Biomechanical study of femoral neck system for young patients with nonanatomically reduced femoral neck fractures: a finite element.

BACKGROUND: A consensus regarding the optimal approach for treating femoral neck fractures is lacking. We aimed to investigate the biomechanical outcomes of Femoral Neck System (FNS) internal fixation components in the treatment of nonanatomically reduced femoral neck fractures. METHOD: We constructed two types of femoral neck fractures of the Pauwels classification with angles of 30° and 50°, and three models of anatomic reduction, positive buttress reduction and negative buttress reduction were constructed. Subgroups of 1 to 4 mm were divided according to the distance of displacement in the positive buttress reduction and negative buttress reduction models. The von Mises stress and displacements of the femur and FNS internal fixation components were measured for each fracture group under 2100-N axial loads. RESULTS: When the Pauwels angle was 30°, the positive 1-mm and 2-mm models had lower FNS stress than the negative buttress model. The positive 3- and 4-mm models showed FNS stress similar to that of the negative buttress model. But the four positive buttress models had similar stresses on the femur as the negative buttress model. When the Pauwels angle was 50°, the four positive buttress models had higher FNS stress than the negative buttress model. Three positive buttress models (2 mm, 3 and 4 mm) resulted in lower stress of the femur than the negative buttress model, though the 1-mm model did not. When the Pauwels angle was 30°, the positive buttress model had a lower displacement of the FNS than the negative buttress model and a similar displacement of the femur with the negative buttress model. When the Pauwels angle was 50°, the positive buttress model had a higher displacement of the FNS and femur than the negative buttress model. Our study also showed that the von Mises stress and displacement of the internal fixation and the femur increased as the fracture angle increased. CONCLUSION: From the perspective of biomechanics, when the Pauwels angle was 30°, positive buttress was more stable to negative buttress. However, when the Pauwels angle was 50°, this advantage weakens. In our opinion, the clinical efficacy of FNS internal fixation with positive buttress may be related to the fracture angle, neck-shaft angle and alignment in the lateral view. This result needs verification in further clinical studies.

Protective Effect of Illicium Verum Extract On Vascularization In Rats With Osteoporotic Fracture.

Objective: To investigate the protective effect of Illicium verum extract on the vascularization of osteoporotic fracture in rats, and to elucidate its potential mechanism. Methods: The osteoporotic fracture model was established in ovariectomized rats. Rats were infused with 0.05 ml/kg extract in the stomach every morning. Eighteen rats are then divided into control group, model group, and Illicium verum extract group with 6 rats in each group. To observe the therapeutic effect of Illicium verum extract on osteoporotic rats. Femoral bone mineral density and elastic segment end-point load were evaluated by dual-energy x-ray absorptiometry and three-point bending test. Hematoxylin-eosin staining was used to measure the number and area of callus blood vessels. The serum levels of VEGF and NO were detected by ELISA. Moreover, the expressions of NOX2, NOX4, NRF2, p-PI3K, CyclinD1, VEGF, HIF1α, and eNOS in HUVEC were detected by Western blot. CCK8 and wound healing assay were used to detect the proliferation and migration of HUVEC. Then, the ability of HUVEC to form blood vessels was detected by tube formation assay. Results: Firstly, control group showed the normal pathomorphology and density of femoral bone, and model group showed significantly decreased bone density and consistent with bone microstructure degeneration, destruction, thinning, and fracture of bone trabecular structure vs control group, and illicium verum extract significantly increased femoral density and maximum load, increased the number and area of callus blood vessels and increased VEGF and NO levels in serum vs model group. Then, Illicium verum extract promoted the expression of NRF2, p-PI3K, CyclinD1, VEGF, HIF1α, and eNOS protein in HUVEC, inhibited the expression of NOX2 and NOX4, and enhanced the cell proliferation, migration, and angiogenesis. However, the effect was reversed by the overexpression of NRF2 and the treatment with LY294002. Conclusion: Illicium verum extract protects the vascularization of the osteoporotic fracture model in rats.

Mixture toxicity effects of chloramphenicol, thiamphenicol, florfenicol in Daphnia magna under different temperatures.

