BACKGROUND:Bone marrow mesenchymal stem cells play a crucial role in treatment of diseases,such as femoral head necrosis,and the therapeutic efficacy is closely related to the quality of the cells.The empowerment of cells has become a research focus.OBJECTIVE:To investigate the effects of hypoxia mimetic dimethylglyoxal glycine pretreatment on mitophagy and differentiation capacity of human bone marrow mesenchymal stem cells.METHODS:Bone marrow mesenchymal stem cells were extracted from the bone marrow of patients' iliac crest and cultured in vitro to the third passage.The cells were treated with dimethylglyoxal glycine at 0,10,50,and 100 μmol/Lfor 24 hours,followed by the replacement with an osteogenic induction differentiation medium,which constituted the pretreatment group.The continuous treatment group was cultured directly in osteogenic induction medium containing 0,10,50,and 100 μmol/L dimethylglyoxal glycine after cell adhesion.After 7 days of induction,alkaline phosphatase staining was performed to select the most favorable conditions for osteogenic differentiation for subsequent experiments,with normally cultured bone marrow mesenchymal stem cells serving as the control group.Alkaline phosphatase staining,alkaline phosphatase activity,oil red O staining,and related RT-qPCR were used to evaluate the osteogenic and adipogenic differentiation differences of bone marrow mesenchymal stem cells between the two groups.MitoSox staining was used to detect mitochondrial reactive oxygen species levels.Mito-tracker and Lyso-tracker staining were used to detect the co-localization of mitochondria and lysosomes.The fluorescent probe JC-1 was used to measure mitochondrial membrane potential.RESULTS AND CONCLUSION:Alkaline phosphatase staining indicated that the most beneficial treatment for bone marrow mesenchymal stem cell osteogenesis was pretreatment with 10 μmol/L dimethylglyoxal glycine for 24 hours.Compared with the control group,the experimental group showed enhanced alkaline phosphatase staining expression,increased alkaline phosphatase activity and osteogenic gene expression,reduced lipid droplet formation and adipogenic gene expression as indicated by oil red O staining,decreased mitochondrial reactive oxygen species production,increased co-localization of mitochondria and lysosomes,and elevated mitochondrial membrane potential.The results suggest that 10 μmol/L dimethylglyoxal glycine pretreatment can promote osteogenic differentiation of bone marrow mesenchymal stem cells,inhibit adipogenic differentiation,and enhance mitophagy.

BACKGROUND:The mesenchymal stem cell secretome contains bioactive substances,cytokines,and growth factors.Three-dimensional cell culture can regulate the secretion of these components,potentially enhancing the ability to promote injury repair.OBJECTIVE:To investigate the repair effect of three-dimensional cultured human umbilical cord mesenchymal stem cell secretome on skin injuries in mice.METHODS:Human umbilical cord mesenchymal stem cells were cultured in conventional two-dimensional culture dishes and 96-well U-bottom cell culture plates,from which their secretory components were subsequently collected.The expression of skin damage repair related secretory factors in umbilical cord mesenchymal stem cells was analyzed using RT-qPCR.The protein expression level of skin damage repair related factors in umbilical cord mesenchymal stem cell secretome was detected using enzyme-linked immunosorbent assay.The potential of human umbilical cord mesenchymal stem cell secretome to repair vascular injuries was evaluated using an immortalized human umbilical vein endothelial cell migration model.A mouse skin injury model was established,and the human umbilical cord mesenchymal stem cell secretome was injected subcutaneously.Repair effects on skin injury were assessed through wound healing rates and histopathological analysis.RESULTS AND CONCLUSION:(1)After three days of cultivation,human umbilical cord mesenchymal stem cells cultured in two dimensions exhibited a fibroblast-like,swirling growth pattern,whereas three-dimensional culture led to the formation of uniform microspheres.(2)Compared with two-dimensional culture,three-dimensional culture significantly increased the mRNA expression of transforming growth factor β and basic fibroblast growth factor in human umbilical cord mesenchymal stem cells.(3)Compared with two-dimensional culture,three-dimensional cultured human umbilical cord mesenchymal stem cell secretome significantly enhanced the protein expression of vascular endothelial growth factor,interleukin-10,and granulocyte-macrophage colony-stimulating factor in the human umbilical cord mesenchymal stem cell secretome.(4)Compared with two-dimensional culture,three-dimensional cultured human umbilical cord mesenchymal stem cell secretome significantly promoted the migration of immortalized human umbilical cord mesenchymal stem cells.(5)Compared with the untreated control group and the two-dimensional cultured human umbilical cord mesenchymal stem cell secretome,the three-dimensional cultured human umbilical cord mesenchymal stem cell secretome can significantly accelerate the skin wound healing rate and wound skin structure remodeling in mice.These results indicate that three-dimensional culture can enhance the expression of paracrine factors of human umbilical cord mesenchymal stem cells,and their secretome can significantly promote the repair of mouse skin damage.

