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BACKGROUND: As a unique structure of the cervical spine, the occurrence, development and progression of the uncovertebral joint directly affect the stability and range of motion of the cervical spine, and are also closely related to the pathogenesis of cervical spondylosis. A thorough understanding of the developmental characteristics of the uncovertebral joint is of great significance for the pathogenesis, diagnosis, and treatment of cervical spondylosis. OBJECTIVE: By using imaging and three-dimensional reconstruction technology to measure and observe the cervical uncinate process-related angle in a large sample of different age groups, the aim is to reveal the characteristics of its changes with age and vertebral growth, as well as its relationship with cervical spine stability. METHODS: Using a retrospective research design, we collected 1 447 cases of raw CT imaging data that meet the study requirements for complete cervical spine segments. The raw data were imported into Mimics 21.0 software in DICOM format for post-processing and measurement of angle of uncinate process and sagittal angle of uncinate process. The data were grouped based on gender, age, and side. RESULTS AND CONCLUSION: (1) With the increase of vertebral sequence, the angle of uncinate process increased in a V-shaped shape, and the lowest peak was at C5. The overall population showed a sharp peak with the increase of age, and the peak value mostly occurred in the age range of 30-39 years. (2) The sagittal angle of the uncinate process increased like a fishhook with the increase of the vertebral sequence, and the overall angle of the uncinate process increased with age, and the peak value mostly occurred in the age range of 20-29 years. The uncinate process angle and sagittal angle showed only partial significant differences between sides and genders (P < 0.05). (3) It is concluded that the angle of the uncinate process increased with the increase of vertebral sequence in a V-shaped manner. The sagittal angle of the uncinate process increases like a fish hook with increasing vertebral order, while the two angles generally peak with increasing age. The angle of the uncinate process is about 131°, which may be closely related to the stability of the cervical spine, while the sagittal angle of the uncinate process is about 14°, and its function may play a certain role in limiting the excessive rotation of the cervical spine. [ABSTRACT FROM AUTHOR]

BACKGROUND: The motion of the knee joint is a three-dimensional motion with three translational degrees of freedom and three rotational degrees of freedom. When the prosthesis is implanted in total knee arthroplasty, the varus angle of the coronal plane, the anteroposterior angle of the sagittal plane and the rotation angle of the axial plane should be fully considered. OBJECTIVE: To summarize the clinical advantages and disadvantages of femoral and tibial prosthesis implantation angle in total knee arthroplasty, so as to provide reference for effective prosthesis implantation in total knee arthroplasty. METHODS: The first author searched the literature on prosthesis implantation in PubMed database and CNKI database by computer. The English key words were “total knee arthroplasty, total knee replacement, femoral, tibial, coronal, sagittal, axial, prosthesis, component, alignment, osteotomy”. The Chinese key words were “total knee arthroplasty, femur, tibia, prosthesis, osteotomy, coronal, sagittal, axial, alignment”. The articles that meet the search terms are preliminarily screened, and the relevant articles related to the review content and the clinical advantages and disadvantages of prosthesis implantation are retained for further detailed analysis, induction and summary. RESULTS AND CONCLUSION: (1) On the coronal plane of the femur, the angle between the mechanical axis of the lower limb and the anatomical axis of the femur is measured through the full-length film of the weight-bearing position of the lower limb as a reference for femoral osteotomy. The 4-6° valgus osteotomy is often taken, and the prosthesis is implanted perpendicular to the mechanical axis. (2) In the sagittal plane of the femur, to obtain good knee flexion function, the 0-3°anteversion osteotomy is often taken and the prosthesis is implanted slightly anteversion. (3) In the axial plane of the femur, although surgical transepicondylar axis is regarded as the rotation center of the distal femur, it is more convenient to refer to posterior condylar axis when using surgical instruments, and the prosthesis is rotated 2-5° outward relative to posterior condylar axis. (4) In the coronal plane of the tibia, to obtain the rectangular space and horizontal joint line in the extended position, the prosthesis should be implanted perpendicular to the mechanical axis of the tibia. (5) In the sagittal plane of the tibia, the polyethylene gasket has a certain retroversion angle, and the prosthesis is often implanted with a retroversion of 0-7°. (6) In the axial plane of the tibia, because the Akagi line is approximately parallel to the anterior and posterior axis of the tibia, the anterior and posterior axis of the prosthesis is often implanted parallel to the Akagi line. [ABSTRACT FROM AUTHOR]

