BACKGROUND:Chronic tendinopathy is a tendon disorder extremely common in athletes and in the general population with repetitive strain injuries of tendons. The pathogenesis of tendinopathy remains unclear and hence treatment of tendinopathy is usual y pal iative.
OBJECTIVE:To investigate the of adipogenic and tenogenic ability of patel ar tendon-derived stem cel s isolated
from chronic tendinopathy and healthy rats in vitro.
METHODS:Tendon-derived stem cel s were isolated from patel ar tendons of chronic tendinopathy and healthy rats respectively. The tendon-derived stem cel s were cultured to the 3rd passage in complete culture medium, and cel morphology was observed. The cel s were divided into adipogenic induction group and control group. Cel s in the adipogenic induction group were cultured in adipogenic induction medium, while those in the control group cultured in complete culture medium. The ability of adipogenic differentiation between tendon-derived stem cel s isolated from the tendon of chronic tendinopathy and healthy rats in vitro was examined by oil red O staining and quantification assay. The mRNA expressions of C/EBPαand PPARγ2 were detected by real-time quantitative PCR. When 70%-80%cel s were confluent, the mRNA expressions of Col1a1, Scx, Tnmd and Dcn were also detected by real-time quantitative PCR.
RESULTS AND CONCLUSION:At the third passage, slender spindle-shaped cel s were seen in both two groups, but there was a little change in the cel morphology in the chronic tendinopathy group. Lipid droplets were formed after the cel s were cultured in adipogenic induction medium for 21 days. This was not observed in the control group. We observed more oil red O-positive oil droplets in tendon-derived stem cel s from the tendons of chronic tendinopathy rats than healthy rats. The difference between them was statistical y significant (P=0.004). The results of real-time quantitative PCR showed that the mRNA expressions of C/EBPαand PPARγ2 in the tendon-derived stem cel s from the tendons of chronic tendinopathy rats were significantly higher than those in tendon-derived stem cel s from the tendons of healthy rats (P=0.004);the mRNA expressions of Col1a1, Scx, Tnmd and Dcn in the tendon-derived stem cel s from the tendons of chronic tendinopathy rats were significantly lower than those in tendon-derived stem cel s from the tendons of healthy rats (P=0.009). In conclusion, tendon-derived stem cel s from chronic tendinopathy rats showed a higher ability of adipogenic differentiation, but a lower capacity of tenogenic differentiation compared to tendon-derived stem cel s from healthy rats, which might contribute to better understand the pathogenesis of tendinopathy.

BACKGROUND:Mesenchymal stem cells are commonly used in tissue engineering, while whether
synovium-derived mesenchymal stem cells from human knee joints can make a role in repair and regeneration of bone tissue as the appropriate seed cells need to be further verified.
OBJECTIVE:To study the osteogenic differentiation potential of synovium-derived mesenchymal stem cells which were harvested from human knee joint with end-stage osteoarthritis in vitro. Meanwhile, to identify the osteogenic characteristics of these induced synovium-derived mesenchymal stem cells.
METHODS:cellpopulations were enzymatical y released from the synovial membrane obtained from total knee arthroplasty. Nucleated cells were plated at an appropriate density (200 cells/cm2) for expansion at the maximum rate without colony-to-colony contact. Monoclone was obtained by selecting as primary synovium-derived mesenchymal stem cells. After primary cultured in control medium and expanded to three passages, synovium-derived mesenchymal stem cells were subjected to in vitro assays to investigate their osteogenesis potential in osteogenic medium containing dexamethasone,β-glycerophosphate and ascorbic acid.
RESULTS AND CONCLUSION:Nucleated cells from the synovial membrane formed single cel-derived colonies, which were of polygon shape and star shape, uniform in size. After three passages, homogeneous populations of fibroblast-like cells were observed. Under appropriate culture conditions, synovium-derived mesenchymal stem cells were induced to differentiate to the osteocyte lineages which had typical“slabstone”appearance of osteoblasts. Osteogenesis was stained positively for alkaline phosphatase staining at day 7 and formed mineralized nodular structures at day 21, which was confirmed by Alizarin red staining. Alkaline phosphatase activity assay showed a rise after the osteogenesis induction and reached the peak at day 7. Expressions of osteocyte specific genes, such as col agen type Ⅰ, Runx2, bone-binding protein and osteopontin, were al detected. These genes were expressed positively in osteogenic medium, and the mRNA expressions of col agen type Ⅰ, Runx2, bone-binding protein and osteopontin were enhanced significantly after 21 days. Our study demonstrates that synovium-derived mesenchymal stem cells isolated from knee joint of end-stage osteoarthritis patients could be induced into osteoblasts in vitro, and these induced cells have typical osteogenesis characteristics. Synovium-derived mesenchymal stem cells may play a role in the regenerative response during the process of bone injury, which are promising candidates for bone tissue engineering.