OBJECTIVE:Elevated blood pressure increases the risk of cardiovascular diseases.Isometric exercise training has been shown to significantly reduce resting blood pressure,but the factors influencing its effectiveness remain unclear,and specific application guidelines are yet to be established.This study aims to evaluate the impact of isometric exercise training on resting blood pressure through meta-analysis,explore its moderating factors,and provide evidence-based recommendations based on its dose-response relationship.METHODS:Following the PRISMA guidelines,a systematic search was conducted in PubMed,Embase,Cochrane Library,Scopus,and Web of Science databases using keywords"Isometric exercise training,""Systolic blood pressure,"and"Diastolic blood pressure,"covering literature up to September 2024.Randomized controlled trials involving isometric exercise training and resting blood pressure were included.Three independent researchers performed literature screening and data extraction,assessing bias risk and quality grades using the Risk of Bias 2.0 tool and GRADE framework.Main effect pooling,publication bias assessment,subgroup,and regression analysis were conducted using R software(version 4.3.4).RESULTS:A total of 28 articles(comprising 32 randomized controlled trials)involving 977 participants were included.(1)Meta-analysis results indicated that isometric exercise training significantly reduced resting systolic blood pressure(MD=-8.01,95％CI=-9.22 to-6.80,P＜0.01,I2=18.20％,low evidence grade)and diastolic blood pressure(MD=-3.46,95％CI=-4.64 to-2.28,P＜0.01,I2=0％,moderate evidence grade)compared to no exercise.(2)Subgroup analysis results revealed significant influences of gender,health status,exercise modality,frequency,intensity,duration,sets per session,rest duration,and baseline blood pressure on the main effects for both systolic(P＜0.01)and diastolic blood pressure(P＜0.05).(3)Regression analysis results did not show any significant influencing factors,but body mass index(β=-4.11,P=0.091)showed a significant negative trend on the main effect for systolic blood pressure.(4)No significant publication bias was observed in the meta-analysis results(P＞0.05).CONCLUSION:(1)Isometric exercise training significantly lowers systolic(low evidence grade)and diastolic(moderate evidence grade)blood pressure with clinically meaningful thresholds.(2)Participant characteristics(gender,health status,baseline blood pressure,and body mass index)and isometric exercise training protocols(modality,frequency,intensity,duration,cycle,sets per session,and rest duration)influence its antihypertensive effects.(3)The article recommends the optimal blood pressure management prescription:three sessions per week,with four sets per session,each set lasting 2 minutes with a 2-minute rest,at an intensity of 95％HRpeak using isometric wall squat exercises;the intervention period can be adjusted around a 6-week node.Future high-quality research is urgently needed to further validate and support these conclusions.