BACKGROUND: The changes of temporal-mandibular join before and after compensatory correction about Angle class III malocclusion are rarely reported.OBJECTIVE: To investigate the changes of osseous structure about temporal-mandibular joint pre/post-treatment for Angle III malocclusion through cone-beam CT(CBCT).METHODS: The study was in accordance with the ethical requirements of School of Stomatology of Tianjin Medical University. Thirty eligible Han patients with Angle class III malocclusion were enrolled, with the age of(16.5±2.6) years. All patients and their guardians signed the informed consents. The patients were treated by fixed appliance and class III traction and rocking-chair archwire. CBCT was conducted before and after treatment. CBCT data were measured and analyzed with the reconstructing image for comparing the glenoid morphology, condylar morphology, condylar axial and condylar growth.RESULTS AND CONCLUSION:(1) The joint nodules angle, condylar sagittal angle, articular fossa depth and condylar macroaxis angle were increased, the upper part of condyle was reduced and condylar process moved rearwards in patients with Angle III malocclusion after treatment(P < 0.05).(2) The difference of condylar minor axis and condylar inclination angle on coronal plane had no significant difference(P > 0.05), but condylar minor axis had increased tendency and condylar inclination angle on axial surface had decreased tendency.(3) To conclude, the morphology of temporal-mandibular joint in patients with class III malocclusion Angle pre/post-treatment is different to some extent. [ABSTRACT FROM AUTHOR]

BACKGROUND: An orthodontist can gain all comprehensive data about the tooth and jaw based on a model measurement. With the development of CAD/CAM, a three-dimensional (3D) digital model shows more accurate information than a traditional model. OBJECTIVE: To explore the characteristics of dental arch and basal bone in permanent dentition Angle Class II malocclusion based on 3D digital models. METHODS: Thirty cases of normal occlusionin permanent dentition were selected as control group, and 30 cases of Angel II1 and 30 cases of Angel II2 malocclusion were enrolled, respectively. Three kinds of 3D digital models were established using a 3shape R700 scanner and measured with Orthoanalyzer 2013. The data of individual normal occlusion and Angel II1 and Angel II2 data were analyzed statistically with SPSS 19.0 software respectively. Intergroup comparison was analyzed by the least significant difference test method. RESULTS AND CONCLUSION: Maxillary and mandibular dental arch length and maxillary dental arch width of front section (3-3) and middle section (4-4)/maxillary basal bone length and mandibular basal bone width of middle section (4-4): II2 > normal occlusion > II1 (P < 0.05). Mandibular dental arch front width of section (3-3)/maxillary and mandibular basal bone length: normal occlusion > II1> II2 (P < 0.05). Maxillary dental arch width of behind section (6-6)/maxillary basal bone width of front section (3-3) and middle section (4-4)/mandibular basal bone width of front section (3-3): normal occlusion > II2 > II1 (P < 0.05). The angle of tooth long axis and plane: there was significant difference in the Angel II1, II2 and normal occlusion (P < 0.05). Maxillary posterior-teeth area (coronary): II1 > II2 > normal occlusion (P < 0.05). Mandibular posterior-teeth area (coronary): II2 > normal occlusion > II1 (P < 0.05). The dental arch of Angel II1 was narrow and long in shpape, and the dental arch of Angel II2 was wide and short in shape. Sagittal discordant existed in the anterior of Angel II1, such as lip-side incline of maxilla and mandible. Coronal discordant existed in the median and posteior of Angel II1, such as palatine-side incline of the maxillary dental arch, and buccal-side incline of the mandible. Sagittal discordant existed in the anterior of Angel II2, e.g. lingual-side incline of the maxilla and mandible. No discordant existed in the posterior section of Angel II2. [ABSTRACT FROM AUTHOR]

