Single-Cell RNA Sequencing of Bone Marrow Mesenchymal Stem Cells from the Elderly People

Background and Objectives@#Bone marrow mesenchymal stem cells (BMSCs) show considerable promise in regenerative medicine. Many studies demonstrated that BMSCs cultured in vitro were highly heterogeneous and composed of diverse cell subpopulations, which may be the basis of their multiple biological characteristics. However, the exact cell subpopulations that make up BMSCs are still unknown. @*Methods@#and Results: In this study, we used single-cell RNA sequencing (scRNA-Seq) to divide 6,514 BMSCs into three clusters. The number and corresponding proportion of cells in clusters 1 to 3 were 3,766 (57.81%), 1,720 (26.40%), and 1,028 (15.78%). The gene expression profile and function of the cells in the same cluster were similar. The vast majority of cells expressed the markers defining BMSCs by flow cytometry and gene expression analysis. Each cluster had at least 20 differentially expressed genes (DEGs). We conducted Gene Ontology enrichment analysis on the top 20 DEGs of each cluster and found that the three clusters had different functions, which were related to self-renewal, multilineage differentiation and cytokine secretion, respectively. In addition, the function of the top 20 DEGs of each cluster was checked by the National Center for Biotechnology Information gene database to further verify our hypothesis. @*Conclusions@#This study indicated that scRNA-Seq can be used to divide BMSCs into different subpopulations, demon-strating the heterogeneity of BMSCs.

Application of ultrasound-guided thoracic paravertebral nerve block in percutaneous kyphoplasty / 中华全科医师杂志

From January 2016 to June 2017, 68 patients with thoracic osteoporotic compression fractures were treated with percutaneous kyphoplasty, including 31 cases with ultrasound-guided thoracic paravertebral nerve block (group A) and 37 cases with local anesthesia (group B). The duration of analgesia in group A was longer than that in group B (P<0.05). The satisfaction of anesthesia in group A was higher than that in group B (90% vs. 68%, P<0.05). There was no significant difference in length of hospital stay and cost between the two groups (P>0.05). The post-operative VAS scores was significantly lower than those of pre-operation in both groups (P<0.05). The intraoperative VAS score of group A was lower than that of group B (P<0.05). There was no significant difference between the two groups in mean arterial pressure and heart rate (P>0.05). No cardiovascular and cerebrovascular adverse reactions occurred in both groups. Ultrasound-guided thoracic paravertebral nerve block is a safe and effective method used in percutaneous kyphoplasty.

Electrical stimulation of the pelvic floor combined with bladder training for treating urinary dysfunction after incomplete spinal cord injury / 中华物理医学与康复杂志

Objective To evaluate the effect of electrical stimulation of the pelvic floor muscles combined with bladder training on urinary dysfunctionafter incomplete spinal cord injury.Methods Sixty-two incomplete spinal cord injury patients who had received an operation between November 2009 and December 2014 were enrolled and divided randomly into a control group (n=32) and a treatment group (n =30).Both groups were treated with conventional intermittent catheterization,while the treatment group was additionally given electrical stimulation of the pelvic floor muscles combined with bladder training.The residual urine volume was recorded before and after the treatment.Uurodynamic examinations were conducted,and the rate of successful catheter extraction and of urinary tract infection on the 15th and 30th day of treatment,were recorded and analyzed.Results All of the patients were followed-up for an average of 18.5 months.Significant improvement was observed in the residual urine volume,the maximum or average urinary flow rate,and the detrusor pressure at peak flow of both groups.However,at the end of follow-up the treatment group recorded significantly better results on all these measures than the control group.The successful catheter extraction rate of the treatment group (96.7％) was significantly higher than that of the control group and their average number of catheterization days was significantly fewer.The urinary tract infection rates on the 15th and 30th day of treatment were 16.7％ and 6.7％ in the treatment group,significantly lower than in the control group.Conclusions Electrical stimulation of the pelvic floor combined with bladder training significantly improves urination function after an operation for incomplete spinal cord injury,decreases the days of catheterization and lowers the rate of urinary tract infection.Such combined therapy is worth promoting in clinical practice.

Anatomy of the attachment of the medial patellofemoral ligament of human knee / 解剖学报

ObjectiveTo study the anatomic characteristic of the attachment of medial patellofemoral ligament and its function in patellar stability. MethodsThirty adult cadaver knees were used for anatomic study, and the attachments of medial patellofemoral ligament were observed and measured. Results The femoral attachment of medial patellofemoral ligament was anchored to the bone between the medial femoral epicondyle and the adductor tubercle. The fibers here were thin and narrow, and became thick and wide to the anterior. The patellar attachment was in the superior two-thirds of the medial margin of the patella. The fiber here were the thickest and the widest. Conclusion The anatomic characteristic of the attachment of medial patellofemoral ligament was revealed, providing anatomical bases for surgery.