OBJECTIVE:Some studies have shown that physical exercise can effectively improve knee extensor strength and cardiorespiratory function in burn patients;some studies have also shown that physical exercise is not effective in improving respiratory function in burn patients.Improvement effects of physical exercise on physical functions(muscle function,walking function,cardiopulmonary function,and lean body mass)of burn patients were evaluated by a systematic evaluation and meta-analysis.METHODS:Based on databases including Web of Science,PubMed,Embase,Cochrane Library,CNKI,WanFang,and the Chinese Biomedical Database,literature on the improvement of physical function in burn patients through physical exercise was searched using subject headings and free terms.With muscle function,walking ability,cardiopulmonary function,and lean body mass as the primary outcome measures,a meta-analysis was conducted to compare the efficacy of physical exercise with traditional physical therapy or conventional care methods.RESULTS:A total of 38 papers were included,of which 26 papers were included in the meta-analysis,involving 1 658 patients.Meta-analysis results showed that:(1)Physical exercise significantly enhances the knee extensor strength of the dominant leg in burn patients(mean difference[MD]=8.34,95％confidence interval[CI]:6.95-9.72,P＜0.000 01),increases quadriceps strength,peak oxygen uptake,forced vital capacity and maximum ventilation volume in 1 second,and resting heart rate(standardized mean difference[SMD]=4.41,95％CI:2.52-6.30,P＜0.000 01;MD=4.91,95％CI:3.52-6.29,P＜0.000 01;MD=5.86,95％CI:0.09-11.63,P=0.05;MD=6.90,95％CI:2.93-10.87,P=0.000 7;MD=5.03,95％CI:1.45-8.61,P=0.006),and improves the 6-minute walking distance,gait parameters,and total lean body mass(MD=45.29,95％CI:24.7-65.89,P＜0.0001;SMD=7.84,95％CI:6.05-9.63,P＜0.000 01;MD=2.47,95％CI:2.01-2.93,P＜0.000 01).(2)The subgroup analysis results indicated that the improvement in knee extensor strength of the dominant leg may be better in children than in adults and better in the extra-heavy group than in the heavy group.Improvement in the 6-minute walking distance is better in children than in adults,and higher degree of burn indicates better improvement effects,with no difference from the control group for＜12 weeks.Peak oxygen uptake may be better in adults and severe burn groups than in children and moderate burn groups,resistance combined with aerobic exercise modalities may be better than aerobic exercise alone,and exercise duration＞60 minutes may be better than＜60 minutes.CONCLUSION:Physical activity is effective in improving physical function in burn patients,as evidenced by improvements in muscle strength,walking ability,cardiorespiratory fitness,and lean body mass.The quality of evidence recommended for all indicator results is moderate or below,with imprecision and inconsistency being the main factors for downgrading.Therefore,more high-quality randomized controlled trials are needed in the future to verify the reliability of the results.

BACKGROUND:Bone marrow mesenchymal stem cells play a crucial role in treatment of diseases,such as femoral head necrosis,and the therapeutic efficacy is closely related to the quality of the cells.The empowerment of cells has become a research focus.OBJECTIVE:To investigate the effects of hypoxia mimetic dimethylglyoxal glycine pretreatment on mitophagy and differentiation capacity of human bone marrow mesenchymal stem cells.METHODS:Bone marrow mesenchymal stem cells were extracted from the bone marrow of patients' iliac crest and cultured in vitro to the third passage.The cells were treated with dimethylglyoxal glycine at 0,10,50,and 100 μmol/Lfor 24 hours,followed by the replacement with an osteogenic induction differentiation medium,which constituted the pretreatment group.The continuous treatment group was cultured directly in osteogenic induction medium containing 0,10,50,and 100 μmol/L dimethylglyoxal glycine after cell adhesion.After 7 days of induction,alkaline phosphatase staining was performed to select the most favorable conditions for osteogenic differentiation for subsequent experiments,with normally cultured bone marrow mesenchymal stem cells serving as the control group.Alkaline phosphatase staining,alkaline phosphatase activity,oil red O staining,and related RT-qPCR were used to evaluate the osteogenic and adipogenic differentiation differences of bone marrow mesenchymal stem cells between the two groups.MitoSox staining was used to detect mitochondrial reactive oxygen species levels.Mito-tracker and Lyso-tracker staining were used to detect the co-localization of mitochondria and lysosomes.The fluorescent probe JC-1 was used to measure mitochondrial membrane potential.RESULTS AND CONCLUSION:Alkaline phosphatase staining indicated that the most beneficial treatment for bone marrow mesenchymal stem cell osteogenesis was pretreatment with 10 μmol/L dimethylglyoxal glycine for 24 hours.Compared with the control group,the experimental group showed enhanced alkaline phosphatase staining expression,increased alkaline phosphatase activity and osteogenic gene expression,reduced lipid droplet formation and adipogenic gene expression as indicated by oil red O staining,decreased mitochondrial reactive oxygen species production,increased co-localization of mitochondria and lysosomes,and elevated mitochondrial membrane potential.The results suggest that 10 μmol/L dimethylglyoxal glycine pretreatment can promote osteogenic differentiation of bone marrow mesenchymal stem cells,inhibit adipogenic differentiation,and enhance mitophagy.