BACKGROUND: As a unique structure of cervical vertebra, the occurrence and development of uncinate joint are closely related to the stability and range of motion of cervical vertebra, but it is also closely related to the incidence of cervical spondylosis. Understanding the developmental characteristics of uncinate joint is of great significance to the type, diagnosis and treatment of cervical spondylosis. OBJECTIVE: To find the changing rules of uncinate process with age and increasing vertebral order by measuring the related diameters of uncinate process in cervical uncinate joints of different ages. METHODS: In a retrospective study, the imaging data of 1 447 cases of cervical vertebrae of different ages were collected. According to the age, they were divided into < 10 years, 10-19 years, 20-29 years, 30-39 years, 40-49 years, 50-59 years, ≥ 60 years groups. The uncinate process length, width, height, uncinate-transverse distance, uncinate process distance, anterior foot distance and posterior foot distance of uncinate process were measured. RESULTS AND CONCLUSION: (1) The results showed that there were differences between males and females in the related structure of uncinate process, and the length, height and width of uncinate process increased slowly with the increase of vertebral sequence and age. The distance between uncinate process, the distance between the front foot of uncinate process and the distance between the posterior foot of uncinate process increased slowly with the increase of vertebral sequence, but the distance between them did not change significantly with the increase of age. The distance between hook and transverse increased slowly with the increase of vertebral order, but the change with age was not significant. (2) These results have concluded that there are gender and lateral differences in the uncinate process related structure of the uncinate joint of the cervical vertebra, and the overall trend increases slowly with the increase of age and vertebral order. Mastering the aging characteristics and development law of the uncinate joint can provide a theoretical basis for the prevention, diagnosis and treatment of related cervical spondylosis. [ABSTRACT FROM AUTHOR]

BACKGROUND: Lesions of structures around the ventral side of the brainstem are located in the deep surface of the craniocervical junction, surrounded by important structures. The far lateral approach is the basic surgical method, but sex and lateral differences should be considered in the approach. OBJECTIVE: To analyze the morphological characteristics of the foramen magnum and occipital condyle by three-dimensional reconstruction measurements, thereby providing anatomical parameters for the far lateral approach to the skull base in clinical practice. METHODS: A total of 673 adult patients (448 males and 225 females) with head and neck CT scans were selected. The age ranged from 20 to 87. The length and width of the foramen magnum were measured. The area and index of the foramen magnum were then calculated by formulas. The length and width of the occipital condyle were measured, as well as the angle between the long and sagittal axis of the occipital condyle (O-S angle), the angle between the line connecting the midpoints of anterior and posterior foramen magnum and the line connecting the midpoint of anterior foramen magnum and the intersection of posterior occipital condyle and lateral foramen magnum (F-O angle), and the angle between the line connecting the midpoints of anterior and posterior foramen magnum and the line connecting the midpoint of anterior foramen magnum and the midpoint of the posterior wall of the hypoglossal canal (F-H angle). The sex and lateral differences of each index were analyzed. RESULTS AND CONCLUSION: There were statistical differences in foramen magnum indexes except between sexes (P > 0.05). The indexes of occipital condyle were significantly higher in males than in females (P < 0.05) except that the left occipital condyle width in males was lower than that in females (P > 0.05). The O-S angle in males was smaller than that in females, and there was a significant difference in the left O-S angle between sexes (P < 0.05). There was no statistical difference between right and left F-H angles. Significant differences were observed in occipital condyle length, occipital condyle width, O-S angle, and F-O angle (P < 0.05). These findings indicate that the parameters of the foramen magnum and occipital condyle were different in sex and on both sides. For the far lateral and transcondylar approaches, the right approach was relatively safe and exposed to a larger range. The length, width, and area of the foramen magnum, the length of the occipital condyle, and O-S angle in males were larger than those in females. Therefore, the sex difference should be considered in the far lateral approach. [ABSTRACT FROM AUTHOR]

