Feasibility of repairing skin defects by VEGF165 gene-modified iPS-HFSCs seeded on a 3D printed scaffold containing astragalus polysaccharide.

The preparation of biodegradable scaffolds loaded with cells and cytokine is a feature of tissue-engineered skin. IPSCs-based tissue-engineered skin treatment for wound repair is worth exploring. Healthy human skin fibroblasts were collected and reprogrammed into iPSCs. After gene modification and induction, CK19+ /Integrinß1+ /CD200+ VEGF165 gene-modified iPS-HFSCsGFP were obtained and identified by a combination of immunofluorescence and RT-qPCR. Astragalus polysaccharide-containing 3D printed degradable scaffolds were prepared and co-cultured with VEGF165 gene-modified iPS-HFSCsGFP , and the biocompatibility and spatial structure of the tissue-engineered skin was analysed by cell counting kit-8 (CCK8) assay and scanning electron microscopy. Finally, the tissue-engineered skin was transplanted onto the dorsal trauma of nude mice, and the effect of tissue-engineered skin on the regenerative repair of total skin defects was evaluated by a combination of histology, immunohistochemistry, immunofluorescence, RT-qPCR, and in vivo three-dimensional reconstruction under two-photon microscopy. CK19+ /Integrinß1+ /CD200+ VEGF165 gene-modified iPS-HFSCsGFP , close to the morphology and phenotype of human-derived hair follicle stem cells, were obtained. The surface of the prepared 3D printed degradable scaffold containing 200 µg/mL astragalus polysaccharide was enriched with honeycomb-like meshwork, which was more conducive to the proliferation of the resulting cells. After tissue-engineered skin transplantation, combined assays showed that it promoted early vascularization, collagen and hair follicle regeneration and accelerated wound repair. VEGF165 gene-modified iPS-HFSCsGFP compounded with 3D printed degradable scaffolds containing 200 µg/mL astragalus polysaccharide can directly and indirectly participate in vascular, collagen, and hair follicle regeneration in the skin, achieving more complete structural and functional skin regenerative repair.

Single-cell RNA-seq reveals altered NK cell subsets and reduced levels of cytotoxic molecules in patients with ankylosing spondylitis.

Ankylosing spondylitis (AS) is an autoimmune disease with unknown aetiology. To unravel the mechanisms mediating AS pathogenesis, we profiled peripheral blood mononuclear cells (PBMCs) from AS patients and healthy subjects using 10X single-cell RNA sequencing. The frequencies of immune cell subsets were evaluated by flow cytometry. NK cells were purified from PBMCs using isolation kit and were examined for gene expression by RT-qPCR. Plasma levels of cytolytic molecules were examined by enzyme-linked immunosorbent assay. Compared to healthy controls, AS patients showed a significant decrease in total NK cells as well as CD56dim NK subset, whereas CD56bright NK cells were increased. Additionally, impaired expression of cytotoxic genes in NK cells of AS patients was observed by bioinformatics algorithm and verified by RT-qPCR and flow cytometry. Consistent with changes in transcriptomics, we found decreased plasma levels of granzymes, but not granulysin, in AS patients. Furthermore, Pearson correlation analysis revealed a negative correlation between plasma GZMB levels and disease activity (r = -0.5275, p = 0.0358). No correlation was observed between plasma cytolytic molecules and biochemical indexes (ESR and CRP). Our findings uncover altered NK cell subsets and cytotoxic profiles in peripheral circulation of AS patients at single-cell resolution.

Development and application of CRISPR/Cas9 technologies in genomic editing.

Genomic editing to correct disease-causing mutations is a promising approach for the treatment of human diseases. As a simple and programmable nuclease-based genomic editing tool, the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) system has substantially improved the ability to make precise changes in the human genome. Rapid development of CRISPR-based technologies in recent years has expanded its application scope and promoted CRISPR-based therapies in preclinical trails. Here, we review the application of the CRISPR system over the last 2 years; including its development and application in base editing, transcription modulation and epigenetic editing, genomic-scale screening, and cell and embryo therapy. Finally, the prospects and challenges related to application of CRISPR/Cas9 technologies are discussed.

Space microgravity drives transdifferentiation of human bone marrow-derived mesenchymal stem cells from osteogenesis to adipogenesis.