Acute toxicities of chloramphenicol (CAP), thiamphenicol (TAP), and florfenicol (FLO) and their mixtures on Daphnia magna under two representative temperatures of the aquatic environment (20 and 25 °C) have been examined. Their toxicities depicted with an order of 72-h EC50 values were as follows: CAP > FLO > TAP and CAP ≈ FLO > TAP under 20 and 25 °C, separately. Furthermore, the acute toxicity significantly increased with the rise of temperature from 20 to 25 °C in nearly all separate and mixture phenicol antibiotics. Meanwhile, the most toxic combination under two different temperatures was diverse. The nature of toxicological interactions of phenicol antibiotic mixtures was analyzed by Combination Index (CI) equation. In general, a dual synergism-antagonism effect was dominant in nearly all mixtures at both temperatures. The prediction suitability of Concentration Addition (CA), Independent Action (IA) models, and CI method was compared, suggesting that the CI equation seems to be more appropriate for predicting the toxicity values of phenicol drugs than CA and IA models. In brief, phenicol antibiotic mixtures with temperature variation may pose more significant hazards and risks to aquatic organisms; hence, the environment.

Seasonal and spatial variations in the phytoplankton community and their correlation with environmental factors in the Jinjiang River Estuary in Quanzhou, China.

The seasonal and spatial variation in the phytoplankton community structure and the environmental variables were investigated in December (the dry season) 2016 and July (the rainy season) 2017 in the Jinjiang River Estuary, China. We identified a total of 138 species of phytoplankton, which were mainly Chlorophyta, Bacillariophyta, and Cryptophyta in the dry season; however, in the rainy season, only Bacillariophyta were found. In the Jinjiang River Estuary, the species evenness and the biodiversity index were higher in the rainy season and that the species diversity was higher in the dry season. Redundancy analysis (RDA) revealed that the dominant species were statistically related to many of the environmental variables, including the water temperature (WT), pH, salinity (Sal), dissolved oxygen (DO), total phosphorus (TP), and total nitrogen (TN). Among the variables, the Sal, DO, TP, and TN had a significant influence on the dominant species distribution, and the WT and pH also affected the dominant species distribution to some extent.

An evaluation on the bioavailability of heavy metals in the sediments from a restored mangrove forest in the Jinjiang Estuary, Fujian, China.

The bioavailability of heavy metals in restored mangrove wetland sediments at the Jinjiang Estuary was assessed through acid-volatile sulfide (AVS) and simultaneously extracted metals (SEM). The results indicated that the SEM distributions were more even than the AVS in the restored regions, and the AVS acted as an important carrier for SEM. SEM-Zn was a major part (61.4-70.6%) of ∑SEM, whereas the most toxic metal, Cd, accounted for approximately 0.2%. The possible adverse effects increased in the surface and subsurface sediments (0-20 cm), with no potential bioavailability in deeper layers. This was probably due to the higher AVSs binding to heavy metal ions in the restored regions compared to the mudflat (control group). The conclusions were also similar when taking TOC concentrations into account. Mangrove wetland restoration has significant effects on the bioavailability of heavy metals in sediments. According to the thresholds for metal toxicity on benthic organisms in sediments, Pb, Cu and Ni had potential adverse effects on benthic organisms in this restored wetland.

Effects of planting patterns on heavy metals (Cd, As) in soils following mangrove wetlands restoration.

To understand how planting patterns influence As and Cd in soils, the pollution grade release risk and fractions of As and Cd in soils from Jinjiang Estuary wetland were investigated. The geoaccumulation index (Igeo) and risk assessment code (RAC) were used to identify pollution grades and reveal the potential ecological risk of trace metals, respectively. The results showed that the ratios of the acid soluble fraction of Cd in the mangrove area (∼65%) were larger than that of the control group (∼31%). The residual fraction of As in the mangrove area (∼74%) was also larger than that of the control group (∼66%). Therefore, the planting of vegetation increased the mobility of Cd and decreased the mobility of As. Variance analysis showed that the total concentrations and fraction of As and Cd significantly differed among various vegetation types and planting densities. Thus, planting patterns might influence the transformation of trace metal fractions in soil, influencing the total concentrations of As and Cd. Furthermore, mangrove reforestation improved the pollution levels of As and Cd and increased the potential release risk of Cd. The study advances current knowledge on the importance of restoring wetland vegetation, providing suggestions on feasible planting patterns.

