The complete chloroplast genome of Oxytropis ochrocephala Bunge 1874 (Fabaceae) and its phylogenetic analysis.

This study presents the first-ever complete chloroplast (cp) genome sequence of Oxytropis ochrocephala Bunge 1874, a member of the Fabaceae family. The cp genome spans 126,996 base pairs and includes 109 genes, comprising 76 protein-coding genes, 29 tRNA genes, and four rRNA genes. Notably, the genome lacks an inverted repeat (IR) region. Additionally, we constructed phylogenetic trees for 34 species within Trib. Galegeae, employing both maximum likelihood (ML) and Bayesian inference (BI) methods. These analyses robustly support the monophyly of the Oxytropis species, evidenced by high bootstrap values (BP = 100) and posterior probabilities (PP = 1). Within this clade, O. ochrocephala exhibits a sister relationship with other Oxytropis species. Our findings provide valuable insights into the genetic makeup and evolutionary relationships of O. ochrocephala within the Galegeae tribe.

Melatonin-encapsuled silk fibroin electrospun nanofibers promote vascularized bone regeneration through regulation of osteogenesis-angiogenesis coupling.

The repair of critical-sized bone defects poses a significant challenge due to the absence of periosteum, which plays a crucial role in coordinating the processes of osteogenesis and vascularization during bone healing. Herein, we hypothesized that melatonin-encapsuled silk Fibronin electrospun nanofibers (SF@MT) could provide intrinsic induction of both osteogenesis and angiogenesis, thereby promoting vascularized bone regeneration. The sustained release of melatonin from the SF@MT nanofibers resulted in favorable biocompatibility and superior osteogenic induction of bone marrow mesenchymal stem cells (BMMSCs). Interestingly, melatonin promoted the migration and tube formation of human umbilical vein endothelial cells (HUVECs) in a BMMSC-dependent manner, potentially through the upregulation of vascular endothelial growth factor (VEGFA) expression in SF@MT-cultured BMMSCs. SF@MT nanofibers enhanced the BMMSC-mediated angiogenesis by activating the PI3K/Akt signaling pathway. In vivo experiments indicated that the implantation of SF@MT nanofibers into rat critical-sized calvarial defects significantly enhances the production of bone matrix and the development of new blood vessels, leading to an accelerated process of vascularized bone regeneration. Consequently, the utilization of melatonin-encapsulated silk Fibronin electrospun nanofibers shows great promise as a potential solution for artificial periosteum, with the potential to regulate the coupling of osteogenesis and angiogenesis in critical-sized bone defect repair.

Melatonin rescues the mitochondrial function of bone marrow-derived mesenchymal stem cells and improves the repair of osteoporotic bone defect in ovariectomized rats.

Osteoporotic bone defects, a severe complication of osteoporosis, are distinguished by a delayed bone healing process and poor repair quality. While bone marrow-derived mesenchymal stem cells (BMMSCs) are the primary origin of bone-forming osteoblasts, their mitochondrial function is impaired, leading to inadequate bone regeneration in osteoporotic patients. Melatonin is well-known for its antioxidant properties and regulation on bone metabolism. The present study postulated that melatonin has the potential to enhance the repair of osteoporotic bone defects by restoring the mitochondrial function of BMMSCs. In vitro administration of melatonin at varying concentrations (0.01, 1, and 100 µM) demonstrated a significant dose-dependent improvement in the mitochondrial function of BMMSCs obtained from ovariectomized rats (OVX-BMMSCs), as indicated by an elevation in mitochondrial membrane potential, adenosine triphosphate synthesis and expression of mitochondrial respiratory chain factors. Melatonin reduced the level of mitochondrial superoxide by activating the silent information regulator type 1 (SIRT1) and its downstream antioxidant enzymes, particularly superoxide dismutase 2 (SOD2). The protective effects of melatonin were found to be nullified upon silencing of Sirt1 or Sod2, underscoring the crucial role of the SIRT1-SOD2 axis in the melatonin-induced enhancement of mitochondrial energy metabolism in OVX-BMMSCs. To achieve a sustained and localized release of melatonin, silk fibroin scaffolds loaded with melatonin (SF@MT) were fabricated. The study involved the surgical creation of bilateral femur defects in OVX rats, followed by the implantation of SF@MT scaffolds. The results indicated that the application of melatonin partially restored the mitochondrial energy metabolism and osteogenic differentiation of OVX-BMMSCs by reinstating mitochondrial redox homeostasis. These findings suggest that the localized administration of melatonin through bone implants holds potential as a therapeutic approach for addressing osteoporotic bone defects.