BACKGROUND: Uncinate processes hyperplasia often leads to cervical spondylosis. Uncinate process resection without internal fixation is of great significance, but there are still many problems. OBJECTIVE: To establish a three-dimensional finite element model of the whole cervical vertebrae (C0-T1), and to explore the characteristics and laws of stress change after excising different ranges of the uncinate process, so as to provide a theoretical basis for the surgical treatment of clinical cervical spondylosis. METHODS: Raw data were obtained from spiral CT thin-section scans of 40-year-old male normal adult volunteers. Mimics, GeomagicStudio, Hypermesh, Abaqus and other software technologies were used to establish (C0-T1) full cervical three-dimensional finite element model. Models of 50% unilateral uncinate processes excision, 100% unilateral uncinate processes excision and 100% bilateral uncinate processes excision were constructed on the C5 vertebral body. After loading the same torque, six working conditions of flexion, extension, lateral flexion and rotation were assigned to observe changes of stress and displacement of the cervical facet joint in different states after the resection of the uncinate process. RESULTS AND CONCLUSION: (1) By constructing the finite element model of the normal cervical vertebrae and the uncinate process in different ranges, after loading the same torque, the stress concentration area of the cervical articular process was now moved up from C6 in the normal group to C5 in the different ranges of uncinate process excision groups. The stress of the nodal process increased with the increase of the vertebral sequence. (2) The stress concentration areas were located at C5 and C6, and the overall shape was sharp. The degree of resection of the uncinate process reduced the stability of the cervical spine, and the degree of reduction increased with the extent of resection. [ABSTRACT FROM AUTHOR]

BACKGROUND: There is a high similarity of the cervical vertebrae between rhesus monkeys and human, both in terms of the number of cervical vertebrae and the anatomical structure of cervical vertebrae, especially the uncinate joints, which are unique to the cervical vertebrae, so they can be used as an ideal animal experimental model. However, there are few reports on the mechanical comparative study between the two. OBJECTIVE: To establish the finite element model of adult human cervical vertebra and adult rhesus monkey cervical vertebra, to compare the characteristics of stress and displacement of the uncinate joint between human and rhesus monkey cervical vertebra under six working conditions by means of finite element analysis, and to provide theoretical basis for clinical vertebral replacement. METHODS: A 40-year-old adult volunteer and a 7-year-old adult male rhesus monkey were scanned by spiral CT. The original cervical vertebra CT data were introduced into Mimics 21.0 to establish a preliminary three-dimensional model. Through the optimization, assignment, assembly and other tissue grids of each segment of cervical vertebra, intervertebral disc, ligament and so on, the cervical vertebra finite element model was constructed by Abaqus, and 75 N additional load and 1 N·m external force couple moment were loaded on the model. Comparative mechanical analysis was carried out under six working conditions of flexion, extension, lateral area and rotation, in order to find the mechanical change trend and difference between them. RESULTS AND CONCLUSION: (1) Both human and rhesus monkey cervical vertebrae had the unique structure of uncinate joint of cervical vertebrae. Through finite element modeling, the stress and displacement changes of the uncinate joint between them were basically consistent, and the stress and displacement concentration points were all at C5. There was a significant difference between them. (2) However, the cervical vertebra of rhesus monkey can be used as the best candidate animal for clinical cervical vertebra animal model, and provide theoretical basis for artificial cervical vertebra replacement [ABSTRACT FROM AUTHOR]

