1.Translational Mechanisms of Circular RNAs and The Roles of Their Encoded Peptides in Tumor Initiation and Regulation
Qiong XIANG ; Li-Chang YANG ; Zan LI ; Yun LING
Progress in Biochemistry and Biophysics 2026;53(2):356-368
Circular RNAs (circRNAs) represent a distinct group of RNA molecules produced through back-splicing of precursor mRNAs. Their covalently closed structure, which lacks both a 5′ cap and a poly(A) tail, renders them highly resistant to exonucleolytic degradation and contributes to their remarkable intracellular stability. Although circRNAs were historically viewed as noncoding transcripts, accumulating evidence indicates that certain circRNAs can undergo translation under appropriate molecular contexts. Two major modes of noncanonical translation have been described so far: initiation mediated by internal ribosome entry sites (IRESs) and translation triggered by N6-methyladenosine (m6A) modification. Recent studies have revealed that, beyond their canonical classification as non-coding RNAs, circRNAs can give rise to functional peptides through cap-independent translational mechanisms. Accumulating evidence indicates that circRNA-encoded peptides participate in key biological processes during tumor initiation and progression by modulating tumor-associated signaling pathways and protein-protein interaction networks. Functionally, these peptides may promote tumor cell proliferation, migration, invasion, and epithelial-mesenchymal transition, while others exert tumor-suppressive effects by inhibiting oncogenic signaling pathways or interfering with critical protein interactions. Their dual and context-dependent functions highlight the complexity of circRNA-mediated regulation and suggest that these translation products participate in multiple layers of tumor initiation and progression. In this review, we synthesize current knowledge regarding the molecular mechanisms that enable circRNAs to be translated, with particular attention to IRES-driven initiation, m6A-dependent regulation, ribosome accessibility, and the structural determinants required for translation competence. We further summarize well-characterized circRNA-encoded peptides and discuss how they influence tumor-associated signaling networks. In addition, we examine the potential translational applications of these peptides, including their value as diagnostic indicators, prognostic markers, or therapeutic entry points. Their inherent sequence stability, relative expression specificity, and detectability in clinical specimens make circRNA-derived peptides promising candidates for future biomarker and therapeutic development. Overall, circRNA translation research is reshaping our understanding of RNA function and offers new perspectives for studying tumor biology. We propose that expanding investigations into circRNA-encoded peptides will not only improve the mechanistic resolution of cancer research but may also pave the way for innovative strategies in precision oncology, including RNA-based therapeutics and peptide-targeting interventions.
2.Translational Mechanisms of Circular RNAs and The Roles of Their Encoded Peptides in Tumor Initiation and Regulation
Qiong XIANG ; Li-Chang YANG ; Zan LI ; Yun LING
Progress in Biochemistry and Biophysics 2026;53(2):356-368
Circular RNAs (circRNAs) represent a distinct group of RNA molecules produced through back-splicing of precursor mRNAs. Their covalently closed structure, which lacks both a 5′ cap and a poly(A) tail, renders them highly resistant to exonucleolytic degradation and contributes to their remarkable intracellular stability. Although circRNAs were historically viewed as noncoding transcripts, accumulating evidence indicates that certain circRNAs can undergo translation under appropriate molecular contexts. Two major modes of noncanonical translation have been described so far: initiation mediated by internal ribosome entry sites (IRESs) and translation triggered by N6-methyladenosine (m6A) modification. Recent studies have revealed that, beyond their canonical classification as non-coding RNAs, circRNAs can give rise to functional peptides through cap-independent translational mechanisms. Accumulating evidence indicates that circRNA-encoded peptides participate in key biological processes during tumor initiation and progression by modulating tumor-associated signaling pathways and protein-protein interaction networks. Functionally, these peptides may promote tumor cell proliferation, migration, invasion, and epithelial-mesenchymal transition, while others exert tumor-suppressive effects by inhibiting oncogenic signaling pathways or interfering with critical protein interactions. Their dual and context-dependent functions highlight the complexity of circRNA-mediated regulation and suggest that these translation products participate in multiple layers of tumor initiation and progression. In this review, we synthesize current knowledge regarding the molecular mechanisms that enable circRNAs to be translated, with particular attention to IRES-driven initiation, m6A-dependent regulation, ribosome accessibility, and the structural determinants required for translation competence. We further summarize well-characterized circRNA-encoded peptides and discuss how they influence tumor-associated signaling networks. In addition, we examine the potential translational applications of these peptides, including their value as diagnostic indicators, prognostic markers, or therapeutic entry points. Their inherent sequence stability, relative expression specificity, and detectability in clinical specimens make circRNA-derived peptides promising candidates for future biomarker and therapeutic development. Overall, circRNA translation research is reshaping our understanding of RNA function and offers new perspectives for studying tumor biology. We propose that expanding investigations into circRNA-encoded peptides will not only improve the mechanistic resolution of cancer research but may also pave the way for innovative strategies in precision oncology, including RNA-based therapeutics and peptide-targeting interventions.