Bone formation is linked with osteogenic differentiation of mesenchymal stem cells (MSCs) in the bone marrow. Microgravity in spaceflight is known to reduce bone formation. In this study, we used a real microgravity environment of the SJ-10 Recoverable Scientific Satellite to examine the effects of space microgravity on the osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (hMSCs). hMSCs were induced toward osteogenic differentiation for 2 and 7 d in a cell culture device mounted on the SJ-10 satellite. The satellite returned to Earth after going through space experiments in orbit for 12 d, and cell samples were harvested and analyzed for differentiation potentials. The results showed that space microgravity inhibited osteogenic differentiation and resulted in adipogenic differentiation, even under osteogenic induction conditions. Under space microgravity, the expression of 10 genes specific for osteogenesis decreased, including collagen family members, alkaline phosphatase ( ALP), and runt-related transcription factor 2 ( RUNX2), whereas the expression of 4 genes specific for adipogenesis increased, including adipsin ( CFD), leptin ( LEP), CCAAT/enhancer binding protein ß ( CEBPB), and peroxisome proliferator-activated receptor-γ ( PPARG). In the analysis of signaling pathways specific for osteogenesis, we found that the expression and activity of RUNX2 was inhibited, expression of bone morphogenetic protein-2 ( BMP2) and activity of SMAD1/5/9 were decreased, and activity of focal adhesion kinase (FAK) and ERK-1/2 declined significantly under space microgravity. These data indicate that space microgravity plays a dual role by decreasing RUNX2 expression and activity through the BMP2/SMAD and integrin/FAK/ERK pathways. In addition, we found that space microgravity increased p38 MAPK and protein kinase B (AKT) activities, which are important for the promotion of adipogenic differentiation of hMSCs. Space microgravity significantly decreased the expression of Tribbles homolog 3 ( TRIB3), a repressor of adipogenic differentiation. Y15, a specific inhibitor of FAK activity, was used to inhibit the activity of FAK under normal gravity; Y15 decreased protein expression of TRIB3. Therefore, it appears that space microgravity decreased FAK activity and thereby reduced TRIB3 expression and derepressed AKT activity. Under space microgravity, the increase in p38 MAPK activity and the derepression of AKT activity seem to synchronously lead to the activation of the signaling pathway specifically promoting adipogenesis.-Zhang, C., Li, L., Jiang, Y., Wang, C., Geng, B., Wang, Y., Chen, J., Liu, F., Qiu, P., Zhai, G., Chen, P., Quan, R., Wang, J. Space microgravity drives transdifferentiation of human bone marrow-derived mesenchymal stem cells from osteogenesis to adipogenesis.

VEGF165 induces differentiation of hair follicle stem cells into endothelial cells and plays a role in in vivo angiogenesis.

Within the vascular endothelial growth factor (VEGF) family of five subtypes, VEGF165 secreted by endothelial cells has been identified to be the most active and widely distributed factor that plays a vital role in courses of angiogenesis, vascularization and mesenchymal cell differentiation. Hair follicle stem cells (HFSCs) can be harvested from the bulge region of the outer root sheath of the hair follicle and are adult stem cells that have multi-directional differentiation potential. Although the research on differentiation of stem cells (such as fat stem cells and bone marrow mesenchymal stem cells) to the endothelial cells has been extensive, but the various mechanisms and functional forms are unclear. In particular, study on HFSCs' directional differentiation into vascular endothelial cells using VEGF165 has not been reported. In this study, VEGF165 was used as induction factor to induce the differentiation from HFSCs into vascular endothelial cells, and the results showed that Notch signalling pathway might affect the differentiation efficiency of vascular endothelial cells. In addition, the in vivo transplantation experiment provided that HFSCs could promote angiogenesis, and the main function is to accelerate host-derived neovascularization. Therefore, HFSCs could be considered as an ideal cell source for vascular tissue engineering and cell transplantation in the treatment of ischaemic diseases.

Treatment of Neer IIb Distal Clavicle Fractures Using Anatomical Locked Plate Fixation With Coracoclavicular Ligament Augmentation.