Melatonin-loaded self-healing hydrogel targets mitochondrial energy metabolism and promotes annulus fibrosus regeneration.

Intervertebral disc (IVD) herniation is a major cause of chronic low back pain and disability. The current nucleus pulposus (NP) discectomy effectively relieves pain symptoms, but the annulus fibrosus (AF) defects are left unrepaired. Tissue engineering approaches show promise in treating AF injury and IVD degeneration; however, the presence of an inflammatory milieu at the injury site hinders the mitochondrial energy metabolism of AF cells, resulting in a lack of AF regeneration. In this study, we fabricated a dynamic self-healing hydrogel loaded with melatonin (an endocrine hormone well-known for its antioxidant and anti-inflammatory properties) and investigate whether melatonin-loaded hydrogel could promote AF defect repair by rescuing the matrix synthesis and energy metabolism of AF cells. The protective effects of melatonin on matrix components (e.g. type I and II collagen and aggrecan) in AF cells were observed in the presence of interleukin (IL)-1ß. Additionally, melatonin was found to activate the nuclear factor erythroid 2-related factor signaling pathway, thereby safeguarding the mitochondrial function of AF cells from IL-1ß, as evidenced by the increased level of adenosine triphosphate, mitochondrial membrane potential, and respiratory chain factor expression. The incorporation of melatonin into a self-healing hydrogel based on thiolated gelatin and ß-cyclodextrin was proposed as a means of promoting AF regeneration. The successful implantation of melatonin-loaded hydrogel has been shown to facilitate in situ regeneration of AF tissue, thereby impeding IVD degeneration by preserving the hydration of nucleus pulposus in a rat box-cut IVD defect model. These findings offer compelling evidence that the development of a melatonin-loaded dynamic self-healing hydrogel can promote the mitochondrial functions of AF cells and represents a promising strategy for IVD regeneration.

Incorporation of kartogenin and silk fibroin scaffolds promotes rat articular cartilage regeneration through enhancement of antioxidant functions.

Treating articular cartilage defects in patients remains a challenging task due to the absence of blood vessels within the cartilage tissue. The regenerative potential is further compromised by an imbalance between anabolism and catabolism, induced by elevated levels of reactive oxygen species. However, the advent of tissue engineering introduces a promising strategy for cartilage regeneration, offering viable solutions such as mechanical support and controlled release of chondrogenic molecules or cytokines. In this study, we developed an antioxidant scaffold by incorporating natural silk fibroin (SF) and kartogenin (KGN)-loaded liposomes (SF-Lipo@KGN). The scaffold demonstrated appropriate pore size, connectivity, and water absorption and the sustained release of KGN was achieved through the encapsulation of liposomes. In vitro experiments revealed that the SF-Lipo@KGN scaffolds exhibited excellent biocompatibility, as evidenced by enhanced cell adhesion, migration, and proliferation of chondrocytes. The SF-Lipo@KGN scaffolds were found to stimulate cartilage matrix synthesis through the activation of the nuclear factor erythroid-2-related factor 2/heme oxygenase-1 antioxidant signaling pathway. In vivo experiments demonstrated the effective promotion of articular cartilage regeneration by the SF-Lipo@KGN scaffolds, which enhanced extracellular matrix anabolism and restored the intrinsic redox homeostasis. Overall, this study successfully developed biomimetic KGN-loaded scaffolds that restore cartilage redox homeostasis, indicating promising prospects for cartilage tissue engineering.