Objective:To investigate mechanisms underlying the signal crosstalk of VEGF-IL-6-STAT3 between cutaneous melanoma cells and vascular endothelial cells.Methods:EC-304 vascular endothelial cells were divided into 3 groups: control group cultured in conventional endothelial cell-conditioned medium, vascular endothelial growth factor (VEGF) group cultured in endothelial cell-conditioned medium containing 50 μg/L VEGF 165, A375 co-culture group co-cultured with a melanoma cell line A375. After 24-, 48- and 72-hour treatment, the culture medium was collected, and enzyme-linked immunosorbent assay was performed to detect the level of interleukin-6 (IL-6) . Cultured A375 cells were divided into 4 groups: control group receiving conventional culture in Dulbecco′s modified Eagle′s medium (DMEM) , A375+ EC-304 group co-cultured with EC-304 cells, A375+ EC-304+ IL-6 group co-cultured with EC-304 cells in DMEM containing 50 μg/L IL-6 (an agonist of the signal transducer and activator of transcription-3 [STAT3] pathway) , A375+ EC-304+ JSI-124 group co-cultured with EC-304 cells in DMEM containing 1 μmol/L JSI-124 (a STAT3 pathway inhibitor) . After 24-, 48- and 72-hour treatment, cells were collected, and Western blot analysis, cell counting kit-8 (CCK8) assay and Transwell invasion assay were performed to determine the protein expression of STAT3 and phosphorylated (p) -STAT3, cellular proliferative activity and invasive activity, respectively. Two-way analysis of variance and t test were used for statistical analysis. Results:The level of IL-6 significantly increased in the culture medium of EC-304 cells in the VEGF group and A375 co-culture group compared with the control group ( FVEGF = 29.63, P < 0.001; FA375 = 11.09, P = 0.020) . Compared with the control group, the A375+ EC-304 group showed significantly enhanced protein expression of p-STAT3 in A375 cells ( P < 0.001) , increased cell activity ( P < 0.001) , and increased number of invasive cells (152.66 ± 16.04 vs. 86.13 ± 7.24, t= 4.43, P < 0.001) ; compared with the A375+ EC-304 group, the A375+ EC-304+ IL-6 group showed significantly increased protein expression of p-STAT3 ( P < 0.001) , enhanced cell activity ( P < 0.001) , and increased number of invasive cells (187.34 ± 14.38, t= 2.17, P < 0.001) ; compared with the A375+ EC-304 group, the A375+ EC-304+ JSI-124 group showed significantly decreased protein expression of p-STAT3 ( P < 0.001) , decreased cell activity ( P < 0.001) , and decreased number of invasive cells (124.92 ± 8.72, t=-1.86, P < 0.001) . Conclusion:There is a signal crosstalk of VEGF-IL-6-STAT3 between cutaneous melanoma cells and vascular endothelial cells, which may play an important role in the proliferation and invasion of A375 cells.