BACKGROUND: Epidermal growth factor receptor is a key factor regulating the cell cycle and its downstream signaling pathway is widely involved in the regulation of various biological processes of cells. OBJECTIVE: To isolate and culture articular cartilage surface cells from mice and to verify the effect of epidermal growth factor receptor signaling pathway on the proliferation, differentiation and apoptosis of articular cartilage surface cells. METHODS: Articular cartilage surface cells from mice were isolated and cultured in vitro by fibronectin adhesion and enzyme digestion and identified. Passage 3 cells were separately treated with transforming growth factor α (100 μg/L), Gefitinib (10 μmol/L), and conventional medium (control group). Cell proliferation was detected by cell counting kit-8 and Ki67 gene expression was detected by RT-PCR. Cell apoptosis was induced by transforming growth factor α (25 μg/L) and AOEB staining was used to identify the apoptosis. RT-PCR was used to detect the expression of Bcl2 and Bax genes. Chondrogenic, osteogenic, and adipogenic induction were conducted for 14-21 days in each group and the mRNA expressions of Sox9, Runx2, and lipoprotein lipase were detected by RT-PCR. RESULTS AND CONCLUSION: Articular cartilage surface cells isolated and cultured in vitro were long-shaped and positively expressed PRG4 identified by immunofluorescence. Cell counting kit-8 results showed that after treatment with transforming growth factor α, cell proliferation ability and the mRNA level of Ki67 were significantly increased (P < 0.05). AOEB staining results showed that after treatment with transforming growth factor α, the apoptotic level was significantly decreased, the mRNA level of Bcl2 was significantly increased (P < 0.05), and the mRNA level of Bax was significantly decreased (P < 0.05). RT-PCR results revealed that the mRNA level of Runx2 was significantly increased (P < 0.05) and the mRNA level of Sox9 was significantly decreased after treatment with transforming growth factor α. To conclude, the epidermal growth factor receptor signaling pathway is involved in the proliferation, differentiation, and apoptosis of articular surface chondrocytes. Epidermal growth factor receptor mediated by transforming growth factor α can promote the proliferation and osteogenic differentiation of articular cartilage surface cells and inhibit the chondrogenic differentiation and apoptosis of articular cartilage surface cells. [ABSTRACT FROM AUTHOR]

BACKGROUND: It has been found in recent observational studies that assessing localized fat mass is crucial in the evaluation of disc degeneration. Although obesity has been recognized as a risk factor for disc degeneration, the causal relationship between fat mass, which is a key factor in obesity, and intervertebral disc degeneration has been unclear in previous studies. OBJECTIVE: To investigate the causal risk factors of intervertebral disc degeneration associated with different distributions of fat mass, thereby enhancing the understanding of the pathogenesis of intervertebral disc degeneration and contributing to the development of preventive, therapeutic, and prognostic strategies. METHODS: Genetic markers associated with trunk and lower limb fat mass were extracted as instrumental variables from the publicly available IEU Open GWAS under the conditions of strong correlation and fulfillment of linkage disequilibrium. These markers were combined with the Mendelian randomization analysis to investigate the relationship between body fat and intervertebral disc degeneration. We used the latest version 9 database of FinnGen and assessed the results using several regression models, including inverse variance weighting, MR-Egger regression, simple mode, weighted mode, and weighted median estimator. We also assessed the heterogeneity of the genetic markers using Cochran’s Q test, and multiplicity was assessed using the MR-Egger intercept test. Additionally, we used the leave-one-out method to determine the sensitivity of individual genetic markers to the causal effect of the exposure and outcome. The results were presented as odds ratios (OR) and 95% confidence intervals (CI). RESULTS AND CONCLUSION: The results from the inverse variance weighting method revealed that there was a positive causal relationship between trunk fat mass and the risk of developing intervertebral disc degeneration (OR=1.25, 95% CI: 1.15-1.35, P < 0.001). Additionally, there was an inverse causal relationship between bilateral lower limb fat mass and the risk of developing intervertebral disc degeneration (OR=0.7, 95% CI: 0.63-0.78, P < 0.001; OR=0.69, 95% CI: 0.62-0.76, P < 0.001). Furthermore, the MR-Egger intercept analysis did not detect any potential horizontal pleiotropy. No bias single nucleotide polymorphisms were detected, while heterogeneity tests were present, and the leave-one-out sensitivity analysis suggested reliable results. The results above demonstrate a positive causal relationship between trunk fat mass and intervertebral disc degeneration. As trunk fat mass increases, the risk of intervertebral disc degeneration rises. With an increase in both lower limb fat mass, the risk of intervertebral disc degeneration decreases. Fat content and distribution affects the risk of developing intervertebral disc degeneration and should be given more attention. [ABSTRACT FROM AUTHOR]