PURPOSE: The purpose of this study was to evaluate the clinical and radiographic outcomes of Neer type IIb distal clavicle fractures treated with anatomical locking plate fixation combined with coracoclavicular ligament augmentation. METHODS: Twelve patients with Neer Type IIb distal clavicle fractures treated with anatomical locking plate fixation combined with suture anchor augmentation of the coracoclavicular ligament, were retrospectively studied. Clinical outcomes were assessed using the Constant score and the Disabilities of the Arm, Shoulder, and Hand (DASH) score. Coracoclavicular distance was measured on plain radiographs. RESULTS: All patients were reexamined at a mean follow-up of 26.3 months (range, 25-30 months). Bony union occurred in all cases within 12 weeks and no major complications were encountered. At the final follow-up, the mean Constant score was 94 (range, 87-100) and the DASH score was 10.4 (range, 2-20). The mean postoperative coracoclavicular distance on the injured side was decreased by 40% compared with the preoperative status. CONCLUSIONS: Surgical fixation of Neer type IIb distal clavicle fractures using anatomical locking plate fixation combined with suture anchor augmentation of the coracoclavicular ligament was associated with a satisfactory functional outcome and low complication rate. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

[Effect of moxa-burning heat stimulating Liangmen (ST 21) and Zusanli (ST 36) on proliferation and apoptosis signaling proteins in rats with stress-induced gastric ulcer].

OBJECTIVE: To observe the effect of moxa-burning heat stimulating acupoints of Liangmen (ST 21) and Zusanli (ST 36) on the proliferation and apoptosis signaling proteins in rats with stress-induced gastric ulcer. METHODS: Forty rats were randomly divided into four groups: negative control (NC), ulcer control (UC), acupoints of stomach meridian (ASM), and acupoints control (AC). The acute gastric ulcer model was established by bound and water immersion. Rats in NC and UC groups didn't receive any moxa-burning heat stimulating treatment, while rats in ASM and AC groups were treated with buringmoxa heat stimulating the acupoints of Liangmen (ST 21) and Zusanli (ST 36) and their controlled points, respectively. Rats in all groups were sacrificed after 12 consecutive days treatment. The ulcer index was evaluated by using Guth's method. The expression of tumor necrosis factor-alpha (TNF-α), apoptotic protease activating facter-1 (Apaf-1), Caspase-3, p21 activated kinase 1 (PAK1), extracellular regulated protein kinases 2 (ERK2), phosphorylated ERK2 (pERK2), phosphoinositide 3-kinase (PI3K) and RAC-alpha serine/threonine-protein kinase (Akt) in gastric mucosa was detected by enzyme linked immunosorbent assay (ELISA). RESULTS: Compared with UC group, the ulcer index of ASM and AC groups decreased, and the injured gastric mucosa was improved, the expression of TNF-α, Apaf-1 and Caspase-3 in gastric mucosa was significantly reduced (P < 0.05), while the expression of PAK1, ERK2, pERK2, PI3K and Akt in gastric mucosa was significantly increased (P < 0.05). And ASM showed better effect than AC group (P < 0.05). CONCLUSION: Moxa-burning Heat stimulating of Liangmen (ST 21) and Zusanli (ST 36) could promote the recovery of gastric mucosal lesion probably by inhibiting cell apoptosis and promoting cell proliferation in stress-induced gastric ulcer.

Analysis of the outcome of bi-vertebral transpedicular wedge osteotomy for correcting severe kyphotic deformity in ankylosing spondylitis.

To study the outcomes of bi-vertebral transpedicular wedge osteotomy in correcting severe kyphotic deformity in ankylosing spondylitis (AS). This retrospective study focused on all the patients who underwent thoracic and lumbar bi-vertebra transpedicular wedge osteotomy with pedicle screw internal fixation to treat their severe thoracolumbar kyphotic deformity of AS in our hospital from January 2014 to January 2020. The perioperative and operative data of each patient were collected and analyzed. A total of 21 male AS patients with severe kyphotic deformity were studied with a mean age of 42.2 ± 9.2 years. Intraoperatively, the mean operating time is 5.8 ± 1.6 hour with a mean blood loss of 725.5 ± 140.6 mL. The average postoperative correction of kyphosis reached 60.8o at 1 week after the surgery, which is significantly improved from preoperative presentation (P < .05), and stayed no significant change over the time during longer period of follow-ups (12-24 months) with the overall correction rate of 72.2%. Moreover, the postoperative changes in thoracic kyphosis (TK) angle, thoracolumbar kyphosis (TLK) angle, lumbar lordosis (LL) angle, maxilla-brow angle, as well as C2SVA and C7SVA sagittal balance were also significant, all of which enabled the patients to walk in upright position and sleep in the supine position with the improvements in other clinical symptoms. Bi-vertebral transpedicular wedge osteotomy of thoracic and lumbar vertebrae is a safe and effective method to restore the physiological curvature of the sagittal position of the spine and correct severe ankylosing deformity.