Improving Flue Gas Mercury Removal in Waste Incinerators by Optimization of Carbon Injection Rate.

This study tested the mercury emission characteristics of six municipal solid waste incinerators (MSWIs) and recommended future mercury control via adjusting operational parameters. The results indicated that over 99% of the mercury in solid wastes ended in fly ash and flue gas, of which 3.3-66.3% was emitted to air through stack gas. Mercury in the stack gas was mainly in the form of oxidized mercury (Hg2+), the proportion (65.4-89.0%) of which was far higher than previous estimation (15%). Mercury removal efficiencies (MRE) of the tested incinerators were in the range of 33.6-95.2%. The impact of waste incineration capacity, gas flow, fly ash yield, and activated carbon (AC) injection on MRE were analyzed. We found that the MRE was significantly linearly correlated to the ratio of AC injection and fly ash yield (correlation coefficient = 0.98, significance <0.01). AC injection value is determined based on the control of dioxin emissions without considering mercury control in traditional design. To increase MRE of MSWIs, the AC injection should increase from around 100 mg·Nm-3 to 135 mg·Nm-3 for grate furnace combustor and 170 mg·Nm-3 for circulation fluidized bed combustor, so as to reach a MRE of 90%.

Mercury flows in large-scale gold production and implications for Hg pollution control.

Large-scale gold production (LSGP) is one of the five convention-related atmospheric mercury (Hg) emission sources in the Minamata Convention on Mercury. However, field experiments on Hg flows of the whole process of LSGP are limited. To identify the atmospheric Hg emission points and understand Hg emission characteristics of LSGP, Hg flows in two gold smelters were studied. Overall atmospheric Hg emissions accounted for 10%-17% of total Hg outputs and the Hg emission factors for all processes were 7.6-9.6kg/ton. There were three dominant atmospheric Hg emission points in the studied gold smelters, including the exhaust gas of the roasting process, exhaust gas from the environmental fog collection stack and exhaust gas from the converter of the refining process. Atmospheric Hg emissions from the roasting process only accounted for 16%-29% of total emissions and the rest were emitted from the refining process. The overall Hg speciation profile (gaseous elemental Hg/gaseous oxidized Hg/particulate-bound Hg) for LSGP was 34.1/57.1/8.8. The dominant Hg output byproducts included waste acid, sulfuric acid and cyanide leaching residue. Total Hg outputs from these three byproducts were 80% in smelter A and 84% in smelter B. Our study indicated that previous atmospheric Hg emissions from large-scale gold production might have been overestimated. Hg emission control in LSGP is not especially urgent in China compared to other significant emission sources (e.g., cement plants). Instead, LSGP is a potential Hg release source due to the high Hg output proportions to acid and sludge.

Review: Autologous blood transfusion drainage compared with no drainage in total knee arthroplasty: A meta-analysis and systematic review.

This is the first meta-analysis to assess the clinical efficiency, safety and potential advantages regarding the use of ABT drains compared with no drainage which is controversial in total knee arthroplasty (TKA).A comprehensive literature search was carried out in March 2015 using the PubMed, Embase, and Cochrane Library databases. A metaanalysis was carried out on two retrospective comparative studies (RCSs) and five randomized controlled trials (RCTs). The number of patients receiving homologous blood transfusion was the primary outcome of the meta-analysis; the secondary outcome measure was the mean drop in Hb level in comparison to the mean pre-operative HB level, the range of flexion of the knee joint, and infections of the wound after surgery. A total of 868 patients, who were included in two retrospective studies and five RCTs, were distributed into subgroups for the meta-analysis. This pooled data showed no benefit of ABT drainage compared no drainage in the homologous blood transfusion rate (13.05% and 16.91%, OR:0.73[0.47,1.13], Z=1.41, P=0.016; and 3.49% and 6.54%, OR: 0.50[0.12,2.01], Z=0.98,P=0.033,respectively in subgroups), Hb drop (Weight mean differences (WMD): 0.20[-0.28,0.68], Z=0.82, P=0.41; WMD:0.16[-0.41,0.55], Z=0.93, P=0.35, respectively), range of flexion of the knee joint (WMD:-0.82 [-3.35,1.70], Z =0.64,P=0.52)and wound infection (OR:0.25[0.61,10.20]; Z =1.28, p=0.2) after TKA surgery. Our findings do not recommend the routine use of postoperative ABT drainage in total knee arthroplasty. Well-designed RCTs with large sample sizes, longer term measures and extensive follow-up period should be performed in the future to update the findings of this study.