BACKGROUND: Contrast-induced nephropathy has become one of the main causes of hospital-acquired acute kidney injury and its essence is acute renal ischemia-reperfusion injury. However, the role of sirtuin 3 in it is still unclear. OBJECTIVE: To probe the dynamical changes of sirtuin 3 after different duration of renal ischemia and to establish the relationship of sirtuin3 expression with mitochondrial injury-related parameters. METHODS: The mouse model of acute renal ischemia-reperfusion injury was established by ischemia for different time (15, 20, 25, 30 minutes) followed by 48 hours of reperfusion in C57BL/6 mice. According to the ischemic time, all animals were divided into six groups (n=8 per group): control group, sham group, 15-, 20-, 25- and 30-minute ischemia groups. Forty-eight hours after modeling, the serum levels of creatinine and blood urea nitrogen were measured. The apoptosis of renal tissue cells was monitored by TUNEL. Adenosine triphosphate content in the kidney was measured by luciferase luminescence method. Hematoxylin-eosin staining was used to observe pathological changes of the kidney. Mitochondrial changes were observed under a transmission electron microscope. The expression of mitochondrial dynamin related protein 1, mitofusion 1, and sirtuin 3 was determined by western blot. RESULTS AND CONCLUSION: After ischemia, serum ccreatinine, blood urea nitrogen, histopathological score and apoptotic index increased gradually after ischemia; the injury of mitochondrial structure of the kidney gradually aggravated and the mitochondrial adenosine triphosphate content decreased in general. The sirtuin 3 expression showed no significant difference among control, sham and 15-minute ischemia groups. The expression of sirtuin 3 was higher at 20 minutes of ischemia than at 15 minutes of ischemia (P < 0.05), further increased significantly at 25 minutes of ischemia (P < 0.05), and reached a peak at 30 minutes of ischemia (P < 0.05). Mitofusion 1 expression significantly increased in the 15- and 20-minute ischemia groups compared with the sham group (P < 0.05) and further increased significantly in the 25- and 30-minute ischemia groups compared with the 15-minute ischemia group (P < 0.05). The expression of mitochondrial dynamin related protein 1 increased to the peak value at 15 minutes (P < 0.05) and then decreased at 20 and 25 minutes. Relationship study showed that the content of adenosine triphosphate was negatively correlated with the expression of sirtuin 3 (r=-0.77, P < 0.05). The expression of sirtuin 3 was negatively correlated with the expression of mitochondrial dynamin related protein 1 (r=-0.52, P < 0.05). The expression of sirtuin 3 was positively correlated with the expression of mitofusion 1 (r=0.72, P < 0.05). To conclude, during renal ischemia-reperfusion injury, the decreased adenosine triphosphate level time-dependently stimulates the expression of sirtuin 3. The over expression of sirtuin3 enhances mitochondrial fusion and inhibit its fission, then protect the mitochondria and maintain energy metabolism. All these findings indicate that sirtuin3 may be a potential target for reducing renal ischemia-reperfusion injury. [ABSTRACT FROM AUTHOR]

BACKGROUND: The important pathological change of osteoarthritis is the degeneration of articular cartilage. Transforming growth factor β1 and Ras homolog gene family member A play an important role in maintaining the stability of articular cartilage and the occurrence and development of osteoarthritis, respectively. OBJECTIVE: To investigate the effects of transforming growth factor-β1 and Ras homolog gene family member A on chondrocyte morphology, cytoskeleton and expression of related factors during chondrocyte differentiation, and the mutual regulation relationship between transforming growth factor-β1, Ras homolog gene family member A and SRY related HMG box-9. METHODS: Exogenous transforming growth factor β1 at different concentrations was added to stimulate ATDC5 cells to detect the protein expression of Ras homolog gene family member A and SRY related HMG box-9 at different times. Transforming growth factor-β1, LY-364947 (a potent ATP-competitive inhibitor of transforming growth factor-β receptor I) and lysophosphatidic acid (a Ras homolog gene family member A agonist) were used in different combinations to deal with ATDC5 cells for 72 hours. The protein expression levels of Ras homolog gene family member A, SRY related HMG box-9 and transforming growth