[Aconite-isolated moxibustion at Yongquan (KI 1) combined with rivaroxaban for lower extremity venous thrombosis after total knee arthroplasty: a randomized controlled trial].

OBJECTIVE: To investigate the clinical effect of aconite-isolated moxibustion at Yongquan (KI 1) combined with rivaroxaban for lower extremity venous thrombosis after total knee arthroplasty and the influence on hypercoagulation. METHODS: Seventy-three patients of knee osteoarthritis with lower extremity venous thrombosis after total knee arthroplasty (KOA) were randomly divided into an observation group (37 cases, 2 cases dropped off) and a control group (36 cases, 1 case dropped off). The patients in the control group took orally rivaroxaban tablets, 10 mg a time, once a day. On the basis of the treatment as the control group, the aconite-isolated moxibustion was applied to Yongquan (KI 1) for the patients of the observation group, once daily and 3 moxa cones were used in each treatment. The duration of treatment was 14 days in both groups. Before treatment and 14 days into treatment, the ultrasonic B test was adopted to determine the conditions of lower extremity venous thrombosis in the two groups. Before treatment, 7 and 14 days into treatment, the coagulation indexes (platelet [PLT], prothrombin time [PT], activated partial prothrombin time [APTT], fibrinogen [Fib] and D-dimer[D-D]), the blood flow velocity of the deep femoral vein and the circumference of the affected side were compared between the two groups separately, and the clinical effect was evaluated. RESULTS: Fourteen days into treatment, the venous thrombosis of the lower extremity was relieved in both groups (P<0.05), and that of the observation group was better than the control group (P<0.05). Seven days into treatment, the blood flow velocity of the deep femoral vein was increased compared with that before treatment in the observation group (P<0.05), and the blood flow rate in the observation group was higher than that in the control group (P<0.05). Fourteen days into treatment, PT, APTT and the blood flow velocity of the deep femoral vein were increased in the two groups compared with those before treatment (P<0.05); and PLT, Fib, D-D and the circumference of the limb (knee joint, 10 cm above the patella and 10 cm below the patella) were all reduced in the two groups (P<0.05). Compared with the control group 14 days into treatment, the blood flow velocity of the deep femoral vein was higher (P<0.05), PLT, Fib, D-D and the circumference of the limb (knee joint, 10 cm above the patella and 10 cm below the patella) were all lower in the observation group (P<0.05). The total effective rate was 97.1% (34/35) in the observation group, higher than 85.7% (30/35) in the control group (P<0.05). CONCLUSION: Aconite-isolated moxibustion at Yongquan (KI 1) combined with rivaroxaban can effectively treat lower extremity venous thrombosis after total knee arthroplasty, relieve hypercoagulation, accelerate the blood flow velocity and alleviate swelling of the lower extremity in the patients with knee osteoarthritis.

Recent Efficacy of Oblique Lateral Interbody Fusion Combined With Wiltse Approach Pedicle Screw Fixation for Degenerative Single-Level Lumbar Spondylolisthesis.

