BACKGROUND:Sarcopenia is an age-related condition characterized by the loss of skeletal muscle mass,strength,and/or physical function.Currently,effective treatments for sarcopenia remain limited.A new therapeutic approach to improve symptoms and prognosis of sarcopenia patients clinically was important.OBJECTIVE:To explore the effects of canine adipose-derived mesenchymal stem cells and their exosomes on a dexamethasone-induced sarcopenia in mice.METHODS:Mesenchymal stem cells were isolated and cultured from canine adipose tissue,and identified and functionally evaluated through flow cytometry and differentiation assays for osteogenesis,adipogenesis,and chondrogenesis.Subsequently,exosomes from adipose-derived mesenchymal stem cells were extracted and characterized using transmission electron microscopy,western blot assay,and nanocoulter tracking analysis.In vitro,the effects of canine adipose-derived mesenchymal stem cells and their exosomes on myotube growth and the expression of muscle atrophy-related genes were investigated using dexamethasone-induced C2C12 myotube atrophy and aging C2C12 models.In vivo,a dexamethasone-induced mouse sarcopenia model was established and received intraperitoneal or intravenous injection of canine adipose-derived mesenchymal stem cells.Therapeutic efficacy was assessed through mouse rotarod performance,histopathological analysis,and muscle atrophy-related genes testing.RESULTS AND CONCLUSION:(1)The isolated canine adipose-derived mesenchymal stem cells highly expressed CD73,CD90,and CD105,and lowly expressed MHC-Ⅱ,CD14,CD19,CD34,and CD45,and successfully differentiated into osteoblasts,adipocytes,and chondrocytes in vitro.(2)The adipose-derived mesenchymal stem cells-derived exosomes met the identification criteria in terms of particle size,electron microscopy morphology,and positive expression of specific markers.(3)Compared to the dexamethasone-induced C2C12 atrophy group,treatment with adipose-derived mesenchymal stem cells and their exosomes promoted the recovery and growth of myotubes,inhibited the expression of muscle atrophy-related genes MuRF1 and Atrogin-1.(4)Compared to the aging C2C12 group,adipose-derived mesenchymal stem cells and their exosomes significantly enhanced the recovery and growth of aged muscle tubes in aging cells.(5)Compared to the control group,the rotarod time in dexamethasone-induced sarcopenia model mice was significantly decreased(P＜0.01).After 7 days(P＜0.01,P＜0.01)and 10 days(P＜0.01,P＜0.05)of adipose-derived mesenchymal stem cells treatment via intraperitoneal and intravenous injection,rotarod time was significantly increased,respectively.After 14 days,all treatment groups showed longer rotarod times than the model group,although with no significant differences between them.(6)Compared to the control group,the cross-sectional area of anterior tibial muscle in the model group was significantly reduced(P＜0.01),and it was significantly increased after intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells(P＜0.05,P＜0.01).(7)Compared to the model group,intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells significantly inhibited the mRNA expression of MuRF1 and Atrogin-1 genes(P＜0.01,P＜0.01,P＜0.01,P＜0.01).The results indicated that adipose-derived mesenchymal stem cells and their exosomes promoted recovery and growth of atrophic myotube cells by inhibiting the expression of muscle atrophy-related genes,and both intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells provided good therapeutic effects on sarcopenia in mice.