factor-β were detected, and the changes in cell morphology and cytoskeleton were also observed. RESULTS AND CONCLUSION: With the increase of transforming growth factor-β1 concentration and time, the expression levels of Ras homolog gene family member A and SRY related HMG box-9 proteins increased significantly (P < 0.001). Compared with the control group, lysophosphatidic acid significantly increased the expression levels of Ras homolog gene family member A and SRY related HMG box-9 protein (P < 0.001), but lysophosphatidic acid treatment had no effect on the protein expression level of transforming growth factor-β1 (P > 0.05). The combination of transforming growth factor-β1 and lysophosphatidic acid significantly increased the protein levels of transforming growth factor-β1, Ras homolog gene family member A, and SRY related HMG box-9 in the treated cells (P < 0.001). LY-364947 decreased the protein levels of RhoA and SRY related HMG box-9 (P < 0.001), and significantly reduced the activation effects of lysophosphatidic acid on Ras homolog gene family member A and SRY related HMG box-9 (P < 0.001). Compared with the control group, after treatment with transforming growth factor-β1, lysophosphatidic acid and their combination, the cell morphology was elongated, the intracellular actin filaments were arranged in a more orderly manner, and the number of actin filaments aggregated at the cell edge was increased. LY-364947 made the morphology of cells become polygonal, the arrangement of actin filaments was disordered, and the actin filaments at the edge of cells decreased. The changes in cell morphology and cytoskeleton by LY-364947+lysophosphatidic acid treatment were similar to those in the LY-364947 treatment group. Therefore, in ATDC5 cells, transforming growth factor-β1 has a superposition effect on Ras homolog gene family member A and SRY related HMG box-9 protein expression in concentration, dose and time. Transforming growth factor-β1 may be the upstream factor of Ras homolog gene family member A and SRY related HMG box-9, regulates the expression of Ras homolog gene family member A and SRY related HMG box-9 to regulate the function of cytoskeleton, and thus participates in the development and progression of osteoarthritis. [ABSTRACT FROM AUTHOR]

BACKGROUND: Both rhesus monkeys and humans belong to primates, and their cervical vertebra structure, physiological function and living conditions are very similar to those of human beings. However, there are few studies on the finite element analysis of the whole cervical vertebra of rhesus monkeys. OBJECTIVE: To establish the C0-T1 finite element model of cervical vertebrae of adult rhesus monkeys and to make a comparative study between the finite element models of cervical vertebrae of adult rhesus monkeys and human cervical vertebrae in order to find out the difference. METHODS: A 7-year-old adult male rhesus monkey was selected and scanned by multi-slice spiral CT in the Imaging Department of the affiliated Hospital of Inner Mongolia Medical University in December 2019. The original CT data of cervical vertebrae were introduced into Mimics21.0 to establish a preliminary three-dimensional model, and the geometric structure of the model was optimized by Cero to get the simulation three-dimensional model of cervical vertebrae. The assembly model was imported into Hypermesh for tetrahedral gridding to divide the tissue grids of various segments, intervertebral discs and ligaments of cervical vertebrae. Then the finite element model of cervical vertebra was constructed by Abaqus&ANSYS, and the validity was verified by referring to the relevant finite element model literature. RESULTS AND CONCLUSION: The three-dimensional finite element model of cervical vertebra of rhesus monkey (including C0-T1 and six intervertebral discs and related ligaments) was successfully established, with a total of 536 215 elements and 461 915 nodes. The overall simulation of the model was high, and the fine structure was restored with high precision, resulting in a high biological simulation performance. Comparing the range of motion of this model with that of human cervical vertebra model, we found that the flexion and extension of this model were smaller than those of normal adults (P < 0.05), and left and right lateral bending of C2-3, C3-4 and C6-7 segments was smaller than the range of standard deviation as reported (P < 0.05). However, axial rotation showed no significant difference as compared with the value reported previously (P > 0.05). To conclude, there is a great difference in the exercise efficiency between the finite element models of rhesus monkey cervical vertebra and human cervical vertebra, which can provide a theoretical basis for the study of rhesus monkey cervical vertebra modeling. [ABSTRACT FROM AUTHOR]