BACKGROUND: The study aimed to explore the recent efficacy of oblique lateral interbody fusion (OLIF) combined with Wiltse approach pedicle screw fixation in the treatment of single-level degenerative lumbar spondylolisthesis (DLS). METHODS: This is a retrospective study. The study enrolled 54 patients with single-level DLS who were treated at the Affiliated Jiangnan Hospital of Zhejiang Chinese Medical University from May 2018 to June 2020. (OLIF group) 24 cases operated using OLIF combined with Wiltse approach pedicle screw fixation, and (PLIF group) 30 cases operated by PLIF. The primary outcome measures were visual analog scale (VAS) pain scores, Oswestry dysfunction index (ODI), and the lower lumbar spine anterior convexity angle. RESULTS: There were significant differences in VAS (2.63 ± 0.58 vs. 3.57 ± 0.63, P < 0.001) and ODI (9.67 ± 0.92 vs. 10.63 ± 1.40, P < 0.05) between the OLIF group and PLIF group on postoperative 3 days. And there was a significant decrease in VAS (2.63 ± 0.58 vs. 1.08 ± 0.28, P < 0.05) and ODI (3.57 ± 0.63 vs. 1.10 ± 0.31, P < 0.05) in both groups on postoperative 3 days and at 6 months postoperative comparisons. OLIF group showed better intervertebral space height and the lower lumbar spine anterior convexity angle scores on postoperative 3 days and 6 months, the difference was statistically significant(all P < 0.05). CONCLUSIONS: OLIF combined with the Wiltse approach pedicle screw fixation can achieve good short-term clinical results in the treatment of single-level DLS. This surgical approach is less invasive, promotes early functional recovery, shortens hospitalization time, and improves the quality of life.

Association between urinary glyphosate exposure and bone mineral density in adults.

There is very limited evidence linking glyphosate exposure to bone mineral density in adults aged 20 to 59 years in the National Health and Nutrition Examination Survey database. Hence, this study aimed to investigate the correlation between urinary glyphosate concentrations and total bone mineral density (BMD) in adults aged 20 to 59 years. A cross-sectional study was conducted using data from the 2013 to 2016 National Health and Nutrition Examination Survey, which included 594 men (mean age 39.1 years) and 610 women (mean age 40.0 years). In our study, we utilized a weighted multiple regression equation model to investigate the potential correlation between urinary glyphosate concentration and total BMD. Additionally, we conducted a stratified analysis to differentiate between various special populations. Our findings revealed a significant negative association between urinary glyphosate concentration and total BMD across 3 different regression models (Model 1, ß [95% CI]: -0.0160 [-0.0200, -0.0120]; Model 2, ß [95% CI]: -0.0135 [-0.0172, -0.0098]; Model 3, ß [95% CI]: -0.0141 [-0.0178, -0.0104]). However, after stratifying by gender, age, and race, we observed varying conclusions. This study found that urinary glyphosate concentration was negatively associated with total BMD in both men and women when stratified by sex. Additionally, when stratified by age, the negative association was more significant in the 20 to 29 and 50 to 59 year age groups. When stratified by race, a significant negative association was found in races other than Hispanic. Therefore, the impact of glyphosate exposure on BMD should attract more people's attention.

Association between the ratio of serum creatinine to cystatin C and bone mineral density in middle-aged and older adults: a cross-sectional study from NHANES database.

OBJECTIVE: To investigate the association between creatinine to cystatin C ratio (CCR) and bone mineral density (BMD) in middle-aged and older adults. METHODS: This cross-sectional study investigated participants aged 50-85, using National Health and Nutrition Examination Survey (NHANES) data from 1999 to 2002. The correlation between CCR and total BMD was assessed by multivariate linear regression models, using stratified analysis by age, sex and race (Mexican American, other Hispanic, non-Hispanic White, non-Hispanic Black, and other race) to distinguish various special populations. RESULTS: Among 2992 patients, multiple regression models revealed a significant positive correlation between CCR and total BMD: model 1, 0.030 (95% confidence interval [CI] 0.029, 0.031); model 2, 0.009 (95% CI 0.008, 0.010); model 3, 0.010 (95% CI 0.009, 0.013). After controlling for all covariates, a positive correlation was observed between CCR and total BMD in both men and women, and was further strengthened in older age groups. When stratifying by race, the positive correlation was most significant among 'other Hispanic' participants; there was no significant correlation among those of 'other race'. CONCLUSIONS: A positive correlation was demonstrated between CCR and total BMD in middle-aged and older adults aged 50-85 years, with the most significant positive correlation in the older 'other Hispanic' population. No significant correlation was observed among participants of 'other race'.

Association between creatine phosphokinase level within normal range and bone mineral density in adolescents.