3.Dynamic Effects of High-Altitude Exposure on Sleep and Mood States and the Underlying Neural Mechanisms
Wanlin HE ; Hailong LI ; Jinli MENG ; Li FENG ; Zan ZHOU ; Yonghong HUANG ; Kejin XIANG ; Hengyan LI ; Xiaomei LI ; Yuanyuan HE ; Xiaoyan LUO ; Lu CHE ; Xiaoqi HUANG
Journal of Sichuan University (Medical Sciences) 2025;56(5):1313-1319
Objective To analyze changes in sleep,mood state,and brain function in healthy populations living in near-sea-level environments before and after exposure to high-altitude environment,and to explore the correlations between regional brain functional changes and variations in sleep and mood states.Methods A total of 45 healthy volunteers were enrolled.The participants came from regions of near-sea-level altitudes and were exposed to the high-altitude environment for a short period of time.The Pittsburgh Sleep Quality Index(PSQI),Zung Self-Rating Depression Scale(SDS),Patient Health Questionnaire-9(PHQ-9),Zung Self-Rating Anxiety Scale(SAS),and Generalized Anxiety Disorder-7(GAD-7)were administered to assess sleep quality as well as depressive and anxiety symptoms at 4 time points—prior to high-altitude exposure,immediately after exposure,one month after returning to low-altitude regions,and three months after returning to low-altitude regions.Resting-state functional magnetic resonance imaging(rs-fMRI)data were collected before and after high-altitude exposure,and regional brain functional parameters,including the amplitude of low-frequency fluctuations(ALFF)and functional connectivity strength,were analyzed.Statistical analyses were performed,including a linear mixed-effects model to evaluate longitudinal changes in scale scores,paired-sample t-tests to compare brain function differences before and after exposure,and Pearson correlation analyses to examine the relationship between brain functional changes and alterations in sleep and mood states.Results Compared with the pre-exposure findings,the participants exhibited significantly increased PSQI scores(8.89±4.41 vs.5.08±2.69,P<0.05)and PHQ-9 scores(3.60±4.19 vs.1.54±2.30,P<0.05)immediately after high-altitude exposure.One month after returning to the low-altitude environment,both sleep and depression scores decreased relative to the findings immediately after exposure(PSQI:3.88±2.13 vs.8.89±4.41,P<0.05;PHQ-9:1.50±2.25 vs.3.60±4.19,P<0.05)and showed no statistically significant difference compared with the pre-exposure findings(P>0.05).Three months after returning to near-sea-level environment,sleep,depression,and anxiety scores were all reduced compared with the findings immediately after exposure(PSQI:3.76±2.31 vs.8.89±4.41,P<0.05;PHQ-9:1.24±2.13 vs.3.60±4.19,P<0.05;SAS:23.84±5.93 vs.27.93±7.05,P<0.05),also showing no significant difference compared with the pre-exposure levels(P>0.05).Brain function analysis revealed that,relative to the pre-exposure levels,ALFF in the bilateral superior temporal gyrus,insula,and dorsolateral prefrontal cortex(DLPFC)increased after high-altitude exposure(P<0.05),and that functional connectivity strength in the DLPFC was also elevated(P<0.05).Furthermore,changes in DLPFC functional connectivity strength were positively correlated with changes in sleep and mood scores(P<0.05).Conclusion High-altitude exposure has a significant impact on the sleep,mood states,and brain function of populations from near-sea-level regions,and DLPFC,in particular,is closely associated with changes in sleep and mood states.The findings of this study provide a theoretical basis for health management and intervention strategies in high-altitude environments.