BACKGROUND:Sarcopenia is an age-related condition characterized by the loss of skeletal muscle mass,strength,and/or physical function.Currently,effective treatments for sarcopenia remain limited.A new therapeutic approach to improve symptoms and prognosis of sarcopenia patients clinically was important.OBJECTIVE:To explore the effects of canine adipose-derived mesenchymal stem cells and their exosomes on a dexamethasone-induced sarcopenia in mice.METHODS:Mesenchymal stem cells were isolated and cultured from canine adipose tissue,and identified and functionally evaluated through flow cytometry and differentiation assays for osteogenesis,adipogenesis,and chondrogenesis.Subsequently,exosomes from adipose-derived mesenchymal stem cells were extracted and characterized using transmission electron microscopy,western blot assay,and nanocoulter tracking analysis.In vitro,the effects of canine adipose-derived mesenchymal stem cells and their exosomes on myotube growth and the expression of muscle atrophy-related genes were investigated using dexamethasone-induced C2C12 myotube atrophy and aging C2C12 models.In vivo,a dexamethasone-induced mouse sarcopenia model was established and received intraperitoneal or intravenous injection of canine adipose-derived mesenchymal stem cells.Therapeutic efficacy was assessed through mouse rotarod performance,histopathological analysis,and muscle atrophy-related genes testing.RESULTS AND CONCLUSION:(1)The isolated canine adipose-derived mesenchymal stem cells highly expressed CD73,CD90,and CD105,and lowly expressed MHC-Ⅱ,CD14,CD19,CD34,and CD45,and successfully differentiated into osteoblasts,adipocytes,and chondrocytes in vitro.(2)The adipose-derived mesenchymal stem cells-derived exosomes met the identification criteria in terms of particle size,electron microscopy morphology,and positive expression of specific markers.(3)Compared to the dexamethasone-induced C2C12 atrophy group,treatment with adipose-derived mesenchymal stem cells and their exosomes promoted the recovery and growth of myotubes,inhibited the expression of muscle atrophy-related genes MuRF1 and Atrogin-1.(4)Compared to the aging C2C12 group,adipose-derived mesenchymal stem cells and their exosomes significantly enhanced the recovery and growth of aged muscle tubes in aging cells.(5)Compared to the control group,the rotarod time in dexamethasone-induced sarcopenia model mice was significantly decreased(P＜0.01).After 7 days(P＜0.01,P＜0.01)and 10 days(P＜0.01,P＜0.05)of adipose-derived mesenchymal stem cells treatment via intraperitoneal and intravenous injection,rotarod time was significantly increased,respectively.After 14 days,all treatment groups showed longer rotarod times than the model group,although with no significant differences between them.(6)Compared to the control group,the cross-sectional area of anterior tibial muscle in the model group was significantly reduced(P＜0.01),and it was significantly increased after intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells(P＜0.05,P＜0.01).(7)Compared to the model group,intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells significantly inhibited the mRNA expression of MuRF1 and Atrogin-1 genes(P＜0.01,P＜0.01,P＜0.01,P＜0.01).The results indicated that adipose-derived mesenchymal stem cells and their exosomes promoted recovery and growth of atrophic myotube cells by inhibiting the expression of muscle atrophy-related genes,and both intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells provided good therapeutic effects on sarcopenia in mice.

Nonunion of osteoporotic vertebral fractures (OVF), predominantly affecting the elderly, can lead to intractable pain, vertebral collapse, progressive kyphotic deformity, and neurological impairment, significantly compromising patients′ quality of life. There exists considerable debate on diagnosis and management of OVF, encompassing key issues such as clinical diagnosis and staging criteria for nonunion, surgical indications and procedure selection, and postoperative rehabilitation planning. Currently, there lacks standardized clinical guideline and expert consensus on the diagnosis and management of OVF nonunion in China. To address this gap, Minimally Invasive Surgery Group of Chinese Orthopedic Association, Osteoporosis Committee of Chinese Association of Orthopedic Surgeons, Prevention and Rehabilitation Committee for Osteoporosis of Chinese Association of Rehabilitation Medicine and Minimally Invasive Orthopedic Surgery Branch of China Association for Geriatric Care jointly organized domestic experts in spinal surgery, endocrinology, and rehabilitation to formulate the Clinical guideline for the diagnosis and treatment for nonunion of osteoporotic vertebral fractures ( version 2025), based on existing literature and clinical experience and adhering to principles of scientific rigor and practicality. The guideline provided 13 evidence-based recommendations encompassing diagnosis and treatment of OVF nonunion, aiming to standardize its clinical management.