The optimization research of the multi-response problems based on the SUR.

In the optimization design of products and processes in the biological medicine, we need to consider multiple characteristics of quality simultaneously, namely multi-response problems, multi-response optimization design can improve the quality of the products effectively, and realize enormous economic benefits and so multi-response optimization design is showing a more and more important role in continuous quality improvement activities. But usually there is no specific set of input variables to make all the response variables be optimal, and the traditional multi-response surface method cannot solve the correlation problem between multi-responses and regression model problem effectively. Because we can make a better fitting model and solve the problem of the correlation between the response variables at the same time with SUR method, this thesis uses the SUR method to model the relationship between each response and control variables, and makes predictions; confirms the satisfaction function of each response and the overall satisfaction function; combines with practical problems of a company in biological medicine field named SX to conduct empirical research, this thesis confirms the optimal factor level combination with the overall satisfaction function in the end, thus solves the multi-response optimization problems.

Curculigoside Regulates Apoptosis and Oxidative Stress Against Spinal Cord Injury by Modulating the Nrf-2/NQO-1 Signaling Pathway In Vitro and In Vivo.

Spinal cord injury (SCI) is a severe neurological disorder that can lead to paralysis or death. Oxidative stress during SCI is a critical phase causing extensive nerve cell damage and apoptosis, thereby impairing spinal cord healing. Thus, a primary goal of SCI drug therapy is to mitigate oxidative stress. Curculigoside (CUR), a phenolic glucoside extracted from the dried root and rhizome of Curculigo orchioides Gaertn, possesses neuroprotective and antioxidant properties. This study aimed to investigate whether CUR effectively promotes the recovery of spinal cord tissue following SCI and elucidate its mechanism. We employed a hydrogen peroxide (H2O2)-induced PC12 cell model and an SCI rat model to observe the effects of CUR on oxidation and apoptosis. The results demonstrated that CUR significantly reduced the expression of apoptosis-related proteins (Bax and Caspase-3), Annexin V/propidium iodide (PI), and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), while increasing the expression of the anti-apoptotic protein Bcl-2. Moreover, CUR effectively enhanced levels of antioxidants (glutathione [GSH)] and decreased reactive oxygen species (ROS) in vitro. Furthermore, CUR facilitated functional recovery through its anti-apoptotic and anti-oxidative stress effects on spinal cord tissues in SCI rats. These effects were mediated via the Nrf2/NQO1 signaling pathway. Therefore, our study showed that CUR acted as an anti-apoptotic and anti-oxidative stress agent, inhibiting astrocyte activation and promoting neuronal reconstruction and functional recovery. These findings may contribute significantly to the development of SCI treatments and advance the field of SCI drug therapy.

Transplantation of MiR-28-5p-Modified BMSCs Promotes Functional Recovery After Spinal Cord Injury.