4.Donor-driven advancements in reconstructive surgery: 20 years of facial transplantation reconstruction
Yixuan ZHAO ; Tao ZAN ; Qingfeng LI
Chinese Journal of Plastic Surgery 2025;41(5):441-446
'Injury but not disability, disability but not useless’ is the guiding principle behind the establishment of plastic and reconstructive surgery, making it a unique specialty in modern medicine. Its development relies not only on the optimized use of donor resources but also on technological advancements and innovations in concepts. However, in the face of severe tissue damage caused by burns, trauma, and congenital deformities, traditional repair method often fall short, necessitating more effective solutions. Against this backdrop, progress in donor sourcing and interdisciplinary innovation will inject new vitality into reconstructive surgery. In this context, we take facial transplantation reconstruction as a starting point, reviewing and organizing the technological development, issues, and challenges of autologous and allogeneic facial transplantation reconstruction from the perspective of donors. This exploration aims to shed light on the future direction of this field and gain a deeper understanding of the present and future of donor-driven reconstructive surgery.
5.Contralateral posteromedial thigh flap for salvage breast reconstruction with adductor magnus perforator flap failure
Dajiang SONG ; Tianyi ZHANG ; Zan LI ; Yixin ZHANG
Chinese Journal of Plastic Surgery 2025;41(6):577-582
Objective:To summarize the technical experience of using a contralateral free gracilis myocutaneous flap combined with an adductor magnus perforator flap for salvaging failure of breast reconstruction after transplantation with the free adductor magnus perforator flap.Methods:A retrospective analysis was conducted on patients with breast cancer who received contralateral posteromedial thigh flap (gracilis myocutaneous flap combined with adductor magnus perforator flap) transplantation for immediate unilateral breast reconstruction developed vascular crisis and caused flap necrosis at the Department of Oncology Plastic Surgery, Hunan Cancer Hospital, between December 2016 to December 2022. All patients with early-stage breast cancer received modified radical mastectomy. All patients were selected to undergo the immediate breast reconstruction surgery with unilateral free adductor magnus perforator flap transplantation. The proximal end of internal mammary vessels were used as the recipient vessels in all cases. After the emergency exploration confirmed the necrosis of the flap, a contralateral free gracilis myocutaneous flap combined with adductor magnus perforator flap were immediately harvested for salvage breast reconstruction. The vascular pedicle of the gracilis muscular branch and the adductor magnus perforator branch were anastomosed with the proximal and distal ends of the internal mammary vessels, respectively. Postoperative patient monitoring was conducted intensively, with follow-up assessments focusing on breast contour and donor site recovery.Results:A total of 5 patients were included, aged 26 to 42 years, with an average of (31.5±1.8) years. All salvaged breast reconstruction surgeries were successful, the salvaged flap measured 15.0 cm×6.0 cm×4.0 cm-17.0 cm×7.5 cm×5.5 cm. All the transplanted flaps survived after the operation, with satisfactory breast contour, good flap elasticity, and no contracture or deformation. The donor sites of both thigh flaps healed well, leaving only linear scars and no significant functional impairment to the lower limbs. Follow-up ranged from 9 to 24 months, with an average of 15.7 months. The breast shape was satisfactory, and there was no recurrence of breast cancer.Conclusion:The donor site morbidity of the posteromedial thigh flap is relatively small. When unilateral flap transplantation fails, immediate transfer of the contralateral flap can be chosen for salvage reconstruction. This approach ensures symmetrical donor site outcomes and is generally well-accepted by patients.
