Ilizarov Technique/instrumentation* ; Adult ; Retrospective Studies ; External Fixators ; Ankle Joint/diagnostic imaging* ; Middle Aged ; Joint Dislocations/prevention & control* ; Treatment Outcome ; Young Adult

OpenSim is an open source, free motion simulation and gait analysis software, which can be used to dynamically simulate and analyze the complex motion of the human body, and is widely used in human biomechanical research. Since OpenSim can analyze multi-dimensional motion data such as muscle strength, joint torque, and muscle synergistic activation during human movement, it can be used to study the biomechanical mechanism of musculoskeletal imbalance diseases and various treatment methods in TCM orthopedics, and has a broad application prospect in the field of TCM orthopedics. By the analysis of the basic characteristics, elements, analysis process, and application prospects of OpenSim, it is concluded that OpenSim musculoskeletal model has a large application space in the field of traditional Chinese medicine orthopedic, which is helpful to explain the pathogenesis and mechanism of diseases, and promote the precision diagnosis and treatment of orthopedics diseases;the application of OpenSim musculoskeletal model can solve the problem that the previous research paid attention to the bone malalignment and not enough attention to the tendon, and provide a new method for the research of orthopedic diseases. At present, there are still problems in the promotion and application of OpenSim, such as large equipment requirements and high operation threshold. Therefore, multidisciplinary cooperation, clinical research, and data sharing are the basic research strategies in this field.
Humans ; Biomechanical Phenomena ; Orthopedics ; Traumatology ; Software ; Medicine, Chinese Traditional ; Musculoskeletal System ; Models, Biological

OBJECTIVE: To investigate the biomechanical characteristics of retrograde tibial nailing (RTN) and distal tibial L-shaped plating in the internal fixation of distal tibial fractures. METHODS: Fourteen fresh adult tibia specimens were selected, comprising 7 males and 7 females aged from 34 to 55 years old. The specimens were randomly divided into experimental group and control group by numerical table method with 7 specimens in each group. RTN was used for internal fixation of distal tibial fractures in the experimental group, and L-shaped plate was used for internal fixation of distal tibial fractures in the control group. The axial compression properties of the two groups of specimens were tested under the pressure of 100, 200, 300, 400, and 500 N after operation, and torsional resistance at torque levels of 1.0, 2.0, 3.0, 4.0, 5.0 N·m. The anti-fatigue performance of the specimens was tested at 500 N pressure for 3 000 and 10 000 cycles. X-ray fluoroscopy was performed to observe whether the the internal fixator was deformed and whether the screw was loosened or broken. RESULTS: When the pressure was 400 N and 500 N, the axial compression displacement of the experimental group was (1.11±0.06) mm and (1.24±0.05) mm, which were smaller than those of the control group (1.21±0.08) mm and (1.37±0.11) mm, and the differences were statistically signific (P<0.05). Under the pressure of 500 N, the axial compression stiffness of the experimental group was (389.24±17.79) N·mm^-1, which was significantly higher than that of the control group (362.37±14.44) N·mm^-1(P<0.05). When the torque was 4 and 5 N·m, the torsion angles of the experimental group were (2.97±0.23) ° and (3.41±0.17) °, which were smaller than those of the control group (3.31±0.28) ° and (3.76±0.20) °, and the differences were statistically significant (P<0.05). When the torque was 5 N·m, the torsional stiffness of the experimental group was (1.48±0.07) N·m per degree, which was higher than that of the control group (1.36±0.06) N·m per degree, and the difference was statistically significant (P<0.05). For the intragroup comparison of fatigue resistance, the differences in axial compression displacement between the two groups were not statistically significant at 3 000 and 10 000 cycles (all P>0.05). When 3 000 times and 10 000 times of compression, the axial compression displacement of the experimental group was (1.38±0.08), (1.43±0.07) mm, which was smaller than that of the control group (1.51±0.10), (1.54±0.08) mm, the differences were statistically significant (P<0.05). In the experimental group, no screw loosening, fracture or internal fixation deformation was found, while in the control group, locking screw loosening occurred in 2 models after 10 000 pressures. CONCLUSION The biomechanical performance of RTN is obviously better than that of the distal tibial L-shaped plate, which provides biomechanical data support for the clinical application of RTN.
Humans ; Female ; Male ; Adult ; Tibial Fractures/physiopathology* ; Middle Aged ; Biomechanical Phenomena ; Bone Plates ; Fracture Fixation, Internal/instrumentation* ; Bone Nails ; Tibia/surgery*