BACKGROUND:The mesenchymal stem cell secretome contains bioactive substances,cytokines,and growth factors.Three-dimensional cell culture can regulate the secretion of these components,potentially enhancing the ability to promote injury repair.OBJECTIVE:To investigate the repair effect of three-dimensional cultured human umbilical cord mesenchymal stem cell secretome on skin injuries in mice.METHODS:Human umbilical cord mesenchymal stem cells were cultured in conventional two-dimensional culture dishes and 96-well U-bottom cell culture plates,from which their secretory components were subsequently collected.The expression of skin damage repair related secretory factors in umbilical cord mesenchymal stem cells was analyzed using RT-qPCR.The protein expression level of skin damage repair related factors in umbilical cord mesenchymal stem cell secretome was detected using enzyme-linked immunosorbent assay.The potential of human umbilical cord mesenchymal stem cell secretome to repair vascular injuries was evaluated using an immortalized human umbilical vein endothelial cell migration model.A mouse skin injury model was established,and the human umbilical cord mesenchymal stem cell secretome was injected subcutaneously.Repair effects on skin injury were assessed through wound healing rates and histopathological analysis.RESULTS AND CONCLUSION:(1)After three days of cultivation,human umbilical cord mesenchymal stem cells cultured in two dimensions exhibited a fibroblast-like,swirling growth pattern,whereas three-dimensional culture led to the formation of uniform microspheres.(2)Compared with two-dimensional culture,three-dimensional culture significantly increased the mRNA expression of transforming growth factor β and basic fibroblast growth factor in human umbilical cord mesenchymal stem cells.(3)Compared with two-dimensional culture,three-dimensional cultured human umbilical cord mesenchymal stem cell secretome significantly enhanced the protein expression of vascular endothelial growth factor,interleukin-10,and granulocyte-macrophage colony-stimulating factor in the human umbilical cord mesenchymal stem cell secretome.(4)Compared with two-dimensional culture,three-dimensional cultured human umbilical cord mesenchymal stem cell secretome significantly promoted the migration of immortalized human umbilical cord mesenchymal stem cells.(5)Compared with the untreated control group and the two-dimensional cultured human umbilical cord mesenchymal stem cell secretome,the three-dimensional cultured human umbilical cord mesenchymal stem cell secretome can significantly accelerate the skin wound healing rate and wound skin structure remodeling in mice.These results indicate that three-dimensional culture can enhance the expression of paracrine factors of human umbilical cord mesenchymal stem cells,and their secretome can significantly promote the repair of mouse skin damage.

OBJECTIVE:Elevated blood pressure increases the risk of cardiovascular diseases.Isometric exercise training has been shown to significantly reduce resting blood pressure,but the factors influencing its effectiveness remain unclear,and specific application guidelines are yet to be established.This study aims to evaluate the impact of isometric exercise training on resting blood pressure through meta-analysis,explore its moderating factors,and provide evidence-based recommendations based on its dose-response relationship.METHODS:Following the PRISMA guidelines,a systematic search was conducted in PubMed,Embase,Cochrane Library,Scopus,and Web of Science databases using keywords"Isometric exercise training,""Systolic blood pressure,"and"Diastolic blood pressure,"covering literature up to September 2024.Randomized controlled trials involving isometric exercise training and resting blood pressure were included.Three independent researchers performed literature screening and data extraction,assessing bias risk and quality grades using the Risk of Bias 2.0 tool and GRADE framework.Main effect pooling,publication bias assessment,subgroup,and regression analysis were conducted using R software(version 4.3.4).RESULTS:A total of 28 articles(comprising 32 randomized controlled trials)involving 977 participants were included.(1)Meta-analysis results indicated that isometric exercise training significantly reduced resting systolic blood pressure(MD=-8.01,95％CI=-9.22 to-6.80,P＜0.01,I2=18.20％,low evidence grade)and diastolic blood pressure(MD=-3.46,95％CI=-4.64 to-2.28,P＜0.01,I2=0％,moderate evidence grade)compared to no exercise.(2)Subgroup analysis results revealed significant influences of gender,health status,exercise modality,frequency,intensity,duration,sets per session,rest duration,and baseline blood pressure on the main effects for both systolic(P＜0.01)and diastolic blood pressure(P＜0.05).(3)Regression analysis results did not show any significant influencing factors,but body mass index(β=-4.11,P=0.091)showed a significant negative trend on the main effect for systolic blood pressure.(4)No significant publication bias was observed in the meta-analysis results(P＞0.05).CONCLUSION:(1)Isometric exercise training significantly lowers systolic(low evidence grade)and diastolic(moderate evidence grade)blood pressure with clinically meaningful thresholds.(2)Participant characteristics(gender,health status,baseline blood pressure,and body mass index)and isometric exercise training protocols(modality,frequency,intensity,duration,cycle,sets per session,and rest duration)influence its antihypertensive effects.(3)The article recommends the optimal blood pressure management prescription:three sessions per week,with four sets per session,each set lasting 2 minutes with a 2-minute rest,at an intensity of 95％HRpeak using isometric wall squat exercises;the intervention period can be adjusted around a 6-week node.Future high-quality research is urgently needed to further validate and support these conclusions.