6.The strategy and pitfalls of bilateral free posteromedial thigh flap transplantation for bilateral breast reconstruction
Dajiang SONG ; Peixian CHEN ; Zan LI ; Yixin ZHANG
Chinese Journal of Plastic Surgery 2025;41(9):931-938
Objective:To explore the technical points and precautions of using bilateral free posteromedial thigh flap to reconstruct bilateral breasts.Methods:A retrospective analysis was conducted on the clinical data of patients who underwent bilateral mastectomy and bilateral free posteromedial thigh flap transplantation for bilateral breast reconstruction at Hunan Cancer Hospital from June 2020 to January 2023. The operation was carried out simultaneously by two groups of doctors. Breast surgeons performed modified radical mastectomy for breast cancer or subcutaneous mastectomy. The flap group prepared bilateral free posteromedial thigh flaps. The posteromedial thigh flaps were designed in three patterns: transverse, vertical and oblique. The intrathoracal vessels were used as recipient vessels in all cases. There were two types of vascular anastomosis method: ① For flaps with single vascular pedicle, the artery was anastomosed with the proximal end of the internal thoracic artery, and the only accompanying vein was anastomosed with the proximal end of the internal thoracic vein, or the two accompanying veins were anastomosed with the proximal and distal ends of the internal thoracic vein; ② For flaps with dual vascular pedicles, arteries were anastomosed with the proximal and distal ends of the internal thoracic artery, and the accompanying veins on both sides communicated with the proximal and distal ends of the internal thoracic vein, respectively. Normal distribution measurement data were expressed as Mean±SD.Results:A total of 9 female patients were enrolled, aged 29 to 43 years, with an average age of 38.3 years. Among them, bilateral breast cancer was considered in 4 cases, unilateral breast cancer with multiple nodules in the opposite breast was in 3 cases, and bilateral multiple nodules along with high-risk of developing breast cancer suggested by gene testing were found in 2 cases. Modified radical mastectomy for breast cancer and nipple-sparing subcutaneous mastectomy were performed in 7 and 11 breasts, respectively. There were three design method for the posteromedial thigh flap: horizontal design (6 thighs); vertical design (6 thighs); diagonal design (6 thighs). A total of 18 posteromedial thigh flaps were raised. Four different types of posteromedial thigh flaps were used: gracilis muscle flap (6 thighs); great adductor muscle perforator flap (5 thighs); great adductor muscle flap (5 thighs); femoral gracilis flap+ adductor magnus flap (2 thighs). The skin flaps harvested were (18.9±0.6) cm in length, (7.2±0.4) cm in width and (4.2±0.3) cm in thickness. The average weight of the skin flaps were 235 grams (185-355 grams). The aforementioned vascular anastomosis method ① and ② were carried out in 15 and 3 breasts, respectively. The patients were followed up for 6 to 32 months, with an average of 17.3 months. All skin flaps survived, and the reconstructed breasts presented with good appearance, good elasticity, and no skin flap contraction or deformation occurred; scarring on the donor area was linear and mild; there was no significant impact on lower limb movement. The breast shape was satisfactory, and there was no recurrence of breast cancer.Conclusion:The application of bilateral free posteromedial thigh flap transplantation for reconstruction of bilateral breasts has flexible flap preparation and vascular anastomosis forms, which can achieve satisfactory result of bilateral symmetry.
7.Effect of integrin α5 on NLRP3 expression in periodontal ligament fibroblasts within an inflammatory microenvironment
DAI Jingyi ; CAI Hongxuan ; SI Weixing ; ZHANG Zan ; WANG Zhurui ; LI Mengsen ; TIAN Ya guang
Journal of Prevention and Treatment for Stomatological Diseases 2025;33(1):24-32
Objective:
To investigate the effect of integrin α5 on the expression of NOD-like receptor thermal protein domain associated protein 3 (NLRP3) in periodontal ligament fibroblasts (PDLFs) within an inflammatory microenvironment.
Methods:
This study was approved by the Ethics Committee of Laboratory animals. After rat PDLFs were treated with LPS (0.5, 5, and 50 µg/mL) for 24 h, the primary medium was discarded and replaced with serum-free culture medium. After 24 h, the supernatant was collected and mixed with DMEM medium containing 10% exosome-free serum at a volume ratio of 1:1 to obtain conditioned medium (CM). The groups were labeled as the 0.5-CM, 5-CM, and 50-CM groups. In addition, PDLFs cultured in DMEM medium containing 10% exosome-free serum were considered the 0-CM group. PDLFs were cultured with the above CM. In the inhibitor group, PDLFs were cultured in 0-CM containing different concentrations of integrin α5 inhibitor ATN-161 (0, 0.025, 0.25, 2.5, 25, and 250 μg/mL). The effect of CM and integrin α5 inhibitor ATN-161 on cell viability was assessed using the CCK-8 assay. According to the CCK-8 results, in further inhibitor intervention experiments, PDLFs were cultured in 0-CM, 5-CM (without/with 25 μg/mL ATN-161), and 0-CM containing 25 μg/mL ATN-161, which were labeled as the 0-CM, 5-CM, ATN-161+5-CM, and ATN-161 groups, respectively. The expression changes of integrin α5 and NLRP3 were detected using Western blot and qRT-PCR techniques. For in vivo experiments, 24 rats were randomly divided into four groups (n=6). The control group contained healthy rats that received no treatment. The rats in the other three groups were injected with 40 µL of 0-CM containing 25 μg/mL ATN-161 or 5-CM (without or with 25 μg/mL ATN-161) on the palatal side of the left maxillary first molar every three days; these groups were classified as the ATN-161, 5-CM, and ATN-161+5-CM groups, respectively. On the 30th day, the left maxillary tissue of rats was used for Micro-CT, HE staining, and immunohistochemical detection.