Traumatic spinal cord injury (TSCI) is a prevalent central nervous system condition that imposes a significant burden on both families and society, affecting more than 2 million people worldwide. Recently, there has been increasing interest in bone marrow mesenchymal stem cell (BMSC) transplantation as a promising treatment for spinal cord injury (SCI) due to their accessibility and low immunogenicity. However, the mere transplantation of BMSCs has limited capacity to directly participate in the repair of host spinal cord nerve function. MiR-28-5p, identified as a key differentially expressed miRNA in spinal cord ischemia-reperfusion injury, exhibits differential expression and regulation in various neurological diseases. Nevertheless, its involvement in this process and its specific regulatory mechanisms in SCI remain unclear. Therefore, this study aimed to investigate the potential mechanisms through which miR-28-5p promotes the neuronal differentiation of BMSCs both in vivo and in vitro. Our results indicate that miR-28-5p may directly target Notch1, thereby facilitating the neuronal differentiation of BMSCs in vitro. Furthermore, the transplantation of lentivirus-mediated miR-28-5p-overexpressed BMSCs into SCI rats effectively improved footprint tests and Basso, Beattie, and Bresnahan (BBB) scores, ameliorated histological morphology (hematoxylin-eosin [HE] and Nissl staining), promoted axonal regeneration (MAP2 and growth-associated protein 43 [GAP43]), and facilitated axonal remyelination (myelin basic protein [MBP]). These findings may suggest that miR-28-5p-modified BMSCs could serve as a therapeutic target to enhance the behavioral and neurological recovery of SCI rats.

Regression of a large prolapsed lumbar disc herniation achieved by conservative treatment: A case report and literature review.

A common spinal condition known as lumbar disc herniation (LDH) can result in radicular and low back discomfort. A 27-year-old man was admitted to our hospital with a 6-year history of persistent low back pain, and his low back pain had recurred with radiation to his lower extremities over the last two months. An extensive right-sided paracentral disc herniation in the L5/S1 intervertebral region, which compressed the nerve root, was discovered by magnetic resonance imaging (MRI) of his lumbar spine. After receiving conservative treatment, the patient reported that his lower back discomfort and neurogenic claudication had gradually subsided after 4 months. After one year, a follow-up MRI showed that the massive, prolapsed disc herniation at the L5/S1 level had totally disappeared. The sagittal protrusion length of the L5/S1 intervertebral disc shrank from 12.35 mm to 3.49 mm. However, there remained a chance of vertebral height loss. During the course of treatment, the height of the L5/S1 intervertebral space was still slightly reduced. The intervertebral space height declined from 7.705 mm to 7.201 mm after one year of treatment. The current case and a review of the literature demonstrate that LDH can decrease with conservative therapy over a short period of time. We stress the effectiveness of conservative treatment in very select LDH cases that lack a clear surgical justification.

Effects of natural nanoparticles on the acute toxicity, chronic effect, and oxidative stress response of phenicol antibiotics in Daphnia magna.

Natural nanoparticles (NNP) are ubiquitous in natural water and can interact with other contaminants, causing ecotoxic effects on aquatic nontarget organisms. However, the impact of NNPs on the ecotoxicity of antibiotics remains largely unknown. This work investigated the acute toxicity, chronic effect, and oxidative response and damage in Daphnia magna co-exposed to phenicol antibiotics (chloramphenicol, thiamphenicol) and different concentrations of NNPs (10 mg/L: environmentally relevant concentration; 100 mg/L: a high concentration that caused no apparent immobilization in D. magna). The results showed that the acute toxicity of chloramphenicol was increased by 10 mg/L NNPs but decreased by 100 mg/L NNPs; both concentrations of NNPs increased and decreased acute toxicities of thiamphenicol and chloramphenicol + thiamphenicol treatments, respectively. After long-term exposure, phenicol antibiotics (1 µg/L) and NNP (10 mg/L) mixtures in environmentally relevant concentrations significantly affected the reproduction of D. magna but did not influence their growth. The catalase activity, reduced glutathione level, and malonaldehyde content in D. magna also varied with the NNPs concentrations. Notably, the lowest concentration of thiamphenicol and chloramphenicol + thiamphenicol combined with NNPs significantly increased the malondialdehyde content in D. magna compared with the control, indicating membrane lipid peroxidation occurred in daphnids. This study suggests that the toxic effects of contaminants and NNPs on aquatic organisms should be considered thoroughly to avoid underestimating the hazard of these pollutants in the actual aquatic environment.

Tauroursodeoxycholic Acid Inhibited Apoptosis and Oxidative Stress in H2O2-Induced BMSC Death via Modulating the Nrf-2 Signaling Pathway: the Therapeutic Implications in a Rat Model of Spinal Cord Injury.

