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.

X-ray is usually used to determine anatomy and localization during conventional permanent pacemaker implantation.But X-ray exposure might induce radiation injury to fetus.In this paper,we reported 2 cases successful double cavity permanent pacemaker implantation in pregnant women woman at 13 weeks of gestation under the guidance of transthoracic echocardiography.The postoperative pacing parameters were good,the whole process was finished with zero radiation,and there were complications during pregnancy.Both cases resulted in full-term pregnancies and the natural delivery of healthy newborns.Pacemaker electrodes were in normal position as confirmed by post-delivery X-ray examinations.

Aim To investigate the high expression of LINC00626 in colorectal cancer,and explore the effects of LINC00626 on the proliferation,apoptosis,and drug sensitivity of colorectal cancer SW480 cells,as well as its underlying mechanisms.Methods Flu-orescence in situ hybridization(FISH)was used to de-tect the expression levels of LINC00626 in 38 colorec-tal cancer tissues and their corresponding adjacent nor-mal tissues.The JASPAR database was utilized to pre-dict co-expressed genes and their possible binding sites.Cell transfection technology was employed to knockdown LINC00626.Western blot and qRT-PCR techniques were used to verify the transfection efficien-cy.CCK-8 assay,cell apoptosis and necrosis staining,and Western blot were used to detect the changes in the proliferation,apoptosis,drug sensitivity,and ap-optotic proteins of SW480 cells,respectively.Results The FISH results indicated that LINC00626 was highly expressed in colorectal cancer tissues(P＜0.05).The expression of LINC00626 was not associat-ed with the age or gender of patients,but was related to the TNM stage and the presence of lymph node me-tastasis($ P＜0.05 $).The results of CCK-8 assay and cell apoptosis and necrosis staining showed that af-ter knockdown of LINC00626,the proliferation ability of SW480 cells decreased,the apoptosis level in-creased,and the drug resistance decreased(P＜0.05).Western blot results showed that with the de-crease in the expression level of LINC00626,the ex-pression of caspase-3 protein decreased,the expression of cleaved caspase-3 protein increased,and the expres-sion of Bcl-2 protein decreased(P＜0.05).Conclu-sions LINC00626 is highly expressed in colorectal cancer and is associated with the TNM stage and the presence of lymph node metastasis.LINC00626 can af-fect the proliferation,apoptosis,and drug sensitivity of SW480 cells and alter the expression of apoptotic pro-teins.

Aim To investigate the expression levels of cytoplasmic FMR1-interacting protein-1(CYFIP1)in colorectal cancer and assess the impact of CYFIP1 interaction on the proliferation and apoptosis of colorec-tal cancer cell HT29,along with its potential mecha-nisms.Methods Immunohistochemistry was em-ployed to assess CYFIP1 expression in 32 colorectal cancer tissues and adjacent tissues.Coexpressed genes were identified using the GEPIA2 website to predict potential correlations and binding sites.Following the construction of a siRNA-CYFIP1,alterations in cell proliferation,apoptosis,and levels of apoptosis-related proteins were evaluated through CCK-8 assay,Hoechst 33342/PI double staining assay,and Western blot a-nalysis,respectively.Results The immunohisto-chemical findings revealed a significantly elevated level of CYFIP1 expression in colorectal cancer tissues com-pared to paracancer tissues(P＜0.05).The expres-sion of CYFIP1 did not show any correlation with age and gender,but exhibited associations with TNM stage and lymph node metastasis(P＜0.05).A conserved TP53 binding site was predicted in the 3kbps DNA re-gion upstream of the CYFIP1 gene using GEPIA2,JASPAR databases,and rVista 2.0 promoter prediction software.Following transfection of HT29 cells with siRNA-CYFIP1,the clonogenesis and proliferation of cells significantly decreased(P＜0.05).Additional-ly,the levels of cleaved caspase-3 were elevated,while the expression levels of caspase-3 and Bcl-2 were reduced after transfection with siRNA-CYFIP1(P＜0.05),which might be related to the interaction be-tween CYFIP1 and TP53.Conclusions The upregu-lation of CYFIP1 in colorectal cancer is associated with TNM stage and lymph node metastasis.Upon silen-cing,CYFIP1 demonstrates the ability to suppress pro-liferation in HT29 cells and modulate the expression of apoptotic proteins.