Currently, it is unclear whether creatine phosphokinase (CPK) affects bone mineral density (BMD) in adolescents. We sought to clarify the relationship between CPK and total BMD in adolescents aged 12 to 19 years within normal values by conducting this study. A cross-sectional study was conducted using the 2011 to 2018 National Health and Nutrition Survey data to examine 1188 males (average age, 15.2 years) and 1629 females (average age, 15.4 years). In this study, CPK was the independent variable and total BMD was the outcome variable. In addition to using multivariate linear regression models, subgroup analyses were also conducted in order to examine the relationship between CPK levels and total BMD within normal ranges. Significant positive association was observed between the CPK levels and total BMD in adolescents (model 1: 0.0003 [0.0002, 0.0004], model 2: 0.0004 [0.0003, 0.0005] and model 3: 0.0004 [0.0003, 0.0004]). After adjusting for age, gender, race/ethnicity, body mass index, dietary protein intake, dietary protein intake, dietary fiber intake, poverty to income ratio, physical activities, total cholesterol, total protein, blood urea nitrogen, phosphorus, and serum calcium, CPK levels remained significantly associated with BMD (regression coefficients for quartiles 2 to 4 vs quartile1 were 0.0002, 0.0072, and 0.0154, respectively; P for trend <.001). The association was positive even when stratified by age, gender, and race. Further, adolescents aged 16 to 19 years were more likely to report positive relationships than adolescents aged 12 to 15 years. And the phase relationship between total BMD and CPK was further enhanced in boys. The results of our study show that CPK levels within the normal range are positively associated with total BMD in adolescents aged 12 to 19 years. Additionally, CPK may be a potential biomarker of bone health among adolescents.

Case series: O-arm navigation assisted by the Wiltse approach improves the accuracy of pedicle screw placement in ankylosing spondylitis combined with thoracolumbar fractures.

Here we assessed the accuracy of O-arm navigation assisted by Wiltse approach to improve based pedicle screw insertion in ankylosing spondylitis combined with thoracolumbar fractures. We then compared it with the freehand pedicle screw insertion technique. The study sample included 32 patients with ankylosing spondylitis combined with thoracolumbar fractures. Pedicle screw reduction and internal fixation was performed under an O-arm navigation system assisted by a Wiltse approach-combined osteotomy ("navigation group," n = 17) and posterior pedicle screw reduction and internal fixation was performed using freehand technique combined osteotomy ("freehand group," n = 15). We then compared the operation time and bleeding volume between the 2 groups. The visual analog scale (VAS) and Oswestry disability index (ODI) were then used to evaluate the clinical efficacy and the kyphosis Cobb angle was used to evaluate the radiological efficacy before operation, 3 days after operation and after the last follow-up. All complications were noted when detected. Finally, classification of screw positions as proposed by Neo et al was used to evaluate the relationship of the position between the screw, the bone cortex, and the incidence of screw penetration. All patients were followed up for 18 to 36 months (i.e., 24.2 ±â€…3.5 months). The operation time and intraoperative bleeding volume of the navigation group were significantly shorter (lower) than those of the freehand group (P < .05). In addition, Both groups showed significantly decreased VAS, ODI, and Cobb angle 3 days after the operation and at the last follow-up when compared to values recorded pre-operation. However, we found no significant difference in VAS, ODI, and Cobb angle between the 2 groups (P > .05). We identified no complications (e.g., infection, VTE/PE, or nerve injury). Moreover, the pedicle screw placement position of the navigation group was better than that of the freehand group (P < .05), and the screw cortical penetration rate was lower than the freehand group (P < .05). During the process of posterior pedicle screw placement, O-arm navigation assisted by the Wiltse approach can significantly reduce operation time, minimize the amount of bleeding volume, and enhance the accuracy of pedicle screw implantation.

WISP2 downregulation inhibits the osteogenic differentiation of BMSCs in congenital scoliosis by regulating Wnt/ß-catenin pathway.