OBJECTIVES: To identify risk factors for recurrent plastic bronchitis (PB) among children with Mycoplasma pneumoniae pneumonia (MPP). METHODS: The clinical data of children with MPP complicated by PB who underwent bronchoscopy at Gansu Province Maternity and Child Health Hospital between July 2023 and January 2025 were retrospectively analyzed. Patients were grouped into a single-episode PB group and a recurrent PB group according to the number of PB episodes. Multivariable logistic regression was used to identify risk factors for recurrent PB. Receiver operating characteristic (ROC) curve analysis was used to assess the diagnostic performance of individual and combined predictors. RESULTS: A total of 264 children were included; 188 (71.2%) had a single episode of PB and 76 (28.8%) had recurrent PB. Multivariable logistic regression analysis showed that decreased serum albumin, atelectasis, and fever persisting beyond 72 hours after the initial bronchoscopy were significantly associated with recurrent PB (all P<0.05). The combination of these predictors yielded a sensitivity of 82.9%, specificity of 61.7%, and an area under the ROC curve of 0.777 (95%CI: 0.714-0.839), outperforming any single predictor (P<0.05). CONCLUSIONS In children with MPP complicated by PB, decreased serum albumin, the presence of atelectasis, and fever persisting beyond 72 hours after the initial bronchoscopy are associated with an increased risk of PB recurrence. In such cases, early repeat or multiple bronchoscopic interventions should be considered.
Humans ; Pneumonia, Mycoplasma/complications* ; Male ; Female ; Risk Factors ; Recurrence ; Child, Preschool ; Bronchitis/etiology* ; Child ; Retrospective Studies ; Logistic Models ; Infant ; ROC Curve ; Adolescent

Recent clinical trials have demonstrated a protective effect in using traditional Chinese medicine Tongxinluo (TXL) capsule to treat atherosclerosis. However, clinical evidence of the effects of TXL treatment on coronary plaque vulnerability is unavailable. In response, we developed this study to investigate the hypothesis that on the basis of statin therapy, treatment with TXL capsule may stabilize coronary lesions in patients with acute coronary syndrome (ACS). The TXL-CAP study was an investigator-initiated, randomized, double-blind clinical trial conducted across 18 medical centers in China. Patients with ACS aging from 18 to 80 years old who had a non-intervened coronary target lesion with a fibrous cap thickness (FCT) < 100 μm and lipid arc > 90° as defined by optical coherence tomography (OCT) were recruited. A total of 220 patients who met the selection criteria but did not meet the exclusion criteria will be finally recruited and randomized to receive treatment with TXL (n = 110) or placebo (n = 110) for a duration of 12 months. The primary endpoint was the difference in the minimum FCT of the coronary target lesion between TXL and placebo groups at the end of the 12-month follow-up. Secondary endpoints included: (1) changes of the maximum lipid arc and length of the target plaque, and the percentage of lipid, fibrous, and calcified plaques at the end of the 12-month period; (2) the incidence of composite cardiovascular events and coronary revascularization within the 12 months; (3) changes in the grade and scores of the angina pectoris as assessed using the Canadian Cardiovascular Society (CCS) grading system and Seattle angina questionnaire (SAQ) score, respectively; and (4) changes in hs-CRP serum levels. The results of the TXL-CAP trial will provide additional clinical data for revealing whether TXL capsules stabilizes coronary vulnerable plaques in Chinese ACS patients.

OBJECTIVE: To evaluate the immediate effect of Kuanxiong Aerosol (KXA) on perioperative coronary microcirculation in patients with unstable angina (UA) suffering from elective percutaneous coronary intervention (PCI). METHODS: From February 2021 to July 2023, UA inpatients who underwent PCI alone in the left anterior descending (LAD) branch were included. Random numbers were generated to divide patients into the trial group and the control group at a ratio of 1:1. The index of coronary microcirculation resistance (IMR) was measured before PCI, and the trial group was given two sprays of KXA, while the control group was not given. IMR was measured again after PCI, cardiac troponin I (cTnI) and creatine kinase isoenzyme-MB (CK-MB) were detected before and 24 h after surgery, and major cardiovascular adverse events (MACEs) were recorded for 30 days. The data statistics and analysis personnel were blinded. RESULTS: Totally 859 patients were screened, and 62 of them were involved into this study. Finally, 1 patient in the trial group failed to complete the post-PCI IMR and was excluded, 30 patients were included for data analysis, while 31 patients in the control group were enrolled in data analysis. There was no significant difference in baseline data (age, gender, risk factors, previous history, biochemical index, and drug therapy, etc.) between the two groups. In addition, differences in IMR, cTnI and CK-MB were not statistically significant between the two groups before surgery. After PCI, the IMR level of the trial group was significantly lower than that of the control group (19.56 ± 14.37 vs. 27.15 ± 15.03, P=0.048). Besides, the incidence of perioperative myocardial injury (PMI) was lower in the trial group, but the difference was not statistically significant (6.67% vs. 16.13%, P=0.425). No MACEs were reported in either group. CONCLUSIONS KXA has the potential of improving coronary microvascular dysfunction. This study provides reference for the application of KXA in UA patients undergoing elective PCI. (Registration No. ChiCTR2300069831).
Humans ; Percutaneous Coronary Intervention ; Male ; Microcirculation/drug effects* ; Female ; Angina, Unstable/physiopathology* ; Pilot Projects ; Middle Aged ; Aged ; Drugs, Chinese Herbal/pharmacology* ; Aerosols ; Troponin I/blood* ; Coronary Circulation/drug effects* ; Elective Surgical Procedures