Objective To compare the clinical effect between cannulated compression countersunk head screws(CS)and anatomical locking compression hook plate(LCP)for fractures of proximal fifth metatarsal bone at Lawrence zone Ⅰ.Methods A total of 60 patients with fractures of proximal fifth metatarsal bone at Lawrence zone Ⅰ from May 2021 to May 2023 were retrospectively analyzed.Of them,20 patients were treated by internal fixation with cannulated compression countersunk head screws(CS group),and other 40 patients were treated by internal fixation with anatomical locking compression hook plate(LCP group).The postoperative therapeutic effects were evaluated by using the Visual Analogue Scale(VAS)and the American Orthopaedic Foot and Ankle Society(AOFAS)Midfoot Scale.Incidences of postoperative complications were also recorded.Results The operations were successfully completed in all the 60 patients.The operation time in the CS group was shorter than that in the LCP group[37(15-74)min vs.50.5(28-102)min,P=0.002].The VAS score in the CS group immediately after surgery was lower than that in the LCP group[3(2-5)vs.4(2-5),P=0.004],and there was no significant difference between the two groups at 3,6,and 12 months after surgery and at the last follow-up(P＞0.05).At the 3rd month after operation,the AOFAS score in the CS group was better than that in the LCP group[52(23-62)vs.49(23-62),P=0.038],and there was no significant difference between the two groups at 6 and 12 months after surgery and at the last follow-up(P＞0.05).In the LCP group,there were 1 case of superficial wound infection,3 cases of long-term chronic pain,6 cases of foreign body sensation,5 cases of removal of the internal fixation by a second operation after one year postoperatively.In the CS group,there was only 1 case of foreign body sensation.Conclusions Both cannulated compression countersunk head screws and anatomical locking compression hook plate can effectively fix fractures of proximal fifth metatarsal bone at Lawrence zone Ⅰ.Compared with anatomical locking compression hook plate,cannulated compression countersunk head screws can shorten operation time,reduce postoperative pain,and facilitate early functional rehabilitation.

Theory and technology of Medical Immunology are widely used in scientific research.Our teaching and research group uses experimental teaching of Medical Immunology as a platform to carry out practice of scientific research project-based experi-mental system among"5+3"integration students.By completing a mini-project research including experimental design-experimental operation-research article writing,students cultivated scientific research thinking and exercised scientific research practice ability,and generally reported that the course is very difficult,but after completing it,it is very rewarding.

Objective To compare the clinical effect between cannulated compression countersunk head screws(CS)and anatomical locking compression hook plate(LCP)for fractures of proximal fifth metatarsal bone at Lawrence zone Ⅰ.Methods A total of 60 patients with fractures of proximal fifth metatarsal bone at Lawrence zone Ⅰ from May 2021 to May 2023 were retrospectively analyzed.Of them,20 patients were treated by internal fixation with cannulated compression countersunk head screws(CS group),and other 40 patients were treated by internal fixation with anatomical locking compression hook plate(LCP group).The postoperative therapeutic effects were evaluated by using the Visual Analogue Scale(VAS)and the American Orthopaedic Foot and Ankle Society(AOFAS)Midfoot Scale.Incidences of postoperative complications were also recorded.Results The operations were successfully completed in all the 60 patients.The operation time in the CS group was shorter than that in the LCP group[37(15-74)min vs.50.5(28-102)min,P=0.002].The VAS score in the CS group immediately after surgery was lower than that in the LCP group[3(2-5)vs.4(2-5),P=0.004],and there was no significant difference between the two groups at 3,6,and 12 months after surgery and at the last follow-up(P＞0.05).At the 3rd month after operation,the AOFAS score in the CS group was better than that in the LCP group[52(23-62)vs.49(23-62),P=0.038],and there was no significant difference between the two groups at 6 and 12 months after surgery and at the last follow-up(P＞0.05).In the LCP group,there were 1 case of superficial wound infection,3 cases of long-term chronic pain,6 cases of foreign body sensation,5 cases of removal of the internal fixation by a second operation after one year postoperatively.In the CS group,there was only 1 case of foreign body sensation.Conclusions Both cannulated compression countersunk head screws and anatomical locking compression hook plate can effectively fix fractures of proximal fifth metatarsal bone at Lawrence zone Ⅰ.Compared with anatomical locking compression hook plate,cannulated compression countersunk head screws can shorten operation time,reduce postoperative pain,and facilitate early functional rehabilitation.