Objective To establish a human luminal breast cancer stem cell(BCSC)model and investigate the inhibitory effects of astragaloside Ⅳ(AS-Ⅳ)on BCSC growth.Methods MCF-7 breast cancer cells were cultured in stem cell-specific medium to induce BCSC formation.The BCSCs were then divided into a blank control group and an AS-Ⅳ treatment group,both groups were given PBS or AS-Ⅳ treatment.Morphological changes were observed after intervention.The therapeutic efficacy of AS-Ⅳ was evaluated using 3D spheroid formation and cell viability assays.Transcriptomic profiling and gene expression analysis were performed to elucidate the underlying mechanisms.Results Compared with the MCF7 breast cancer cells,MCF7 breast cancer stem cell mammospheres exhibited accelerated growth(P＜0.01)and significantly increased expression of the stemness marker ALDH1A1(P＜0.01).Further comparison with the blank control group revealed that astragaloside Ⅳ(AS-Ⅳ)treatment significantly inhibited MCF7 breast cancer stem cell proliferation(P＜0.001)and slowed mammosphere growth(P＜0.01).Transcriptomic analysis demonstrated that differentially expressed genes(DEGs)induced by stem cell modeling and AS-Ⅳ intervention were enriched in the cellular senescence signaling pathway.AS-Ⅳ intervention substantially increased the number of SA-β-gal-positive cells(P＜0.01).RT-PCR analysis confirmed that AS-Ⅳsignificantly upregulated mRNA expression of IL-1α(P＜0.01),P21(P＜0.001),and P53(P＜0.05)in MCF7 breast cancer stem cells.Conclusion Astragaloside Ⅳ suppresses the growth of human luminal breast cancer stem cells by inducing cellular senescence.

Nonunion of osteoporotic vertebral fractures (OVF), predominantly affecting the elderly, can lead to intractable pain, vertebral collapse, progressive kyphotic deformity, and neurological impairment, significantly compromising patients′ quality of life. There exists considerable debate on diagnosis and management of OVF, encompassing key issues such as clinical diagnosis and staging criteria for nonunion, surgical indications and procedure selection, and postoperative rehabilitation planning. Currently, there lacks standardized clinical guideline and expert consensus on the diagnosis and management of OVF nonunion in China. To address this gap, Minimally Invasive Surgery Group of Chinese Orthopedic Association, Osteoporosis Committee of Chinese Association of Orthopedic Surgeons, Prevention and Rehabilitation Committee for Osteoporosis of Chinese Association of Rehabilitation Medicine and Minimally Invasive Orthopedic Surgery Branch of China Association for Geriatric Care jointly organized domestic experts in spinal surgery, endocrinology, and rehabilitation to formulate the Clinical guideline for the diagnosis and treatment for nonunion of osteoporotic vertebral fractures ( version 2025), based on existing literature and clinical experience and adhering to principles of scientific rigor and practicality. The guideline provided 13 evidence-based recommendations encompassing diagnosis and treatment of OVF nonunion, aiming to standardize its clinical management.

Objective To study the influence of long term simulated weightlessness on occurrence of laryngopharyngeal reflux(LPR)in healthy volunteers by detection of pepsin in saliva.Methods During a 90-day head-down tilt bed rest(HDTBR)experiment,11 volunteers(4 from the control group and 7 from the countermeasure group)were recruited in the study in the following seven sessions:before bed rest session(Pre),during bed rest sessions for 3 days(BR3),31 days(BR31),61 days(BR61),85 days(BR85)and post bed rest sessions for 7 days(R7)and 25 days(R25).During each testing session,saliva samples were collected for two consecutive days both in the morning and at night before sleeping.Then pepsin in the saliva was measured by enzyme-linked immunosorbent assay.Scale of otorhinolaryngological symptoms for the duration of"Pre-,During-and Post-"were retrospectively performed.Results Among 288 saliva samples of 11 volunteers,17 saliva samples of 8 volunteers were positive for pepsin.The incidence of LPR was 9.1%(1/11)in the Pre session,and it increased to 36.4%in the BR31 session which was higher than the following consequential sessions(0%in BR31,27.3%in BR61 and 27.3%in BR85).Intriguingly,it rose again to 45.5%in R7 session and decreased to 9.1%until in R25 session.There was no significant difference between the control group and the countermeasure group.Total scores for the scale of otorhinolaryngological symptoms showed that a slight elevation tendency emerged during HDTBR session,compared with the pre-HDTBR session.It recovered during the post bed rest sessions.Conclusion The laryngopharyngeal reflux was found in the Pre,During and Post HDTBR experiment.The incidence was significantly increased both in the BR3 and R7 sessions,which indicates that the change of the posture with the stimulation of gastrointestinal dynamic conditions,despite the changes from vertical to horizontal or from horizontal to vertical,might be the major impact factor contributing to the elevation tendency of the incidence of laryngopharyngeal reflux.