OBJECTIVE To study the antidepressant effects of ammoxetine(AMX)and the underlying mechanisms. METHODS Two behavioral despair models,the tail suspension test (TST) and the forced swimming test(FST),were used to evaluate the antidepressant-like effects of AMX 2.5-20 mg · kg-1 following oral administration. Monoamine neurotransmitter p-chloro-phenylalanine(p-CPA)andα-methyl-p-tyrosine(AMPT) depletion models in mice were used to investigate the effects of AMX on levels of 5-serotomin(5-HT)and norepinephrine(NE)in the brain. RESULLTS The results of behavioral study showed that compared with normal control group,AMX(10 and 20 mg · kg-1)reduced the immobility time of mice by 51.4% and 80.7% in the TST(P<0.05,P<0.01) or by 48.0% and 66.2% in the FST (P<0.05),respectively. Locomotion activity test indicated that AMX did not increase or decrease the movement distance of mice,demonstrating that AMX had no excitatory or inhibitory actions on the central nervous system. Moreover,AMX(5,10 and 20 mg·kg-1)exerted antidepressant effects in the p-CPA induced 5-HT depletion model and AMPT induced NE depletion model,as evidenced by the significantly reduced immobility time,ie,63.9%,93.4%,90.5% and 61.9%,77.2%,100% reduction in the TST (P<0.01),respectively,and AMX at the dose of 20 mg·kg-1 significantly increased the concentrations of 5-HT and NE by 144.7% and 57.2% in the mouse brain(P<0.05) ,respectively. CONCLUSION AMX has strong antidepressant-like effects in behavioral despair models and monoamine neurotransmitter depletion models in mice,which is involved in the increased levels of 5-HT and NE in the brain.

OBJECTIVE Toexploretheantidepressanteffectsofalbiflorinandtheinvolvementof hypothalamic-pituitary-adrenocortical (HPA) axis function in its antidepressant potency.METHODS Two weeks after the olfactory bulbectomized (OB)surgery,albiflorin (2.5 ,5.0 ,10.0 mg·kg -1 ,ig) and imipramine 5.0 mg·kg -1 (ig)were given to rats twice a day for 14 d.The open-field test was con-ducted to evaluate the move ment distance,move ment ti me and velocity of olfactory bulbecto mized rats and sham-operated rats.The serum levels of corticosterone(CORT)and adrenocorticotropic hormone (ACTH)in rats were measured by the enzyme linked immunosorbent assay.The expression levels of glucocorticoids receptor (GR)in the hippocampus of the rats were analyzed using Western blot proce-dures.RESULTS Comparedwithsham-operatedrats,movementdistance,movementtimeandveloci-ty of the OB rats were significantly increased (P<0.01 ).Albiflorin 1 0.0 mg·kg -1 significantly reduced the movement distance,movement time and velocity of OB rats (P<0.05)after being given for 7 d. The movement properties were significantly reduced by albiflorin 5.0 and 10.0 mg·kg -1 when given for 14 d (P<0.05).The OB rats demonstrated significantly increased levels of serum CORT and ACTH (P<0.01 )and decreased GR expression in the hippocampus (P<0.01 ).Albiflorin 2.5,5.0 and 10.0 mg·kg -1 significantly reduced the serum CORT and ACTH levels (P<0.05),while albiflorin 5.0 and10.0mg·kg-1increasedtheexpressionofhippocampalGR(P<0.05).CONCLUSION Albiflorin may have re markable behavioral antidepressant effects on olfactory rats and one of the related mecha-nis ms may be its regulation of the hyperactivity of HPA axis function.