Spinal cord injury (SCI) is a prevalent and significant injury to the central nervous system, resulting in severe consequences. This injury is characterized by motor, sensory, and excretory dysfunctions below the affected spinal segment. Transplantation of bone marrow mesenchymal stem cells (BMSCs) has emerged as a potential treatment for SCI. However, the low survival as well as the differentiation rates of BMSCs within the spinal cord microenvironment significantly limit their therapeutic efficiency. Tauroursodeoxycholic acid (TUDCA), an active ingredient found in bear bile, has demonstrated its neuroprotective, antioxidant, and antiapoptotic effects on SCI. Thus, the present study was aimed to study the possible benefits of combining TUDCA with BMSC transplantation using an animal model of SCI. The results showed that TUDCA significantly enhanced BMSC viability and reduced apoptosis (assessed by Annexin V-FITC, TUNEL, Bax, Bcl-2, and Caspase-3) as well as oxidative stress (assessed by ROS, GSH, SOD, and MDA) both in vitro and in vivo. Additionally, TUDCA accelerated tissue regeneration (assessed by HE, Nissl, MAP2, MBP, TUJ1, and GFAP) and improved functional recovery (assessed by BBB score) following BMSC transplantation in SCI. These effects were mediated via the Nrf-2 signaling pathway, as evidenced by the upregulation of Nrf-2, NQO-1, and HO-1 expression levels. Overall, these results indicate that TUDCA could serve as a valuable adjunct to BMSC transplantation therapy for SCI, potentially enhancing its therapeutic efficacy.

Crochet Hook Technique for Arthroscopic Anterior Talofibular Ligament Repair: Technique Note.

Ankle sprains can lead to chronic lateral ankle instability caused by an injured anterior talofibular ligament (ATFL), and surgery is often required when conservative treatments fail. BROSTROM surgery is considered the gold standard and has a definite curative effect. Advancements in arthroscopic surgery and improvements in implanted anchors have led to an increase in ATFL repairs using arthroscopic surgery. Arthroscopic AFTL repair is less invasive, and patients could experience faster recovery compared to open AFTL repair. To simplify the complicated suture-passing processes in arthroscopic AFTL repair, we developed a crochet hook and loop wire technique, which is described in this paper.

Circular RNA circ_0000423 regulates cartilage ECM synthesis via circ_0000423/miRNA-27b-3p/MMP-13 axis in osteoarthritis.

Circular RNA (circRNA) is related to many human diseases including osteoarthritis (OA). Our research purpose was to show that functional circRNAs have a role in the pathogenesis of OA, while also identifying potential circRNA that bind to miRNA-27b-3p. Microarray analysis was used to evaluate the expression of CircRNA in OA and normal cartilage. The role and functional mechanism of Circ_0000423 up-regulation were detected in OA and verified in vitro and in vivo. RNA transfection, qRT-PCR, Western blot analysis, immunofluorescence, and dual-luciferase assays were used to investigate the interaction between Circ_0000423 and miRNA-27b-3p in vitro. The roles of Circ_0000423 were discussed in vivo. Our results discovered 11 down-regulated circRNAs and 101 up-regulated circRNAs between control and OA tissues, and confirmed that Circ_0000423 an increase significantly in OA tissues by evaluating the different circRNAs expressions. Meanwhile, luciferase analysis confirmed Circ_0000423 can be directly targeted by miRNA-27b-3p and act as a miRNA-27b-3p sponge. Circ_0000423 can influence MMP-13 and collagen II expression by targeting miRNA-27b-3p expression as ceRNA in OA. Furthermore, AAV-shRNA-Circ 0000423 intra-articular injection slows the progression of OA by decreasing articular cartilage destruction and erosion, joint surface fibrosis, osteophyte formation, MMP-13 expression, and increasing collagen II expression in the articular cartilage of ACLT-induced OA mice model. These findings confirmed that the Circ_0000423-miRNA-27b-3p-MMP-13 axis could affect the pathogenesis of OA which might lead to a novel target for diagnostic molecular biological indicators and potential OA treatments.