OBJECTIVES: Bone marrow mesenchymal stem cells (BMSCs) are instrumental in bone development, metabolism, and marrow microenvironment homeostasis. Despite this, the relevant effects and mechanisms of BMSCs on congenital scoliosis (CS) remain undefined. Herein, it becomes our focus to reveal the corresponding effects and mechanisms implicated. METHODS: BMSCs from CS patients (hereafter referred as CS-BMSCs) and healthy donors (NC-BMSCs) were observed and identified. Differentially expressed genes in BMSCs were analyzed utilizing scRNA-seq and RNA-seq profiles. The multi-differentiation potential of BMSCs following the transfection or infection was evaluated. The expression levels of factors related to osteogenic differentiation and Wnt/ß-catenin pathway were further determined as appropriate. RESULTS: A decreased osteogenic differentiation ability was shown in CS-BMSCs. Both the proportion of LEPR+ BMSCs and the expression level of WNT1-inducible-signaling pathway protein 2 (WISP2) were decreased in CS-BMSCs. WISP2 knockdown suppressed the osteogenic differentiation of NC-BMSCs, while WISP2 overexpression facilitated the osteogenesis of CS-BMSCs via acting on the Wnt/ß-catenin pathway. CONCLUSIONS: Our study collectively indicates WISP2 knockdown blocks the osteogenic differentiation of BMSCs in CS by regulating Wnt/ß-catenin signaling, thus providing new insights into the aetiology of CS.

Difference of adherence, proliferation and osteogenesis of mesenchymal stem cells cultured on different HA/ZrO2 composites.

OBJECTIVE: To study the adherence, proliferation and osteogenesis of mesenchymal stem cells (MSCs) cultured on different HA/ZrO2 composites. METHODS: The simplex and graded HA/ZrO2 compo-sites were prepared using dry-laid method. The surface topography of the composites was observed by scanning electron microscope (SEM). The MSCs were isolated from rabbits and cultured on experimental groups (simplex HA/ZrO2 composite, graded HA/ZrO2 composite, pure HA or pure ZrO2 coatings respectively) and control group (ordinary culture plate). Then, we observed the adherence, proliferation and osteogenesis of the MSCs, detected the cellular alkaline phosphatase (ALP) activities, extracted total RNA and detected the mRNA expression of collagen I, osteocalcin and osteopontin using the reverse transcription and polymerase chain reaction (RT-PCR) method. RESULTS: The SEM images confirmed that the surface of the simplex HA/ZrO2 composite was coverd by discon-tiguous HA layer with clear visualization of the partial ZrO2 matrix, while the surface of the graded HA/ZrO2 composite was fairly rough with porosity. X-ray diffraction showed that after high temperature sintering, the ZrO2 phase still remained, while the HA phase was transformed to beta-Ca3(PO4)2 , alpha-Ca3(PO4)2 and CaZrO3 phases on the surface of both composites. Cell culture indicated that the HA/ZrO2 composites supported cell attachment. Neither ALP expression nor mRNA expression of collagen I, osteocalcin or osteopontin from RT-PCR results showed significant deviation among four groups. CONCLUSION: Among these four composites, the graded HA/ZrO2 composite promotes the MSCs proliferation and the osteogenic differentiation to a certain extent.

Study on the mechanism of cadmium chloride pollution accelerating skin tissue metabolism disorder, aging and inhibiting hair regeneration.

Drinking water contaminated by Cd2+ is one of the main pathways for Cd to enter the body. The skin barrier is destroyed when the skin is contaminated by environmental Cd2+, however, the detailed mechanism by which Cd2+ induces skin metabolic disorder, and senescence and affects hair regeneration is not completely understood. In this study, 18 C57BL/6 mice were randomly divided into a Control group, a Low-dose group, and a High-dose group with 6 mice in each group, and intragastrically administered with different concentrations of cadmium chloride once a day, respectively. After 1 month of intervention, the skin tissues on the back of mice were collected for non-targeted metabolomics analysis, and the related proteins were detected by immunofluorescence assay. Non-targeted metabolomics analysis result showed that compared with the Control group, there were 29 different metabolites, mainly including lysophospholipids, fatty acids, and bile acids, in the Low-dose group, and 39 differential metabolites in the High-dose group, in addition to the above compounds, there were more amino acid compounds, and most of the metabolites had a reduced response after administration. Immunofluorescence assay result showed that the higher the concentration of cadmium chloride led to the more obvious the proliferation inhibition and apoptosis promotion effects of skin cells, and the more significant damage to hair follicle stem cells. Thus, our findings demonstrate that cadmium chloride pollution can accelerate skin metabolism disorder, and aging and impair hair regeneration.