This study aims to explore possible effect of RNA polymerase I subunit D (POLR1D) on proliferation and angiogenesis ability of colorectal cancer (CRC) cells and mechanism herein. The correlation of POLR1D and Yin Yang 1 (YY1) expressions with prognosis of CRC patients in TCGA database was analyzed. Quantitative realtime polymerase chain reaction (qRT-PCR) and Western blot were applied to detect expression levels of POLR1D and YY1 in CRC cell lines and CRC tissues. SW480 and HT-29 cells were transfected with si-POLR1D or pcDNA3.1-POLR1D to achieve POLR1D suppression or overexpression before cell migration, angiogenesis of human umbilical vein endothelial cells were assessed. Western blot was used to detect expressions of p38 MAPK signal pathway related proteins and interaction of YY1 with POLR1D was confirmed by dual luciferase reporter gene assay and chromatin immunoprecipitation (ChIP). TCGA data showed that both POLR1D and YY1 expressions were up-regulated in CRC patients. High expression of POLR1D was associated with poor prognosis of CRC patients. The results showed that POLR1D and YY1 were highly expressed in CRC cell lines. Inhibition or overexpression of POLR1D can respectively suppress or enhance proliferation and angiogenesis of CRC cells. YY1 inhibition can suppress CRC progression and deactivate p38 MAPK signal pathway, which can be counteracted by POLR1D overexpression. JASPAR predicted YY1 can bind with POLR1D promoter, which was confirmed by dual luciferase reporter gene assay and ChIP. YY1 transcription can up-regulate POLR1D expression to activate p38 MAPK signal pathway, thus promoting proliferation and angiogenesis ability of CRC cells.

With the broad application of high-resolution computed tomography (CT) and high rates of early lung cancer screening, the number of patients diagnosed with synchronous multiple primary lung cancer (sMPLC) has been increasing. It becomes of great prominence to distinct sMPLC from intrapulmonary metastases in clinical practice. An increasing number of studies have developed high-throughput sequencing based genetic approaches to specify the molecular characteristics of sMPLC, which contributes to a better understanding of its tumorigenesis. The genetic profile of sMPLC also benefits its diagnosis, which mainly relies on its clinicopathological criteria. Here, we summarize the progresses on the diagnostic criteria for sMPLC, and also molecular features of sMPLC from the perspective of clonality analysis.

Objective:To investigate the pathogenic distribution of benign infantile convulsions with mild gastroenteritis(BICE)and explore the relevance of serum cytokines and BICE.Methods:Eighty BICE infants admitted in Inner Mongolia Maternal and Child Health Hospital from January 2017 to December 2019 were selected as BICE group, and 80 mild gastroenteritis infants without convulsion attack were selected as control group during the same period.Fluorometric real-time PCR was used to detect the pathogen of enterovirus.Serum cytokines including interleukin(IL)-6, tumor necrosis factor(TNF)-α, IL-8 and soluble interleukin-2 receptor(SIL-2R)were detected by using chemiluminescence method.The relevance of frequency and duration of convulsion in infants with BICE and the indicators above were analyzed.Results:Rotavirus infection was the main cause of BICE during the study period in this region.Among 80 cases in the BICE group, rotavirus positive infants accounted for 38.8%(31/80) and norovirus positive infants accounted for 10.0%(8/80). The levels of IL-6, IL-8 and SIL-2R in the BICE group were prominently higher than those in the control group( P<0.05); the difference of TNF-α level between two groups had no statistical significance( P>0.05). The levels of IL-6, TNF -α, IL-8, SIL-2R in the group with convulsion attack times ≥ 2 and convulsion duration ≥5 min were higher than those in the group with convulsion attack times<2 and convulsion duration<5 min( P<0.05). The frequency and duration of convulsions were positively correlated with the levels of IL-6, TNF -α, IL-8 and SIL-2R( P<0.05). Conclusion:Rotavirus is the main pathogen of BICE in this region.There is immunologic imbalance in children with BICE, especially the changes of IL-6 and SIL-2R levels, which may provide effective cytological and experimental data evidence for judging progression and prognosis of the disease.