Selenium-modified bone cement promotes osteoporotic bone defect repair in ovariectomized rats by restoring GPx1-mediated mitochondrial antioxidant functions.

Over-accumulation of reactive oxygen species (ROS) causes mitochondrial dysfunction and impairs the osteogenic potential of bone marrow-derived mesenchymal stem cells (BMMSCs). Selenium (Se) protects BMMSCs from oxidative stress-induced damage; however, it is unknown whether Se supplementation can promote the repair of osteoporotic bone defects by rescuing the impaired osteogenic potential of osteoporotic BMMSCs (OP-BMMSCs). In vitro treatment with sodium selenite (Na2SeO3) successfully improved the osteogenic differentiation of OP-BMMSCs, as demonstrated by increased matrix mineralization and up-regulated osteogenic genes expression. More importantly, Na2SeO3 restored the impaired mitochondrial functions of OP-BMMSCs, significantly up-regulated glutathione peroxidase 1 (GPx1) expression and attenuated the intracellular ROS and mitochondrial superoxide. Silencing of Gpx1 completely abrogated the protective effects of Na2SeO3 on mitochondrial functions of OP-BMMSCs, suggesting the important role of GPx1 in protecting OP-BMMSCs from oxidative stress. We further fabricated Se-modified bone cement based on silk fibroin and calcium phosphate cement (SF/CPC). After 8 weeks of implantation, Se-modified bone cement significantly promoted bone defect repair, evidenced by the increased new bone tissue formation and enhanced GPx1 expression in ovariectomized rats. These findings revealed that Se supplementation rescued mitochondrial functions of OP-BMMSCs through activation of the GPx1-mediated antioxidant pathway, and more importantly, supplementation with Se in SF/CPC accelerated bone regeneration in ovariectomized rats, representing a novel strategy for treating osteoporotic bone fractures or defects.

Effect of the intermediate pedicle screws and their insertion depth on sagittal balance and functional outcomes of lumbar fracture.

Objective: This study aimed to examine the effect of the intermediate pedicle screws and their insertion depth on sagittal balance and functional outcomes of lumbar fracture. Methods: This study reviewed 1,123 patients with lumbar fractures between January 2015 and June 2019, and 97 patients were ultimately enrolled in this study: Group A: 32 patients in the four-pedicle screws fixation group; Group B: 28 patients in the six-pedicle screws fixation with long intermediate pedicle screws group; Group C: 37 patients in the six-pedicle screws fixation with short intermediate pedicle screws group. The radiographic outcomes were assessed with lumbar lordosis (LL), segmental lordosis (SL), fractured vertebral lordosis (FL), sacral slope (SS), pelvic incidence (PI), and pelvic tilt (PT). The visual analog scale (VAS) and the Oswestry disability index (ODI) scores were used for assessing functional outcomes. Results: The PI, PT, and SS showed no significant differences between the three groups (P > 0.05). Compared with Group A, Groups B and C showed better FL, SL, and LL 1 month after operation (5.96 ± 1.67/4.81 ± 1.49 vs. 8.78 ± 2.90, 24.39 ± 3.80/23.70 ± 4.10 vs. 20.09 ± 3.33, 39.07 ± 3.61/39.51 ± 3.23 vs. 36.41 ± 3.11, P < 0.05) and at final follow-up (8.75 ± 1.40/6.78 ± 1.70 vs. 11.31 ± 2.61, 22.11 ± 3.39/23.70 ± 4.10 vs. 17.66 ± 2.60, 38.04 ± 3.49/39.51 ± 3.23 vs. 35.41 ± 3.11, P < 0.05). The FL of Group C were significantly better than those of Group B 1 month after operation (4.81 ± 1.49 vs. 5.96 ± 1.67, P < 0.05) and at final follow-up (6.78 ± 1.70 vs. 8.75 ± 1.40, P < 0.05). No significant differences in VAS and ODI were found between Group A and Group B (P > 0.05). There were also no significant differences in VAS and ODI between Group A and Group C (P > 0.05). However, The VAS and ODI of Group C showed better than Group B 1 month after operation (3.05 ± 0.70 vs. 3.54 ± 0.79, 17.65 ± 3.41 vs. 19.71 ± 2.35, P < 0.05) and at final follow-up (2.19 ± 0.46 vs. 2.57 ± 0.57, 13.81 ± 2.20 vs. 15.57 ± 1.73, P < 0.05). Conclusions: Both four-pedicle screw fixation and six-pedicle screw fixation were effective in treating lumbar fracture. However, six-pedicle screw fixation with short intermediate pedicle screws showed better radiographic and functional outcomes after surgery. Therefore, we recommend six-pedicle screws fixation with short intermediate pedicle screws for the long-term recovery of sagittal balance and function.

