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.

Purpose To explore the correlation between spectral CT-derived quantitative parameters and different programmed death-ligand 1(PD-L1)expression status in gastric adenocarcinoma,in order to provide additional imaging-based references for immunotherapy regimen selection in patients with this disease.Materials and Methods A total of 45 patients with gastric adenocarcinoma,pathologically confirmed by biopsy,who underwent PD-L1 testing prior to treatment were retrospectively enrolled from Lanzhou University Second Hospital between January 2021 and September 2023.All patients underwent baseline spectral CT scans.Based on PD-L1 expression status,patients were categorized into the higher combined positive score(CPS)group(CPS≥5)and the lower CPS group(CPS<5).From the single-energy images of arterial and venous phases,the CT values(CT40 keV,CT70 keV),effective atomic number,and iodine concentration of the lesions were measured.The standardized iodine concentration and slope of the spectral curve were calculated.Differences in spectral CT parameters between the two groups were compared.Receiver operating characteristic curves were plotted for parameters with statistically significant differences,and the area under the curve was calculated to evaluate the efficacy of each single parameter and combined parameters in distinguishing PD-L1 expression status.Results In the arterial phase,the CT40 keV,CT70 keV,iodine concentration,standardized iodine concentration,effective atomic number,and slope of the spectral curve of lesions in the higher expression group were all significantly higher than those of lesions in the lower expression group(t/Z=-3.115 to-2.725,all P<0.05),whereas no significant differences were observed in all parameters in the venous phase(all P>0.05).For the standardized iodine concentration in the enhanced arterial phase,the area under the curve for distinguishing PD-L1 expression status was 0.755(95%CI 0.612 to 0.898),with a sensitivity of 81.8%and a specificity of 65.2%.No significant differences were found between it and other single spectral CT parameters in the arterial phase(all P>0.05),and its diagnostic efficacy was similar to that of the combined parameters[the area under the curve was 0.755(95%CI 0.613 to 0.897),sensitivity was 90.9%,specificity was 52.2%].Conclusion Quantitative parameters of spectral CT in the arterial phase can predict the PD-L1 expression of gastric adenocarcinoma,which may provide a reference for the screening and immunotherapy evaluation of patients with gastric adenocarcinoma.

Purpose To explore the correlation between spectral CT-derived quantitative parameters and different programmed death-ligand 1(PD-L1)expression status in gastric adenocarcinoma,in order to provide additional imaging-based references for immunotherapy regimen selection in patients with this disease.Materials and Methods A total of 45 patients with gastric adenocarcinoma,pathologically confirmed by biopsy,who underwent PD-L1 testing prior to treatment were retrospectively enrolled from Lanzhou University Second Hospital between January 2021 and September 2023.All patients underwent baseline spectral CT scans.Based on PD-L1 expression status,patients were categorized into the higher combined positive score(CPS)group(CPS≥5)and the lower CPS group(CPS<5).From the single-energy images of arterial and venous phases,the CT values(CT40 keV,CT70 keV),effective atomic number,and iodine concentration of the lesions were measured.The standardized iodine concentration and slope of the spectral curve were calculated.Differences in spectral CT parameters between the two groups were compared.Receiver operating characteristic curves were plotted for parameters with statistically significant differences,and the area under the curve was calculated to evaluate the efficacy of each single parameter and combined parameters in distinguishing PD-L1 expression status.Results In the arterial phase,the CT40 keV,CT70 keV,iodine concentration,standardized iodine concentration,effective atomic number,and slope of the spectral curve of lesions in the higher expression group were all significantly higher than those of lesions in the lower expression group(t/Z=-3.115 to-2.725,all P<0.05),whereas no significant differences were observed in all parameters in the venous phase(all P>0.05).For the standardized iodine concentration in the enhanced arterial phase,the area under the curve for distinguishing PD-L1 expression status was 0.755(95%CI 0.612 to 0.898),with a sensitivity of 81.8%and a specificity of 65.2%.No significant differences were found between it and other single spectral CT parameters in the arterial phase(all P>0.05),and its diagnostic efficacy was similar to that of the combined parameters[the area under the curve was 0.755(95%CI 0.613 to 0.897),sensitivity was 90.9%,specificity was 52.2%].Conclusion Quantitative parameters of spectral CT in the arterial phase can predict the PD-L1 expression of gastric adenocarcinoma,which may provide a reference for the screening and immunotherapy evaluation of patients with gastric adenocarcinoma.

Both morbidity and mortality of gastric cancer are in the front rank among malignant tumors.At present,enhanced CT is served as an important imaging method for preoperative diagnosis and assessment of gastric cancer,but it is mostly based on morphological evaluation and unable to perform quantitative analysis.The functional imaging technology represented by energy spectral CT and CT perfusion imaging has a variety of quantitative parameters,which is expected to make up for the shortcomings of conventional CT.The review introduces the basic principles of energy spectral CT and CT perfusion imaging,and summarizes their applications in the diagnosis,pathological classification,grading,staging and efficacy prediction of gastric cancer,aiming to improve the understanding of functional CT imaging for the pretreatment assessment in gastric cancer.

Gastrointestinal stromal tumors(GISTs)are the most common mesenchymal tumors of the gastrointestinal tract,and they are also genetically heterogeneous tumors.c-KIT gene or PDGFRA gene mutation is the main driving factor leading to its occurrence,and it is also one of the key factors affecting the treatment and prognosis of patients with GISTs.Imaging examination is non-invasive and can display tumors from multiple angles and directions,making it the main method for preoperative evaluation of GISTs.With the continuous development of imaging technology,non-invasive and definite genotyping of GISTs by imaging methods before surgery plays a positive role in the selection of targeted drugs and doses for patients and the evaluation of targeted treatment efficacy.This article reviews the imaging progress on the genotype of GISTs and the efficacy of targeted therapy.

Objective To explore the impact of puerarin treatment on autophagy in rats with traumatic brain injury (TBⅠ) and the underlying mechanism.Methods Seventy five Sprague-Dawley (SD) rats were randomized into 5 groups:sham group (S group,n =15),traumatic brain injury group (TBⅠ group,n =15),TBⅠ + puerarin treatment group (TBⅠ + Pue group,n =15),TBⅠ + JNK inhibitor group (TBⅠ + SP group,n =15),and TBⅠ + JNK activator + Pue (TBⅠ + An + Pue group,n =15).Feeney method was applied to make rats with TBⅠ model.Mter that,head water content and neurological deficit score (NDS) were measured and recorded at day 1,3 and 7 in each group.Western blot was used to measure the JNK activity and autophagic marker proteins,including LC3B and Beclin1.Results Compared to S group,the head water content and NDS were decreased significantly among the others (P ＜ 0.05).The head water content and NDS in TBⅠ + Pue and TBⅠ + SP groups was decreased remarkably compared with TBⅠ group.Combined with puerarin and animycin treatments failed to reduce head water content and NDS compared to the TBⅠ + Pue group.Activated autophagy could be observed in TBⅠ group compared to S group.Compared to group S,LC3Ⅱ,Beclin1 and P-JNK1 were increased significantly.Pue and SP could reduce their expressions,respectively.Combined with puerarin and animycin treatments failed to reduce LC3Ⅱ,Beclin1 and P-JNK1 compared to TBⅠ + Pue group.Conclusions Puerarin could protect rats with TBⅠ via inhibiting autophagy,JNK signal pathway could involve the process of puerarin regulating autophagy.