CD96 Downregulation Promotes the Immune Response of CD4 T Cells and Associates with Ankylosing Spondylitis.

Inhibitory receptors (IRs) play an indispensable role in regulating T cell activation and expansion. This study is aimed at exploring the correlation between IRs and ankylosing spondylitis (AS). Bioinformatics analysis of two datasets (GSE25101 and GSE73754), including 68 AS cases and 36 healthy controls, demonstrated that "T cell receptor signaling pathway" was significantly enriched, and two IRs (CD112R and CD96) were downregulated in AS cases. Real-time Quantitative PCR Detecting System (qPCR) analysis confirmed the decreased expression of CD112R and CD96 in the peripheral blood of AS patients. Flow cytometry demonstrated that the frequency of CD96-positive cells among CD4 T cells in AS patients was significantly reduced and that expressed on the cells was also significantly lower than the healthy controls. In addition, the expression of CD96 was altered on human primary CD4 T cells extracted from 3 healthy volunteers and cocultured with allogeneic dendritic cells (DCs). Also, low expression of CD96 elevated the phosphorylation of ERK in CD4 T cells and increased the level of TNF-α, IL-23, IL-17A, IL-6, and IFN-γ in the cell culture supernatant. These results suggested that CD96 is crucial for the pathogenesis of AS and may be a potential target in the treatment of the disease.

[Experimental study of proteasome inhibitor MG132 up-regulates Wnt/ß-catenin signaling pathway to improve osteoporosis].

OBJECTIVE: To explore the mechanism of proteasome inhibitor MG132 in improving osteoporosis. METHODS: Total of 32 female SD rats, weighing 220 to 250 g and 8 weeks old, were selected. They were randomly divided into 4 groups(n=8). Rats of group A and group B were cut off ovaris on both sides to make model of osteoporosis, and then they were given proteasome inhibitors MG132 and dimethyl sufoxide (DMSO) respectively. Group C was a sham group and rats were given MG132. Group D was a normal group and rats were given MG132 too. The rats were killed in batches at 6 and 12 weeks after administration, and the femoral neck tissues were obtained. Relevant data were analyzed, such as pathomorphological observation, micro-CT analysis, detection of 20S proteasome activity in tissues, and expression of Wnt and ß-catenin. RESULTS: Morphological observation showed that the trabecular were slightly thinner, reticulated, and occasionally interrupted in group A, while the trabecular were obviously thinner and discontinuous in group B. And the trabecular were intact and arranged reticulated in group C and D. The analysis results of bone mineral density(BMD), bone surface(BS), bone volume/total volume(BV/TV) and trabecular thickness(Tb.Th) showed that group B was worse than other groups in all parameters at different time points(P<0.05), and group A was worse than group C and group D in BS(P<0.05), there was no significant difference in all parameters between group C and group D. RFU value of 20S proteasome in group B was significantly higher than that in other groups(P<0.05). According to the results of Western blot, the gray values of Wnt protein and ß-catenin protein in group A were significantly higher than those in other groups (P<0.05). CONCLUSION: MG-132, a ubiquitin proteasome inhibitor, can regulate Wnt/ß-catenin signaling pathway by inhibiting the degradation of ß-catenin protein, and delaying the occurrence and development of osteoporosis.

[Current understanding of intervertebral space height in anterior cervical fusion].

Anterior cervical fusion surgery is the first choice for spine surgeons in the treatment of cervical spine diseases. It has significant effects in treating cervical degenerative diseases, trauma and tumors and other cervical diseases. In anterior cervical fusion, it is necessary to use a distractor to properly distract the intervertebral space, so as to fully expose and relieve the compressive factors, restore the physiological height, curvature and stability of the lesion segment, and achieve the best surgical effect. However, there is currently no consensus on the standard distraction height for the intervertebral space during anterior cervical surgery. This article reviewsed the progress of intervertebral space height in anterior cervical fusion from three dimensions:the relationship between intervertebral space height and cervical disc degeneration mechanism, the selection of intervertebral space height during operation, the recovery of intervertebral space height and the postoperative effect, so as to provide theoretical basis and reference for spinal surgeons when performing intervertebral distraction during operation.