BACKGROUND:Currently, cellular composition and the features of the nucleus pulposus are stil not to be clarified.
OBJECTIVE:To establish the in vitro culture system of rat nucleus pulposus-derived mesenchymal stem cells and to identify their multi-lineage differentiation potential.
METHODS:Mesenchymal stem cells from the nucleus pulposus tissues of Sprague-Dawley rats were cultured in vitro. Then, cells at passage 3 were induced to differentiate into osteoblasts, adipocytes and chondrocytes as experimental group. cells cultured with basic culture medium served as controls.
RESULTS AND CONCLUSION:cells isolated from rat nucleus pulposus could form the sunflower-like colonies and exhibit clone-like growth when they cultured at a low density. cells at passage 3 became homogeneous and exhibited fibroblast-like morphology. After 28 days of osteogenic induction, arizarin red positive signals were detected in the experimental group. The mRNA expressions of RunX2, osteopontin and osteocalcin were significantly increased in the experimental group, compared to the control group (P<0.05). After 21 days of adipogenic induction, oil red-O positive cells were detected in the experimental group. The mRNA expressions of C/EBPαand PPARγ2 were significantly increased in the experimental group, compared to the control group (P<0.05). After 21 days of chondrogenic induction, safranin O/fast green staining was positive in the experimental group. The mRNA expressions of aggrecan and Col2a1 were significantly increased in the experimental group, compared to the control group (P<0.05). Our findings in this study suggested that nucleus pulposus-derived mesenchymal stem cells could be isolated from the Sprague-Dawley rat nucleus pulposus and exhibited clonal-like growth when they were cultured in vitro. These cells were confirmed to have the potential to differentiate into adipocytes, osteoblasts and chondrocytes in vitro.

Objective To investigate the surgical methods and short-term effects of Internal-braceTM technology combined with modified Brostrom procedure for treatment of chronic ankle instability.Methods A retrospective case series study was made on 17 patients with chronic ankle instability treated using the Internal-braceTM technology combined with modified Brostrom procedure from May 2015 to April 2016.There were 10 males and 7 females,at age of 24 and 36 years (mean,31.8 years).A left ankle injury occurred in 6 patients and a right ankle injury in 11 patients.Operation time,postoperative complications and incision healing was documented after operation.Ankle stability was tested using the anterior drawer test and lateral stress test,and ankle range of motion was detected.American orthopedic foot and ankle society (AOFAS) score was used for postoperative efficacy evaluation.Results Operation time was 45 to 84 minutes (mean,64.5 minutes).None of the patients revealed neurological deficits after operation.All incisions healed by the first intension.Full weight bearing was started two weeks after operation.All patients were followed up for mean 3.5 months (range,1-6 months).At the final follow-up,both anterior drawer test and lateral stress test were negative.All patients had a normal range of motion of the ankle after operation.AOFAS score was increased from preoperative (36.2 ± 13.4)points to (91.2 ± 6.7) points at the final follow-up (P ＜ 0.01).According to the AOFAS score,the results were excellent in 15 patients and good in 2 patients,with the good rate of 100％.Conclusion For chronic ankle instability,Internal-braceTM technology comnbined with modified Brostrom procedure benefits wound healing and functional recovery,reduces incidence of complications and exhibits satisfactory short-term outcome.

Aim To investigate the effect of the total flaconoids extracted from Xiaobuxin-Tan g ( XBXT-2 )
on the hyperactivity of hypothalamic-pituitary-adrenal axis in mouse learned helplessness model. Methods Learned helplessness was induced by inescapable foot shock stress over 1h session for 5 days. After screen-ing, we divided learned helplessness mice into five groups:IS, inescapable shock;Dlx, dulxetine(20 mg ·kg-1);XBXT-2(25,50 mg·kg-1). Latency to es-cape shocks and escape failure had been recorded. During the test, Dlx(20 mg·kg-1 ) and XBXT-2(25, 50 mg·kg-1 ) were administered intragastrically once daily for four days. Serum corticosterone level and ad-renocorticotropic hormone ( ACTH ) level were meas-ured by ELISA, and expression of glucocorticoids re-ceptor ( GR) α/β and brain-derived neurotrophic fac-tor ( BDNF ) in hippocampus was determined using Western blot method. Results XBXT-2 (25,50 mg·
kg-1 ) or duloxetine treatment showed antidepressant effect in mouse learned helplessness model, as demon-strated by the decreased escape failure and escape la-tency. Our ELISA results showed that XBXT-2 or du-loxetine significantly decreased serum corticosterone level and its upstream stress hormone ACTH level in learned helplessness mice. Furthermore, Western blot result demonstrated XBXT-2 treatment increased GRs and BDNF expression in hippocampus. Conclusions XBXT-2 produces significant antidepressant effect on learned helplessness mice. In addition, the modulation of HPA axis produced by XBXT-2 may be important mechanism underlying its antidepressant-like effect in mouse learned helplessness model.

