ObjectiveMitochondria are not only the central organelles responsible for cellular energy metabolism but also play essential roles in regulating cell cycle progression and cytoskeletal dynamics. In recent years, accumulating evidence has demonstrated that mitochondrial homeostasis is closely associated with mitotic progression and cytokinesis. Schizosaccharomyces pombe serves as a classical and well-established model organism. Because its cell cycle regulatory mechanisms are highly conserved throughout evolution, its genetic background is clearly defined, and experimental manipulation is efficient and convenient, it has been extensively applied in studies of cell growth, division, and reproductive mechanisms. The SPBC1604.04 gene encodes a previously uncharacterized mitochondrial carrier protein in Schizosaccharomyces pombe. This gene is located on chromosome II and spans 1 018 base pairs in length. It encodes a protein consisting of 238 amino acids with a predicted molecular mass of approximately 31.03 ku. Bioinformatic analysis predicts that this protein is responsible for the transport of thiamine pyrophosphate (TPP) into mitochondria. However, the effects of SPBC1604.04 gene deletion on mitotic cell dynamics under different temperature conditions have not been fully elucidated. MethodsThe SPBC1604.04 deletion strain of Schizosaccharomyces pombe was used as the experimental model. Fluorescent protein markers were constructed in the deletion background to label mitochondria, microtubules, actin, myosin, the nuclear envelope, and chromosomes. Live-cell imaging was performed using a TCS-SP8 laser scanning confocal microscope under normal temperature conditions (25℃) and heat stress conditions (37℃). Time-lapse microscopy was applied to dynamically monitor mitochondrial morphology and distribution, spindle assembly and elongation, chromosome segregation, as well as the formation and constriction of the actomyosin ring during cytokinesis. ImageJ software was used for quantitative measurements, including microtubule length during mitosis, spindle length at different mitotic stages, mitochondrial fluorescence intensity as an indicator of mitochondrial content, actomyosin ring length, nuclear envelope area, and chromosome segregation timing. Statistical analyses were conducted to compare phenotypic differences between the wild-type and SPBC1604.04 deletion strains at both temperature conditions. Through these analyses, we systematically investigated the impact of SPBC1604.04 deletion on mitotic cell dynamics in fission yeast under both normal physiological conditions and temperature stress. ResultsAt 25℃, compared with wild-type cells, the SPBC1604.04Δ strain exhibited a pronounced tendency toward mitochondrial fragmentation, accompanied by abnormal mitochondrial content and a significant reduction in mitochondrial fluorescence intensity. These observations suggest impaired mitochondrial homeostasis under normal growth conditions. In addition, the constriction time of actomyosin ring during cytokinesis was markedly prolonged, indicating that deletion of SPBC1604.04 affects the dynamics of the contractile machinery. However, no obvious defects were observed in spindle assembly, spindle elongation, or chromosome segregation. Under heat stress at 37℃, mitochondrial morphology in the SPBC1604.04Δ strain showed a tendency to recover toward a continuous tubular network structure. Mitochondrial content was restored, fluorescence intensity increased, and the constriction time of the actomyosin ring returned to levels comparable to those of wild-type cells. These results indicate that the mitotic defects observed at normal temperature are partially or fully alleviated under heat stress conditions. ConclusionThis study demonstrates that deletion of the SPBC1604.04 gene leads to abnormal mitochondrial content in Schizosaccharomyces pombe. The mitochondrial carrier protein SPBC1604.04 participates in regulating actomyosin ring constriction during mitosis but does not appear to be directly involved in the regulation of spindle dynamics or chromosome segregation. Our findings provide key experimental evidence for understanding the functional link between the SPBC1604.04 gene, mitochondrial homeostasis, and mitotic regulation.