Hsa_circ_0001485 promoted osteogenic differentiation by targeting BMPR2 to activate the TGFß-BMP pathway.

BACKGROUND: Circular RNAs (circRNAs) are a new type of stable noncoding RNA and have been proven to play a crucial role in osteoporosis. This study explored the role and mechanism of hsa_circ_0001485 in osteogenic differentiation. METHODS: Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis and Gene Ontology (GO) enrichment analysis were performed according to the previous sequencing data in human bone marrow mesenchymal stem cells (BMSC) before and after the induction of osteogenic differentiation on the differentially expressed circRNAs, to screen out signaling pathways associated with osteogenic differentiation. The hFOB 1.19 cells were used to verify the function and mechanism of specific circRNAs in osteogenic differentiation. Additionally, small interfering fragments and overexpression plasmids were used to determine the role of specific circRNAs during osteogenic differentiation. Furthermore, pull-down experiments and mass spectrometry were performed to determine the proteins that bind to specific circRNAs. RESULTS: The KEGG and GO enrichment analyses showed that the TGFß-BMP signaling pathway was related to the osteogenic differentiation process, and four circRNAs were associated with the pathway. The quantitative polymerase chain reaction analysis revealed that hsa_circ_0001485 expression was increased during the osteogenic differentiation process of BMSCs. Knockdown of hsa_circ_0001485 suppressed the activity of the alkaline phosphatase enzyme and the expression of RUNX2, osteopontin, and osteocalcin in the osteogenic hFOB 1.19 cells, whereas overexpression of hsa_circ_0001485 promoted their expression. Additionally, we found that hsa_circ_0001485 and BMPR2 targeted binding to activate the TGFß-BMP signaling pathway and promoted osteogenic differentiation through mass spectrometry analysis. CONCLUSION: This study demonstrates that hsa_circ_0001485 is highly expressed in the osteogenic hFOB 1.19 cells, which activate the TGFß-BMP pathway through targeted binding of BMPR2, and plays a positive role in regulating osteogenic differentiation.

Do we have to pursue complete reduction after PVA in osteoporotic vertebral compression fractures: a finite element analysis.

BACKGROUND: Consensus regarding the optimal amount of bone cement and vertebral height in the treatment of osteoporotic vertebral compression fractures (OVCFs) is lacking. Our purpose was to explore the optimal amount of bone cement and vertebral height in OVCF after percutaneous vertebral augmentation (PVA). METHODS: A three-dimensional finite element model of the L1-L3 segments was constructed from CT scans of aging osteoporosis patients. Four different postoperative vertebral height models were simulated according to Genant semiquantitative grades 0, 1, 2, and 3. The volume of bone cement filling ranged from 3 ml to 6 ml. These models evaluated the von Mises stress of injured vertebral bodies, adjacent vertebral bodies and intervertebral discs under flexion, extension, left flexion, and right flexion after PVA. RESULTS: When the bone cement content was held constant, as the height of the vertebral body decreased, the stress of the L2 vertebral body decreased during left flexion and right flexion, but the stress of the L2 vertebral body increased and decreased during flexion and extension. As the height of the vertebral body decreased, the stress of the L1-L2 intervertebral disc increased. There was no significant change in the stress of other adjacent vertebrae or intervertebral discs. When the Genant grade was 0, 1, or 2 (3 ml and 4 ml), the stress of the overall vertebral body was closest to normal. CONCLUSIONS: When the height of the vertebral body is restored to the same height, a bone cement filling volume of 3 ml to 6 ml is suitable and will not produce a significant change in the stress of the vertebral body or adjacent vertebral body. As vertebral body height was lost, it may promote the degeneration of the intervertebral disc above the injury vertebrae after PVA. It is appropriate for the height of the vertebral body to return to Genant grade 0 or Genant grade 1 after surgery. When the height of the vertebral body has Genant grade 2 status, it was best to use 3 ml to 4 ml of bone cement filling. Therefore, when treating OVCFs, clinicians do not need to pursue complete reduction of the vertebral body. It is also important to verify the biomechanics results in clinical studies.