Results :
The CCK-8 assay showed that CM, 25 μg/mL ATN-161, and ATN-161 concentrations below 25 μg/mL had no significant effect on cell viability at 12 h and 24 h (P > 0.05). 50-CM and 25 μg/mL ATN-161 significantly inhibited cell viability at 48 h (P < 0.05). For in vitro experiments, compared to the 0-CM group, both the protein and mRNA levels of integrin α5 and NLRP3 were significantly increased in rat PDLFs in the 5-CM group (P < 0.05). Intervention with 25 μg/mL ATN-161 significantly attenuated the enhancement of 5-CM on the expression of integrin α5 and NLRP3 (P < 0.05). For in vivo experiments, compared to the control group, alveolar bone resorption and periodontal inflammatory cell infiltration were significantly increased in the 5-CM and ATN-161+5-CM groups, and the expression of integrin α5 and NLRP3 was significantly increased (P < 0.01). However, compared to the 5-CM group, the ATN-161+5-CM group had less alveolar bone resorption and fewer periodontal inflammatory cells. Further, the expression of integrin α5 and NLRP3 was significantly reduced (P < 0.01).
Conclusion
In vitro and in vivo experiments showed that integrin α5 mediated NLRP3 expression in PDLFs under an inflammatory microenvironment. ATN-161 inhibited the expression of integrin α5, thus significantly downregulating the expression of NLRP3, which plays a role in inhibiting inflammation.
8.Effect of pravastatin on functional recovery from sciatic nerve crush injury in rats
Zan LIU ; Ran AN ; Baocheng LI
Chinese Journal of Tissue Engineering Research 2025;29(5):942-950
BACKGROUND:Pravastatin is a clinically effective drug for the treatment of hypercholesterolemia and is now found to play a beneficial role in the treatment of CNS injury;however,the mechanism remains unknown. OBJECTIVE:To ascertain the possible mechanism of action and whether pravastatin medication can expedite functional recovery following sciatic nerve crush injury. METHODS:Male Sprague-Dawley rats were randomly assigned into:pravastatin(sciatic nerve crush injury+pravastatin gavage),negative control(sciatic nerve crush injury+saline gavage),and sham operation(sciatic nerve exposure but no injury+saline gavage).While the other two groups received comparable amounts of saline gavage,the pravastatin group received postoperative pravastatin(5 mg/kg)by gavage for 1 week.The general conditions of the rats in each group were observed after operation.Sciatic function index was evaluated at the end of the 2nd,4th,6th,and 8th week after operation,and the wet mass ratio of the gastrocnemius muscle was measured at the end of the 8th week after operation.The levels of inflammatory cytokines in serum were measured using ELISA.Histomorphometrics was used to measure the number of myelinated nerve fibers,fiber diameter,axon diameter,and myelin sheath thickness.RT-qPCR assay was used to measure the relative mRNA expression of nerve growth factor and brain-derived neurotrophic factor,and western blot was used to measure the protein expression of growth-associated protein 43. RESULTS AND CONCLUSION:Compared with the negative control group,the sciatic function index in the pravastatin group recovered faster(P<0.05)and was closer to the level of the sham operation group,the expression of tumor necrosis factor α and interleukin 6 in serum was lower(P<0.05)and close to that of the sham operation group,and the relative mRNA expression of nerve growth factor and brain-derived neurotrophic factor in the sciatic nerve increased(P<0.05 or P<0.01),the relative protein expression of growth-associated protein 43 in the sciatic nerve was also significantly increased(P<0.05),the number of myelinated nerve fibers was increased more,and the values of fiber diameter,axon diameter,and myelin sheath thickness were larger(P<0.01)and closer to those of the sham operation group.To conclude,treatment with pravastatin accelerates functional recovery from sciatic nerve crush injury by a possible mechanism of inhibiting the expression of tumor necrosis factor α and interleukin 6 and promoting the secretion of neurotrophic factors nerve growth factor and brain-derived neurotrophic factor.