Comparison of Efficacy of Percutaneous Vertebroplasty versus Percutaneous Kyphoplasty in the Treatment of Osteoporotic Vertebral Asymmetric Compression Fracture.

BACKGROUND: This study aims to compare the clinical efficacy of percutaneous vertebroplasty (PVP) and percutaneous kyphoplasty (PKP) in the treatment of osteoporotic vertebral asymmetric compression fracture (OVACF). METHODS: This study retrospectively reviewed the patients who were diagnosed with OVACF between September 2015 and July 2019. Forty-one patients received PVP surgery (group A), and 44 patients received PKP surgery (group B). The visual analog scale, Oswestry Disability Index, scoliosis angle (SA), height of long side, height of short side (HS), and lateral height difference (LHD) before operation and 3 days and 1 year after operation were compared between both groups. The operation time, fluoroscopic time, hospital stay, cement volume, and complications were also compared between both groups. RESULTS: The visual analog scale and Oswestry Disability Index differed significantly between the groups 1 year after operation (P < 0.05). Compared with the preoperative results, there were significant differences in SA, height of long side, HS, and LHD 3 days and 1 year after operation (P < 0.05). Compared with group A, group B showed significantly better in SA, HS, and LHD in group B 3 days and 1 year after operation (P < 0.05). More patients in group A suffered cement leakage and scoliosis than group B after operation (P < 0.05). CONCLUSIONS: In our study, PVP and PKP are both effective in the treatment of OVACF, but PKP surgery had better long-term clinical efficacy.

Comparison of 3-level anterior cervical discectomy and fusion and open-door laminoplasty in cervical sagittal balance: A retrospective study.

Objective: To compare the clinical efficacy and radiological outcomes of 3-level anterior cervical discectomy and fusion (ACDF) and open-door laminoplasty (LP). Methods: A total of 74 patients from January 2017 to January 2020 were enrolled in this retrospective study. There were two groups. Group A (30 cases) received 3-level ACDF, while Group B (44 cases) received open-door LP. Clinical evaluation included perioperative parameters, Neck Disability Index (NDI), and Japanese Orthopaedic Association (JOA) scores. Radiological evaluation included cervical curve depth (CCD), C2-7 angle, C2-7 sagittal vertical axis (cSVA), C7 slope (C7S), and T1 slope (T1S). Results: Perioperative parameters such as blood loss, drainage volume after surgery, and hospital stay of patients in Group A were significantly less than those in Group B (P < .001). NDI scores decreased and JOA scores increased significantly after surgery in both groups (P < .05). There was a significant difference in both scores postoperatively and at 1 month after surgery between the two groups (P < .05). CCD and C2-7 angle of Group A increased significantly postoperatively at 1 month after surgery and at final follow-up (FFU) (P < .05). There was a significant difference in CCD and the C2-7 angle between the two groups postoperatively at 1 month after surgery and at FFU (P < .05). T1S increased significantly in Group A postoperatively and at 1 month after surgery (P < .05). Conclusion: 3-level ACDF and open-door LP achieved favorable clinical outcomes and ACDF benefited patients in the early stage of rehabilitation. Compared with open-door LP, 3-level ACDF had advantages of reconstructing cervical lordosis with increased CCD and C2-7 angle.