Accuracy of "funnel technique" in the thoracic pedicle screw instrumentation: experimental and clinical study / 中华创伤杂志

Objective To evaluate the accuracy of thoracic pedicle screw placement using the "funnel technique" and investigate its consistency in experimental study and clinical application.Methods The clinical data of three human cadavers and 11 patients with the installation of at least one thoracic pedicle screw at T1 -T12 from August 2006 to July 2008 were retrospectively analyzed. One junior spine surgeon lack of experience were responsible for placing these screws with the "funnel technique".The accuracy of screw placement and the complications related to the use of thoracic pedicle screws were analyzed by assessing postoperative CT scans. Results The mean follow-up time was 23.1 months,which showed no vascular or visceral complications, or iatrogenic neurological injury. The rate of unintended cortex perforations was 14% (10/72) in cadavers and 15% (8/55) in patients, respectively.The critical perforation occurred in two screws (3%) in cadavers and one screw (2%) in patients. There was no statistical difference between the percentage of cortex perforations in cadavers and patients. Of all the 11 patients, screw violation occurred laterally in six ( 11% ), medially in one ( 2% ) and superiorly in one (2%). No violations occurred inferiorly or anteriorly. For all patients, only one screw needed revision. The perforations made by the junior spine surgeon occurred in six screws in the first cadaver, three in the second cadaver and one in the third cadaver. Conclusions The "funnel technique" is a simple,safe, accurate and cost-effective technique for pedicle screw placement. The result of the experimental study is consistent with that of the clinical application. "funnel technique" is helpful for junior spine surgeons to master the technique of thoracic pedicle screw placement.

Anatomical study of the femoral and tibial insertions of the anterolateral and posteromedial bundles of human posterior cruciate ligament / 解剖学报

Objective To provide an anatomic evidence for the double-bundle posterior cruciate ligament (PCL) reconstruction, the sizes and locations of the attachments of the PCL to the tibia and the femur were measured. Methods We studied 30 cadaveric knees. PCLs were divided into anterolateral and posteromedial bundles to the insertion footprint, and those locations were measured and described. Results The distances from the center of the femoral insertions of the anterolateral and posteromedial bundles to the anterior margin of the medial femoral condyle were (8.52±1.81)mm and (11.63±1.81)mm. The vertical distances from the center of the femoral insertions of the double-bundle to the intercondylar roof were (4.67±0.55)mm and (10.32±1.23) mm. The vertical distances from the tibial insertion of the center of the double-bundle to the plane of the tibial articular surface were (8.43±1.21)mm and (14.52±2.31)mm. The distances from the medial margin of the articular cartilage of the tibial plateau to the center of the tibial insertions of double-bundle were (47.44±6.23)mm and (45.95±6.32)mm. The areas of the insertions of the anterolateral and posteromedial bundles on the femur were (107.12±15.25)mm~2 and (65.35±10.27)mm~2. The areas of the insertions of the double-bundle on the tibia were (50.07±11.33)mm~2and (51.08±10.22)mm~2. Conclusion The anatomic characteristic of the attachment of the anterolateral and posteromedial bundles was revealed, providing anatomical bases for surgery.

Isometry of grafts in PCL reconstruction under femoral tunnel shifting condition / 医用生物力学

Objective To explore the isometry of grafts in PCL(posterior cruciate ligament)double-bundle re-construction under femoral tunnel shifting condition.Method Knee specimens from ten fresh frozen cadavers were used.PCL were divided into anterolateral bundles(ALB)and posteromedial bundles(PMB)to the inser-tion footorint.The anterior,postedor,proximal,distal and central points of the two bundles'femoral attachment site were respectivelyanchored to the middle of the PCL's tibial attachment site by the trial wires.Changes in length of the intra-articular part of the wires were recorded while the knee was flexed from 0°to 120°.Result The length changes in every point were compared.All of the maximal length changes of ALB's proximal,pos-todor points and PMB's proximal points were not greater than 2mm.No significant difference between the length changes of ALB's proximal point and posterior(P=0.864>0.05)was found.Conclusions The femo-ral tunnel for the PCL double-bundle reconstruction should be located as follows:ALB should be at the middle point of upper edge of femoral attachment site(proximal point),while PIVIB at the middle point of femoral attachment site(proximal point).