9.Effect of Acupuncture Combined with Bloodletting and Cupping on the Expression of Coagulation-Complement-Mast Cell Activation Axis-Related Factors in Patients with Chronic Spontaneous Urticaria:Randomize-controlled Study
Yuzhu DU ; Yuqiang XUE ; Xiang LIU ; Yu SHI ; Hongkun LI ; Wenshan LIU ; Zan TIAN ; Yutong HU ; Yanjun WANG
Journal of Traditional Chinese Medicine 2025;66(2):150-156
ObjectiveTo observe the clinical efficacy of acupuncture combined with bloodletting and cupping in the treatment of chronic spontaneous urticaria(CSU) and to explore its potential mechanisms of action. MethodsSeventy CSU patients were randomly divided into loratadine group and acupuncture + bloodletting group, with 35 patients in each group. The loratadine group received oral loratadine tablets, 10 mg once daily in the evening. The acupuncture + bloodletting group received acupuncture at Zhongwan (CV 12), Guanyuan (CV 4), Tianshu (ST 25), Zusanli (ST 36), Sanyinjiao (SP 6), Xuehai (SP 10), Quchi (LI 11), Hegu (LI 4), Taichong (LR 3), Baihui (GV 20), and Shenting (GV 24), once daily,along with bloodletting and cupping at Dazhui (GV 14) and Geshu (BL 17), every other day. Both groups were treated for 4 weeks. The 7-day urticaria activity score(UAS7) was assessed before and after the treatment, and levels of serum immunoglobulin E (IgE), interleukin-4 (IL-4), interleukin-5 (IL-5), eosinophil cationic protein (ECP), plasma tissue factor (TF), activated factor Ⅶ (FⅦa), prothrombin fragment 1+2 (F1+2), D-dimer (D-D) and complement component 5a (C5a) were detected. ResultsA total of 65 patients were included in the final analysis, 32 in the loratadine group and 33 in the acupuncture + bloodletting group. Before treatment, there was no significant difference in UAS7 score, serum IgE, IL-4, IL-5, ECP levels, or plasma TF, FⅦa, F1+2, D-D, C5a levels between groups (P> 0.05). After treatment, both groups showed significant reductions in UAS7 score, serum IgE, IL-4, IL-5, and plasma TF, FⅦa, F1+2, D-D, and C5a levels compared to those before treatment (P<0.01). However, after treatment, there was no significant difference in UAS7 score and serum ECP, IgE, IL-4, IL-5 levels between groups (P>0.05). The acupuncture + bloodletting group showed lower plasma TF, FⅦa, F1+2, D-D and C5a levels compared to the loratadine group (P<0.05 or P<0.01). ConclusionAcupuncture combined with bloodletting and cupping can effectively improve the skin symptoms of CSU patients and reduce the levels of inflammatory factors. The potential mechanism of action may involve the regulation of the coagulation-complement-mast cell activation axis, thereby inhibiting mast cell degranulation.
10.Exploration and practice of local internationalization and enhanced virtual blended learning model in the context of new medical education
Zan WANG ; Mingjing SHANG ; Min LI ; Dan ZHU ; Shixiong DENG
Chinese Journal of Medical Education Research 2025;24(5):599-603
Since 2020, with the Sino-foreign cooperative education of clinical medicine as the pilot project, Chongqing Medical University (CQMU) has integrated its high-quality resources with those from University of Leicester (UoL) and explored the practice of enhanced virtual blended learning model from the aspects of self-learning before class, practical application during class, and consolidation and improvement after class. In addition, the implementation of this model was ensured from the aspects of teacher-student communication, platform construction, and optimization of evaluation mechanism, so as to replace the traditional teaching model and promote the implementation of local internationalization strategy. At present, preliminary results of student training have been achieved, and the project has passed the clinical medicine professional certification of the Ministry of Education and CQMU-UoL interim review.


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