Objective To analyze the genetic characteristics and variations of influenza A (H3N2) viruses in Ma'anshan from 2022 to 2024, and to provide a scientific basis for local influenza prevention and control. Methods From April 2022 to March 2024, influenza-like illness (ILI) specimens were collected from three national influenza surveillance sentinel hospitals in Ma’anshan. Samples positive for influenza by real-time PCR were subjected to virus culture and identification. A total of 40 representative A/H3N2 strains with hemagglutination titers ≥8 were selected for whole-genome sequencing. Genetic evolution, homology, amino acid variations, and glycosylation sites were analyzed. Results All H3N2 representative strains from the 2022–2023 influenza season belonged to clade 3C.2a1b.2a.1a.1, while those from the 2023–2024 season fell into clade 3C.2a1b.2a.2a.3a.1. The nucleotide and amino acid sequence similarities of HA and NA between the 40 representative strains and the vaccine strain A/Darwin/6/2021 were all above 97.35%. Compared with the vaccine strain, amino acid mutations were identified in antigenic sites A, B, C, and E, as well as in receptor-binding sites of the HA protein. An I222V substitution was detected in the NA protein. The HA protein contained four additional glycosylation sites compared to the vaccine strain, while the glycosylation pattern of the NA protein remained consistent. Conclusion No antigenic drift was observed in the influenza A/H3N2 viruses in Ma'anshan City from 2022 to 2024, but genetic changes such as branching variations, key amino acid substitutions, and an increase in HA glycosylation sites were observed. These findings underscore the importance of sustained molecular surveillance of local influenza viruses.

ObjectiveDiscriminating atypical hepatocellular carcinoma (HCC) from other malignancies in liver nodules classified as Liver Imaging Reporting and Data System category M (LR-M) remains a significant diagnostic challenge on conventional ultrasound examination. The LR-M category, originally intended to capture non-HCC malignancies, paradoxically contains up to 63% of atypical HCCs that deviate from classic enhancement patterns, leading to potential misdiagnosis and suboptimal treatment planning. While deep learning has shown promise in HCC diagnosis, most existing models rely exclusively on single-modality ultrasound, overlooking the diagnostic benefits of integrating complementary information from multiple imaging sources. To address this gap, we propose a novel attention-weighted tri-modal ultrasound network (TUS-Net) that integrates contrast-enhanced ultrasound (CEUS), B-mode ultrasound (BUS), and time-intensity curves (TICs) to improve diagnostic accuracy for these clinically challenging lesions. MethodsOur framework incorporates a three-dimensional convolutional neural network (C3D) backbone to extract spatiotemporal features from CEUS videos, capturing dynamic vascular patterns critical for lesion characterization. To effectively fuse complementary modalities, we introduce a dual-channel feature fusion module (DCFFM) that adaptively combines features from CEUS and BUS through channel-wise attention mechanisms, allowing the model to dynamically weigh the contribution of each modality based on diagnostic relevance. Additionally, we propose a temporal intensity feature fusion module (TIFFM) that leverages quantitative hemodynamic information from TICs to guide the model’s attention toward diagnostically critical temporal phases, such as arterial wash-in and portal venous washout. The model is further enhanced by automated lesion localization using YOLOX and class activation mapping for interpretability, ensuring that predictions align with clinically meaningful imaging features. ResultsEvaluated on a tri-modal ultrasound dataset comprising 161 patients with pathologically confirmed LR-M nodules (131 atypical HCC and 30 non-HCC malignancies), our model achieved an accuracy of 86.83%, a sensitivity of 92.50%, a specificity of 75.50%, and an AUC of 89.32% in screening atypical HCC. Compared to single-modality baselines, TUS-Net demonstrated superior specificity, a clinically critical metric given the