Kyphoplasty for thoracic and lumbar fractures with an intravertebral vacuum phenomenon in ankylosing spondylitis patients.

Background: Intravertebral vacuum phenomenon (IVP) is a special sign after vertebral fractures, which is common in patients with ankylosing spondylitis (AS) and may indicate pseudarthrosis and bone nonunion that lead to spinal instability. The objective of this study is to evaluate the efficacy and safety of kyphoplasty (KP) in treating such types of vertebral fractures with AS. Methods: Sixteen patients with AS suffering from thoracic or lumbar fractures with IVP received KP from 2015 to 2020 and were monitored for more than 1 year. The visual analog scale (VAS) score was used to evaluate back pain relief. The Oswestry Disability Index (ODI) questionnaire was used to assess the improvement of the patients' living quality. The anterior and middle vertebral height restoration ratio (AVH, MVH) and the kyphotic angle (KA) were used to evaluate the radiographic results. Results: The mean follow-up period was 20.8 months (12-28 months). The VAS and ODI significantly reduced at 3 days, 3 months after surgery, and at the last follow-up compared with the preoperative outcomes (p < 0.05). The AVH and MVH were significantly increased compared with the preoperative outcomes (p < 0.05). There was a significant correction in the KA between pre- and postoperative assessments (p < 0.05). Asymptomatic intradiscal polymethylmethacrylate (PMMA) cement leakage was found in two patients. Conclusions: For thoracic or lumbar fractures with IVP in AS patients, KP may be safe and effective, which achieves pain relief and satisfying functional improvement, restores the anterior and middle height, and corrects the kyphotic angle of the fractured vertebra.

Influence of Different Surgical Timing after Percutaneous Kyphoplasty for Osteoporotic Vertebral Compression Fractures: A Retrospective Study.

Background: A large number of people suffer from osteoporotic vertebral compression fractures (OVCFs) worldwide. Percutaneous kyphoplasty (PKP), considered a minimally invasive surgery, has been widely used to treat OVCFs and achieves satisfactory outcomes. However, the surgical timing of PKP is still under discussion. Methods: A total of 149 patients were enrolled in the study and were divided into 3 groups according to different surgical timing. Group A (n = 52) included patients who required emergency surgery. Group B (n = 50) included patients who required surgery around a week after injury. Group C (n = 47) included patients who required surgery a month or more after injury. Characteristics of patients and radiological images were recorded. The Visual Analog Scale (VAS) scores and the Oswestry Disability Index (ODI) scores were analyzed before, 1 day, 1 month, and 6 months after surgery. In addition, compression rates of anterior vertebral height (AVH) were calculated and the kyphosis Cobb angle was measured before and after surgery. Results: There was a significant difference in the VAS and ODI scores between the three groups at 1 day, 1 month, and 6 months after PKP. The VAS and ODI scores of Group C were higher than those of Groups A and B. The AVH compression rates of Group C were significantly higher than those of Groups A and B postoperatively 1 day, 1 month, and 6 months. The kyphosis Cobb angles in Group C was significantly larger than those in Groups A and B at 1 day and 1 month after PKP. Conclusions: Emergency PKP showed more advantages in both clinical and radiological outcomes. We recommend early PKP for the treatment of OVCFs.

Identification of genes involved in drought tolerance in seedlings of the desert grass, Psammochloa villosa (Poaceae), based on full-length isoform sequencing and de novo assembly from short reads.