AIM To study the chemical constituents from the sticks and leaves of Croton cascarilloides Raeusch.and their biological activities.METHODS The 95％ethanol extract from the sticks and leaves of C.cascarilloides was isolated and purified by MCI,silica gel,Sephadex LH-20 and semi-preparative HPLC,then the structures of obtained compounds were identified by physicochemical properties and spectral data.LPS-induced NO RAW264.7 cell model induced by LPS was used to evaluate its anti-inflammatory activity in vitro.GES-1 injury model induced by taurocholic acid was used to screen the gastric mucosal protection activity.RESULTS Fourteen compounds were isolated and identified as bullatantriol(1),(-)-boscialin(2),(+)-dehydrovomifoliol(3),3-(hydroxylacetyl)-indole(4),pinoresinol(5),3,7-dimethyl-octa-1,7-diene-3,6-ol(6),(+)-syringaresinol(7),curcasinlignan B(8),cleomiscosin C(9),cleomiscosinD(10),2,6-dimethyl-octa-1,7-dien-3,6-diol(11),vanillin(12),vanillic acid(13),methyl vanillate(14).Compound 4 had certain anti-inflammatory activity,with IC50 values of 73.62 μmol/L.The protective rates of 25 μmol/L compounds 1-4,6,9-12 and 14 on gastric mucosal epithelial cells were 30.07％,34.18％,23.91％,30.92％,17.51％,19.69％,31.76％,22.46％,30.56％and 14.49％,respectively.CONCLUSION Compounds 1-14 are isolated from this plant for the first time.Compound 4 shows anti-inflammatory activity,1-4,6,9-12 and 14 show different degrees of gastric mucosal epithelial cell protective activity.

Objective:To observe effectiveness of combining diffusion tensor imaging (DTI) with motor evoked potentials (MEPs) in evaluating the upper limb motor functioning of stroke survivors.Methods:Thirty-seven stroke survivors with upper limb motor dysfunction were selected. At the 4th, 12th and 24th week after their onset, each was were assessed using Fugl-Meyer Upper Limb (FMA-UE) scoring, the National Institutes of Health stroke scale (NIHSS), the modified Rankin Scale (mRS), the Barthel Index (BI) and hemiplegic hand function classification. DTI was also applied and MEPs were measured. The patients were divided into an MEP positive group and an MEP negative group according to the existence of the MEP waveform. The DTI and MEP parameters were correlated with the FMA-UE scores, linear regressions were evaluated and a receiver operating characteristics curve was prepared to estimate the utility of DTI in predicting hand function. The sensitivity and specificity of MEPs in predicting hand function recovery were evaluated.Results:The asymmetry index (FAa) of the average anisotropy score of the posterior limb of the internal capsule and the FAa of the cerebral peduncle were both significantly correlated with the FMA-UE scores at the 12th and 24th weeks. The best cut-off points for predicting functional recovery of a patient′s hand were 0.155 for the FAa of the posterior limb of the internal capsule and 0.145 for the cerebral peduncle. Among the 37 patients, the MEPs of 8 (the MEP positive group) could be extracted, and their hand functions recovered completely. The sensitivity of the MEPs in predicting the complete recovery of hand function was 80% with 100% specificity. The linear regression analysis showed 77% prediction accuracy for the FAa and MEPs of the cerebral peduncle for upper limb motor function at the 24th week after onset. In the MEP negative group, two patients completely recovered their hand function, with one′s FAa less than 0.145, and the other′s more than 0.145. When the MEP was negative, the sensitivity of DTI in predicting the recovery of hand function was 50% with 81.5% specificity.Conclusions:DTI combined with MEPs can be used as an index to evaluate the prognosis of upper limb motor function in stroke patients.