higher risk associated with misclassifying non-HCC malignancies. Ablation studies confirmed the contribution of each module, with the full model outperforming both standard C3D and 3D ResNet backbones integrated with attention mechanisms. A reader study involving junior and senior radiologists further validated the clinical utility of AI assistance, showing consistent improvements in specificity and inter-reader consistency, particularly for less experienced clinicians. ConclusionThese results surpass existing benchmark models and demonstrate the potential of our approach to enhance diagnostic precision in clinically specific cases. By intelligently fusing multi-modal ultrasound data with attention-guided mechanisms, TUS-Net offers a reliable and interpretable tool that holds promise for improving the non-invasive diagnosis of atypical HCC in challenging LR-M liver nodules.

ObjectiveDiscriminating atypical hepatocellular carcinoma (HCC) from other malignancies in liver nodules classified as Liver Imaging Reporting and Data System category M (LR-M) remains a significant diagnostic challenge on conventional ultrasound examination. The LR-M category, originally intended to capture non-HCC malignancies, paradoxically contains up to 63% of atypical HCCs that deviate from classic enhancement patterns, leading to potential misdiagnosis and suboptimal treatment planning. While deep learning has shown promise in HCC diagnosis, most existing models rely exclusively on single-modality ultrasound, overlooking the diagnostic benefits of integrating complementary information from multiple imaging sources. To address this gap, we propose a novel attention-weighted tri-modal ultrasound network (TUS-Net) that integrates contrast-enhanced ultrasound (CEUS), B-mode ultrasound (BUS), and time-intensity curves (TICs) to improve diagnostic accuracy for these clinically challenging lesions. MethodsOur framework incorporates a three-dimensional convolutional neural network (C3D) backbone to extract spatiotemporal features from CEUS videos, capturing dynamic vascular patterns critical for lesion characterization. To effectively fuse complementary modalities, we introduce a dual-channel feature fusion module (DCFFM) that adaptively combines features from CEUS and BUS through channel-wise attention mechanisms, allowing the model to dynamically weigh the contribution of each modality based on diagnostic relevance. Additionally, we propose a temporal intensity feature fusion module (TIFFM) that leverages quantitative hemodynamic information from TICs to guide the model’s attention toward diagnostically critical temporal phases, such as arterial wash-in and portal venous washout. The model is further enhanced by automated lesion localization using YOLOX and class activation mapping for interpretability, ensuring that predictions align with clinically meaningful imaging features. ResultsEvaluated on a tri-modal ultrasound dataset comprising 161 patients with pathologically confirmed LR-M nodules (131 atypical HCC and 30 non-HCC malignancies), our model achieved an accuracy of 86.83%, a sensitivity of 92.50%, a specificity of 75.50%, and an AUC of 89.32% in screening atypical HCC. Compared to single-modality baselines, TUS-Net demonstrated superior specificity, a clinically critical metric given the higher risk associated with misclassifying non-HCC malignancies. Ablation studies confirmed the contribution of each module, with the full model outperforming both standard C3D and 3D ResNet backbones integrated with attention mechanisms. A reader study involving junior and senior radiologists further validated the clinical utility of AI assistance, showing consistent improvements in specificity and inter-reader consistency, particularly for less experienced clinicians. ConclusionThese results surpass existing benchmark models and demonstrate the potential of our approach to enhance diagnostic precision in clinically specific cases. By intelligently fusing multi-modal ultrasound data with attention-guided mechanisms, TUS-Net offers a reliable and interpretable tool that holds promise for improving the non-invasive diagnosis of atypical HCC in challenging LR-M liver nodules.