Psammochloa villosa is a perennial herbaceous plant that is dominant within arid regions of the Inner Mongolian Plateau and the Qinghai-Tibet Plateau in China, where it is an endemic species and exhibits strong drought tolerance and wind resistance. To study drought tolerance in P. villosa and determine its molecular basis, we simulated high and moderate drought stress in a controlled environment and then analyzed transcriptome sequences by combining long-read sequences from a representative, wild-grown individual with short reads from the treatment groups. We obtained 184,076 high-quality isoforms as a reference and 168,650 genes (91.6%), which we were able to annotate according to public databases. Ultimately, we obtained 119,005 unigenes representing the transcriptome of P. villosa under drought stress and, among these, we identified 3089 differentially expressed genes and 1484 transcription factors. Physiologically, P. villosa that was exposed to high and moderate drought stress had reduced germination rates and shorter buds but generated more chlorophyll, which is atypical under drought stress and possibly reflects an adaptation of these plants to their arid environment. We inferred that significantly upregulated genes were annotated as 'Chlorophyll a-b binding protein' and 'Light-harvesting chlorophyll-protein' among drought and control groups. Broadly, our analyses revealed that drought stress triggered many genome-level responses, especially related to mitigation of radical oxygen species (ROS), which increase in concentration under drought stress. In particular, in the high drought stress group compared with the control, GO enrichment analysis revealed a significant enrichment of upregulated genes (n = 10) involved in mitigation of oxidative stress. Similarly, using KEGG we found significant enrichment of genes in the phenylpropanoid biosynthesis pathway (11 genes), which yields phenols that scavenge ROS. We also inferred that many genes involved in metabolism of arginine and proline, which may serve as both scavengers of ROS and osmoprotectants that interact with stress response genes based on our protein-protein interaction network analysis. We verified the relative expression levels of eight genes associated with mitigation of ROS, DNA repair, and transmembrane transporter activity using qRT-PCR, and the results were consistent with our inferences from transcriptomes. This study provides insights into the genomic and physiological basis of drought tolerance in P. villosa and represents a resource for development of the species as a forage crop via molecular breeding within arid lands.

Effects of distribution of bone cement on clinical efficacy and secondary fracture after percutaneous kyphoplasty for osteoporotic vertebral compression fractures.

Objective: To investigate the effect of bilateral bone cement distribution on the clinical efficacy of percutaneous kyphoplasty (PKP) in the treatment of osteoporotic vertebral compression fracture (OVCF). Methods: According to strict inclusion and exclusion criteria, 109 cases of OVCF patients treated with bipedicular PKP were included in this study from August 2018 to July 2020. According to the distribution morphology of bilateral bone cement in vertebral body, patients were divided into 3 groups, including Group A (n = 44): bilateral diffuse type; Group B (n = 31): bilateral dense type; Group C (n = 34): mixed type. To assess the clinical and radiographic efficacy of the surgery, the visual analogue scale (VAS) score, Oswestry disability index (ODI) score, anterior vertebral height (AVH), anterior vertebral height ratio (AVHR) and local kyphotic angle (LKA) were recorded at preoperatively, 2 days after surgery and 1 year after surgery. Results: Compared with the preoperative recorded value, the VAS score, ODI score, AVH, AVHR and LKA of the three groups were significantly improved at 2 days after surgery and 1 year after surgery (p < 0.05). At 1 year after surgery, the VAS score of Group A was better than that of groups B and C (p < 0.05), and there were significantly differences in ODI score, AVH, and LKA between Group A and Group B (p < 0.05). Compared with other bone cement distribution patterns, the incidence of recompression in bilateral diffuse bone cement distribution pattern was lower (p < 0.05). Conclusion: In the mid-term follow-up of patients undergoing bipedicular PKP, diffuse and symmetrical distribution of bone cement can obtain better clinical improvement and lower the incidence of secondary compression.