ObjectiveMitochondria are not only the central organelles responsible for cellular energy metabolism but also play essential roles in regulating cell cycle progression and cytoskeletal dynamics. In recent years, accumulating evidence has demonstrated that mitochondrial homeostasis is closely associated with mitotic progression and cytokinesis. Schizosaccharomyces pombe serves as a classical and well-established model organism. Because its cell cycle regulatory mechanisms are highly conserved throughout evolution, its genetic background is clearly defined, and experimental manipulation is efficient and convenient, it has been extensively applied in studies of cell growth, division, and reproductive mechanisms. The SPBC1604.04 gene encodes a previously uncharacterized mitochondrial carrier protein in Schizosaccharomyces pombe. This gene is located on chromosome II and spans 1 018 base pairs in length. It encodes a protein consisting of 238 amino acids with a predicted molecular mass of approximately 31.03 ku. Bioinformatic analysis predicts that this protein is responsible for the transport of thiamine pyrophosphate (TPP) into mitochondria. However, the effects of SPBC1604.04 gene deletion on mitotic cell dynamics under different temperature conditions have not been fully elucidated. MethodsThe SPBC1604.04 deletion strain of Schizosaccharomyces pombe was used as the experimental model. Fluorescent protein markers were constructed in the deletion background to label mitochondria, microtubules, actin, myosin, the nuclear envelope, and chromosomes. Live-cell imaging was performed using a TCS-SP8 laser scanning confocal microscope under normal temperature conditions (25℃) and heat stress conditions (37℃). Time-lapse microscopy was applied to dynamically monitor mitochondrial morphology and distribution, spindle assembly and elongation, chromosome segregation, as well as the formation and constriction of the actomyosin ring during cytokinesis. ImageJ software was used for quantitative measurements, including microtubule length during mitosis, spindle length at different mitotic stages, mitochondrial fluorescence intensity as an indicator of mitochondrial content, actomyosin ring length, nuclear envelope area, and chromosome segregation timing. Statistical analyses were conducted to compare phenotypic differences between the wild-type and SPBC1604.04 deletion strains at both temperature conditions. Through these analyses, we systematically investigated the impact of SPBC1604.04 deletion on mitotic cell dynamics in fission yeast under both normal physiological conditions and temperature stress. ResultsAt 25℃, compared with wild-type cells, the SPBC1604.04Δ strain exhibited a pronounced tendency toward mitochondrial fragmentation, accompanied by abnormal mitochondrial content and a significant reduction in mitochondrial fluorescence intensity. These observations suggest impaired mitochondrial homeostasis under normal growth conditions. In addition, the constriction time of actomyosin ring during cytokinesis was markedly prolonged, indicating that deletion of SPBC1604.04 affects the dynamics of the contractile machinery. However, no obvious defects were observed in spindle assembly, spindle elongation, or chromosome segregation. Under heat stress at 37℃, mitochondrial morphology in the SPBC1604.04Δ strain showed a tendency to recover toward a continuous tubular network structure. Mitochondrial content was restored, fluorescence intensity increased, and the constriction time of the actomyosin ring returned to levels comparable to those of wild-type cells. These results indicate that the mitotic defects observed at normal temperature are partially or fully alleviated under heat stress conditions. ConclusionThis study demonstrates that deletion of the SPBC1604.04 gene leads to abnormal mitochondrial content in Schizosaccharomyces pombe. The mitochondrial carrier protein SPBC1604.04 participates in regulating actomyosin ring constriction during mitosis but does not appear to be directly involved in the regulation of spindle dynamics or chromosome segregation. Our findings provide key experimental evidence for understanding the functional link between the SPBC1604.04 gene, mitochondrial homeostasis, and mitotic regulation.

OBJECTIVE: To evaluate the dynamic changes of glucocorticoid (GC) dose and the feasibility of GC discontinuation in rheumatoid arthritis (RA) patients under the background of Chinese medicine (CM). METHODS: This multicenter retrospective cohort study included 1,196 RA patients enrolled in the China Rheumatoid Arthritis Registry of Patients with Chinese Medicine (CERTAIN) from September 1, 2019 to December 4, 2023, who initiated GC therapy. Participants were divided into the Western medicine (WM) and integrative medicine (IM, combination of CM and WM) groups based on medication regimen. Follow-up was performed at least every 3 months to assess dynamic changes in GC dose. Changes in GC dose were analyzed by generalized estimator equation, the probability of GC discontinuation was assessed using Kaplan-Meier curve, and predictors of GC discontinuation were analyzed by Cox regression. Patients with <12 months of follow-up were excluded for the sensitivity analysis. RESULTS: Among 1,196 patients (85.4% female; median age 56.4 years), 880 (73.6%) received IM. Over a median 12-month follow-up, 34.3% (410 cases) discontinued GC, with significantly higher rates in the IM group (40.8% vs. 16.1% in WM; P<0.05). GC dose declined progressively, with IM patients demonstrating faster reductions (median 3.75 mg vs. 5.00 mg in WM at 12 months; P<0.05). Multivariate Cox analysis identified age <60 years [P<0.001, hazard ratios (HR)=2.142, 95% confidence interval (CI): 1.523-3.012], IM therapy (P=0.001, HR=2.175, 95% CI: 1.369-3.456), baseline GC dose ⩽7.5 mg (P=0.003, HR=1.637, 95% CI: 1.177-2.275), and absence of non-steroidal anti-inflammatory drugs use (P=0.001, HR=2.546, 95% CI: 1.432-4.527) as significant predictors of GC discontinuation. Sensitivity analysis (545 cases) confirmed these findings. CONCLUSIONS RA patients receiving CM face difficulties in following guideline-recommended GC discontinuation protocols. IM can promote GC discontinuation and is a promising strategy to reduce GC dependency in RA management. (Trial registration: ClinicalTrials.gov, No. NCT05219214).
Adult ; Aged ; Female ; Humans ; Male ; Middle Aged ; Arthritis, Rheumatoid/drug therapy* ; Glucocorticoids/therapeutic use* ; Medicine, Chinese Traditional ; Retrospective Studies