Objective:To study the application value of practical demonstration of actual X-ray film images in the experimental teaching of radiography technology courses in medical imaging undergraduates.Methods:A total of 63 medical imaging undergraduates of Grade 2015 were randomly divided into three groups to receive part of the experimental courses about chest and abdomen radiography examination. Their pre-class work and machine were the same. As the experimental group, group A and group B added demonstration with X ray film images, while group C (control group) did not. The different teaching effects of the two methods were evaluated by simulate practical assessment and quiz. The accepting degree of demonstration method was evaluated in accordance with questionnaire survey.Results:The scores of simulated practical assessment (7.36±1.39) and quiz (4.24±2.01) in experimental group were significantly higher than those of (6.05±1.28) and (3.10±1.48) in the control group, with a statistically significant difference ( P<0.01, P=0.024). Questionnaire survey showed that the experimental group were 100% accepted practical demonstration of X ray film images. Conclusion:The application of practical demonstration of X-ray film images in radiology technology experimental courses can help undergraduates to accept new knowledge, deepen impression on knowledge and improve teaching effect, which is worth developing and popularizing.

Objective: To examine the association of 24 hour movement behaviors with emotional and behavioral problems among left behind children, so as to provide a theoretical reference for the practice of 24 hour activity interventions to promote emotional and behavioral problems in this population. Methods: From February to May 2023, 1 117 left behind children in grades 4-6 from 10 primary schools in five cities in Zhejiang Province were selected using a convenient cluster sampling method to conduct a questionnaire survey examining 24 hour movement behaviors, as well as emotional and behavioral problems. The general linear model was adopted to analyze the association between satisfying the 24 hour movement behavior guidelines, and emotional and behavioral problems among left behind children. Results: The sleep duration compliance rate was the highest (52.19%), while the moderate-to-vigorous PA (MVPA) compliance rate was the lowest (17.73%). The compliance rate of the three activities accounted for 7.43 %. There was a dose response between the number of guidelines satisfied, and the emotional and behavior of left behind children; that was, satisfaction of a higher number of guidelines was associated with a lower risk of emotional and behavioral problems among left behind children (difficulty factor: β=-0.56, 95%CI =-1.23--0.19; strength factor: β=0.50, 95%CI =-0.48-1.22, P < 0.01). Compared to satisfying none of the guidelines, satisfying the guidelines for screen time ( β=-0.23, 95%CI =-2.18- -0.14 ) and sleep duration ( β=-0.13, 95%CI =-1.66--0.11) was negatively correlated with the difficulty factor, while satisfying the guideline for MVPA ( β=0.13, 95%CI =0.09-1.08) and sleep duration ( β=0.18, 95%CI =0.09-1.40) was positively associated with the strength factor. In addition, satisfying two or all three of the guidelines was more strongly associated with these outcomes than satisfying one of the recommendations ( P <0.01). Conclusions Meeting the 24 hour movement behavior guidelines can improve emotional and behavioral problems among left behind children. It is necessary to raise their awareness of the effect of satisfying the 24 hour movement behavior guidelines and formulate comprehensive intervention measures.