BACKGROUND: Studies have shown that the occurrence of osteosarcoma is associated with abnormal expression of various microRNAs (miRNAs). Exosomes (Exos) containing miRNAs get much more attentions in intracellular communications. OBJECTIVE: To investigate the effects of exosomal miR-1307 from osteosarcoma on proliferation and apoptosis of osteosarcoma cells and its mechanism. METHODS: Human osteosarcoma cell lines (143B, MG63, U2OS, Saos-2 and SW1353) and human normal osteoblastic cell line (hFOB 1.19) were purchased. The expression level of miR-1307 in five kinds of osteosarcoma cell lines and normal osteoblastic cell line was detected by qRT-PCR. Finally, SW1353 cell line was selected for functional verification of osteosarcoma cells. Osteosarcoma cells and normal osteoblasts were cultured. Osteosarcoma exosomes and normal osteoblastic exosomes were extracted by differential centrifugation. Then miR-1307 inhibitor and miR-NC mimic were transfected into SW1353 osteosarcoma cells and normal osteoblasts, and then SW1353 osteosarcoma cell exosomes and normal osteoblast exosomes were extracted. The above exosomes (25 mg/L) were added to SW1353 osteosarcoma cells to intervene for 24 hours. Cell proliferation assay and flow cytometry were used to observe the proliferation and apoptosis of osteosarcoma cells. Targetscan, miRBase and miRDIP databases were used to predict the target genes of miR-1307. The activity of luciferin was assayed by luciferase reporter gene. mRNA and protein expression levels of AGAP1 were assayed by qRT-PCR and western blot assay in osteosarcoma cells. RESULTS AND CONCLUSION: (1) Compared with hFOB 1.19-exosomes of osteoblasts, SW1353 osteosarcoma cell exosomes significantly promoted the proliferation and inhibited the apoptosis of osteosarcoma cells (P < 0.01). Compared with SW1353 osteosarcoma cell exosomes, the level of miR-1307 in SW1353 osteosarcoma cell exosomes was down-regulated; the proliferation of osteosarcoma cells was significantly decreased but the apoptosis rate was significantly increased (P < 0.01). (2) AGAP1 was verified as a direct target gene of miR-1307. Compared with miR-NC, miR-1307 significantly inhibited the mRNA and protein levels of AGAP1 (P < 0.01). Compared with miR-NC, miR-1307 significantly inhibited the luciferase activity of wild-type PGLO-AGAP1-WT 3'-UTR (P < 0.05). (3) The results show that exosomal miR-1307 of osteosarcoma promoted the proliferation and inhibited the apoptosis of osteosarcoma cells via targeting AGAP1. [ABSTRACT FROM AUTHOR]

BACKGROUND: Human bone marrow mesenchymal stem cells can be induced to differentiate into hapatocytes without mature function. Long-chain non-coding RNA (lncRNA) plays an important part in the differentiation of mesenchymal stem cells. To date, there is still no report on whether the lncRNA highly up-regulated in liver cancer (HULC) is involved in the differentiation of bone marrow mesenchymal stem cells into hepatocytes. OBJECTIVE: To investigate the mechanism of lncRNA HULC in the differentiation of human bone marrow mesenchymal stem cells into hepatocyte-like cells. METHODS: Human bone marrow mesenchymal stem cells were purchased from the Cell Bank of Chinese Academy of Sciences, Shanghai, China and were cultured in the hepatic differentiation medium containing cytokines in vitro. After 4 weeks of induction, cell morphology was observed under inverted microscope. Hepatocyte specific proteins were analyzed by immunofluorescence. The expression of IncRNA HULC was examined by qRT-PCR. Bone marrow mesenchymal cell lines stably expressing IncRNA HULC were then produced through lentiviral transfection. Bone marrow mesenchymal stem cells transfected with negative lentivirus were used as controls. Two groups of cells were concurrently induced with the hepatic differentiation medium containing cytokines. The expressions of hepatocyte specific genes and proteins were detected and compared between the two groups by qRT-PCR and western blot, respectively. RESULTS AND CONCLUSION: Human bone marrow mesenchymal stem cells could be successfully induced into hepatocytes in vitro through the addition of cytokines. The expression of IncRNA HULC was gradually increased during the differentiation. Overexpression of IncRNA HULC caused a marked increase in the expression of hepatocyte specific genes and proteins. To conclude, IncRNA HULC plays an important role in the differentiation of human bone marrow mesenchymal stem cells into hepatocytes. It will provide a theoretical basis for the application of cell therapy in liver diseases. [ABSTRACT FROM AUTHOR]