Osteoarthritis (OA), the most prevalent joint disease of late life, is closely linked to cellular senescence. Previously, we found that the senescence of fibroblast-like synoviocytes (FLS) played an essential role in the degradation of cartilage. In this work, single-cell sequencing data further demonstrated that cartilage acidic protein 1 (CRTAC1) is a critical secreted factor of senescent FLS, which suppresses mitophagy and induces mitochondrial dysfunction by regulating SIRT3 expression. In vivo, deletion of SIRT3 in chondrocytes accelerated cartilage degradation and aggravated the progression of OA. Oppositely, intra-articular injection of adeno-associated virus expressing SIRT3 effectively alleviated OA progression in mice. Mechanistically, we demonstrated that elevated CRTAC1 could bind with NRF2 in chondrocytes, which subsequently suppresses the transcription of SIRT3 in vitro. In addition, SIRT3 reduction could promote the acetylation of FOXO3a and result in mitochondrial dysfunction, which finally contributes to the degradation of chondrocytes. To conclude, this work revealed the critical role and underlying mechanism of senescent FLSs-derived CRTAC1 in OA progression, which provided a potential strategy for the OA therapy.

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.

Objective:This study aims to investigate the expression of uridine diphosphate-glucose[]pyrophos-phorylase 2(UGP2)in breast cancer(BC)tissues and its oncogenic mechanism,assessing its potential value as a diag-nostic and prognostic biomarker for breast cancer.Methods:(1)Online database analysis was conducted to assess UGP2 mRNA and protein expression levels in breast cancer and explore their correlation with clinical characteristics.Im-munohistochemistry(IHC)was used to verify UGP2 expression in human breast cancer tumor tissues and evaluate its relationship with clinicopathological features.(2)Kaplan-Meier survival analysis and COX regression models were used to analyze the impact of UGP2 expression on breast cancer patient prognosis.(3)Bioinformatics methods were em-ployed to investigate the correlation between UGP2 and tumor immune cell infiltration,and to predict the biological func-tions and associated signaling pathways of UGP2 in breast cancer.Results:(1)The mRNA and protein expression levels of UGP2 were upregulated in breast cancer tissues(both P<0.05),and were negatively correlated with ER-positive and PR-positive status(OR<1,P<0.05),while positively correlated with Ki-67 levels and the triple-negative breast cancer(TNBC)subtype(OR>1,P<0.05).(2)Elevated expression levels of UGP2 were associated with poorer survival rates in breast cancer patients(both P<0.05)and were identified as an independent adverse prognostic factor for breast cancer(HR=1.40,P<0.05).(3)Functional analysis results suggested that UGP2 may promote tumor progression by regulating metabolism,hormone signaling,and the immune microenvironment.Additionally,UGP2 expression was negatively cor-related with NK cell activation status and positively correlated with the inhibitory state.Conclusion:UGP2 expression is elevated in breast cancer tissues and is closely associated with poor patient prognosis.It may promote cancer pro-gression through mechanisms such as metabolic reprogramming and immune suppression.UGP2 shows promise as a potential biomarker and therapeutic target in breast cancer,providing a basis for personalized treatment.

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.

Objective:This study aims to investigate the expression of uridine diphosphate-glucose[]pyrophos-phorylase 2(UGP2)in breast cancer(BC)tissues and its oncogenic mechanism,assessing its potential value as a diag-nostic and prognostic biomarker for breast cancer.Methods:(1)Online database analysis was conducted to assess UGP2 mRNA and protein expression levels in breast cancer and explore their correlation with clinical characteristics.Im-munohistochemistry(IHC)was used to verify UGP2 expression in human breast cancer tumor tissues and evaluate its relationship with clinicopathological features.(2)Kaplan-Meier survival analysis and COX regression models were used to analyze the impact of UGP2 expression on breast cancer patient prognosis.(3)Bioinformatics methods were em-ployed to investigate the correlation between UGP2 and tumor immune cell infiltration,and to predict the biological func-tions and associated signaling pathways of UGP2 in breast cancer.Results:(1)The mRNA and protein expression levels of UGP2 were upregulated in breast cancer tissues(both P<0.05),and were negatively correlated with ER-positive and PR-positive status(OR<1,P<0.05),while positively correlated with Ki-67 levels and the triple-negative breast cancer(TNBC)subtype(OR>1,P<0.05).(2)Elevated expression levels of UGP2 were associated with poorer survival rates in breast cancer patients(both P<0.05)and were identified as an independent adverse prognostic factor for breast cancer(HR=1.40,P<0.05).(3)Functional analysis results suggested that UGP2 may promote tumor progression by regulating metabolism,hormone signaling,and the immune microenvironment.Additionally,UGP2 expression was negatively cor-related with NK cell activation status and positively correlated with the inhibitory state.Conclusion:UGP2 expression is elevated in breast cancer tissues and is closely associated with poor patient prognosis.It may promote cancer pro-gression through mechanisms such as metabolic reprogramming and immune suppression.UGP2 shows promise as a potential biomarker and therapeutic target in breast cancer,providing a basis for personalized treatment.

Objective To explore the long-term efficacy of percutaneous pulmonary valve implantation(PPVI)and the durability of the domestic self-expanding Venus P valve.Methods A total of 8 patients with post-surgical right ventricular outflow tract(RVOT)dysfunction,who were admitted to hospital from October 2014 to July 2016 and deemed anatomically suitable for PPVI with self-expanding valve,were included prospectively.Clinical,imaging,procedural and follow-up data were analyzed.The survival rates,perioperative and long-term complication rates,long-term efficacy of PPVI,and long-term function of Venus P in 8 patients were evaluated.The immediate procedural results were evaluated by clinical implant success rate,which is defined as successful valve implantation with echocardiography-assessed pulmonary regurgitation＜moderate and peak trans-pulmonary pressure gradient＜40 mmHg.Results A total of 8 patients were included,with 7 females,aged 14 to 36 years.The initial diagnosis included post-surgical Tetralogy of Fallot(5 cases),post-surgical Trilogy of Fallot(1 case),post-surgical Quadricuspid pulmonary valve stenosis(1 case)and post-surgical Double-Outlet Right Ventricle(1 case).The indications of PPVI included RVOT-pulmonary obstruction and regurgitation(1 case)and isolated regurgitation(7 cases).Clinical implant success was achieved in all of the 8 patients with firmly fixed valve,and there were no such complications as valve detachment,displacement or stent fracture.All patients experienced significant symptom relief after the procedure.The right ventricular end-diastolic volume index(RVEDVi)measured by CMR 6 months after PPVI showed a significant decrease compared to preprocedural values[(89.99±13.85)ml/m2 vs.(144.93±11.28)ml/m2,P=0.001].Postoperative pulmonary regurgitation were significantly improved or disappeared in all patients,and there was no statistically significant difference in the average peak pressure gradient measured by echocardiogram between preoperative and the latest follow-up[(23.25±8.39)mmHg vs.(18.75±6.28)mmHg,P=0.210].Over an average follow-up period of(9.25±0.71)years,1 case of infective endocarditis occurred 5 years after PPVI.During the follow-up,no death,deterioration of heart failure,malignant arrhythmia or other serious complications were observed.All patients completed 8-year follow-up,and 3 completed 10-year follow-up.All patients were graded as NYHA functional class one at the latest follow-up.Conclusions PPVI using the domestically produced self-expanding Venus P is safe and feasible for the treatment of patients with post-surgical RVOT dysfunction and suitable anatomy.Our study confirms the long-term efficacy and durability of Venus P from multiple perspectives,and no severe stent fracture occurred without pre-stent implantation in the native RVOT.

Acetabular fracture is a kind of intra-articular fracture with complicated anatomy and difficult treatment. The core of treatment lies in anatomic reduction and strong fixation. The low incidence and intricate anatomical structure present significant challenges for treatment of acetabular fractures. In recent years, significant progress has been made in the treatment of acetabular fractures, particularly in surgical approaches, robotic-assisted technology, the application of tranexamic acid, and treatment strategies for elderly patients, providing new therapeutic options. This article reviews the latest progress in acetabular fracture treatment research.