Mitochondria-engine with self-regulation to restore degenerated intervertebral disc cells via bioenergetic robust hydrogel design.

Previous studies have confirmed that intervertebral disc degeneration (IDD) is closely associated with inflammation-induced reactive oxygen species (ROS) and resultant cell mitochondrial membrane potential (MMP) decline. Clearance of ROS in an inflammatory environment is essential for breaking the vicious cycle of MMP decline. Additionally, re-energizing the mitochondria damaged in the inflammatory milieu to restore their function, is equally important. Herein, we proposed an interesting concept of mitochondrion-engine equipped with coolant, which enables first to "cool-down" the inflammatory environment, next to restore the MMP, finally to allow cells to regain normal energy metabolism through materials design. As such, we developed a multi-functional composite composed of a reactive oxygen species (ROS)-responsive sodium alginate/gelatin hydrogel infused into a rigid 3D-printed thermoplastic polyurethane (TPU) scaffold. The TPU scaffold was coated with conductive polypyrrole (PPy) to electrophoretically deposit l-arginine, which could upregulate the Mammalian target of rapamycin (mTOR) pathway, thus increasing MMP and energy metabolism to stimulate extracellular matrix synthesis for IVD repair. While the ROS-responsive hydrogel acting as the "mito-engine coolant" could scavenge the excessive ROS to create a favorable environment for IVD cells recovery. Demonstrated by in vitro and in vivo evaluations, the mito-engine system markedly promoted the proliferation and collagen synthesis of nucleus pulposus cells while enhancing the mitochondrial respiration and MMP under oxidative stress. Radiological and histological assessments in vivo revealed the efficacy of this system in IVD repair. This unique bioinspired design integrated biomaterial science with mitochondrial biology, presents a promising paradigm for IDD treatment.

A Comprehensive Review of Image Line Segment Detection and Description: Taxonomies, Comparisons, and Challenges.

An image line segment is a fundamental low-level visual feature that delineates straight, slender, and uninterrupted portionsof objects and scenarios within images. Detection and description of line segments lay the basis for numerous vision tasks. Althoughmany studies have aimed to detect and describe line segments, a comprehensive review is lacking, obstructing their progress. This studyfills the gap by comprehensively reviewing related studies on detecting and describing two-dimensional image line segments to provideresearchers with an overall picture and deep understanding. Based on their mechanisms, two taxonomies for line segment detectionand description are presented to introduce, analyze, and summarize these studies, facilitating researchers to learn about them quicklyand extensively. The key issues, core ideas, advantages and disadvantages of existing methods, and their potential applications for eachcategory are analyzed and summarized, including previously unknown findings. The challenges in existing methods and correspondinginsights for potentially solving them are also provided to inspire researchers. In addition, some state-of-the-art line segment detectionand description algorithms are evaluated without bias, and the evaluation code will be publicly available. The theoretical analysis, coupledwith the experimental results, can guide researchers in selecting the best method for their intended vision applications. Finally, this studyprovides insights for potentially interesting future research directions to attract more attention from researchers to this field.

CS2DIPs: Unsupervised HSI Super-Resolution Using Coupled Spatial and Spectral DIPs.

In recent years, fusing high spatial resolution multispectral images (HR-MSIs) and low spatial resolution hyperspectral images (LR-HSIs) has become a widely used approach for hyperspectral image super-resolution (HSI-SR). Various unsupervised HSI-SR methods based on deep image prior (DIP) have gained wide popularity thanks to no pre-training requirement. However, DIP-based methods often demonstrate mediocre performance in extracting latent information from the data. To resolve this performance deficiency, we propose a coupled spatial and spectral deep image priors (CS2DIPs) method for the fusion of an HR-MSI and an LR-HSI into an HR-HSI. Specifically, we integrate the nonnegative matrix-vector tensor factorization (NMVTF) into the DIP framework to jointly learn the abundance tensor and spectral feature matrix. The two coupled DIPs are designed to capture essential spatial and spectral features in parallel from the observed HR-MSI and LR-HSI, respectively, which are then used to guide the generation of the abundance tensor and spectral signature matrix for the fusion of the HSI-SR by mode-3 tensor product, meanwhile taking some inherent physical constraints into account. Free from any training data, the proposed CS2DIPs can effectively capture rich spatial and spectral information. As a result, it exhibits much superior performance and convergence speed over most existing DIP-based methods. Extensive experiments are provided to demonstrate its state-of-the-art overall performance including comparison with benchmark peer methods.

Comparison of predictive value for cage subsidence between MRI-based endplate bone quality and vertebral bone quality scores following transforaminal lumbar interbody fusion: a retrospective propensity-matched study.

BACKGROUND CONTEXT: Cage subsidence after lumbar fusion can lead to many adverse outcomes. Low bone mineral density (BMD) is a widely recognized risk factor for cage subsidence. Conventional methods can predict and evaluate BMD, but there are many shortcomings. Recently, MRI-based assessment of bone quality in specific parts of the vertebral body has been proposed, including scores for vertebral bone quality (VBQ) and endplate bone quality (EBQ). However, the predictive accuracy of the two scoring systems for cage subsidence after transforaminal lumbar interbody fusion (TLIF) remains unknown. Therefore, we investigated MRI-based VBQ and EBQ scores for assessing bone quality and compared their predictive value for cage subsidence after TLIF. PURPOSE: To compare the predictive value between MRI-based VBQ and EBQ scores for cage subsidence after TLIF. STUDY DESIGN/SETTING: A retrospective case-control study. PATIENTS SAMPLE: Patients with degenerative lumbar diseases underwent single-level TLIF at our medical center between 2014 and 2020, all of whom had preoperative MRIs available. OUTCOMES MEASURES: Cage subsidence, disc height, VBQ score, EBQ score, upper and lower vertebral body bone quality (UL-VBQ) score. METHODS: Data were retrospectively examined for a consecutive sample of 346 patients who underwent TLIF at our medical center between 2014 and 2020. Patients who subsequently experienced cage subsidence or not were matched to each other based on propensity scoring, and the two matched groups (52 patients each) were compared using conditional logistic regression to investigate the association between the potential radiographic factors and cage subsidence. Scores for VBQ and EBQ were assessed for their ability to predict cage subsidence in the matched patients based on the area under the receiver operative characteristic curve (AUC). RESULTS: Among matched patients, those who suffered cage subsidence had significantly higher VBQ score (3.7 vs 3.1, p<.001) and EBQ score (5.0 vs 4.3, p<.001), and regression linked greater risk of subsidence to higher VBQ score (OR 4.557, 95% CI 1.076-19.291, p=.039) and higher EBQ score (OR 5.396, 95% CI 1.158-25.146, p=.032). A cut-off VBQ score of 3.4 predicted the cage subsidence among matched patients with an AUC of 0.799, sensitivity of 84.6%, and specificity of 69.2%. A cut-off EBQ score of 4.7 predicted subsidence with an AUC of 0.829, sensitivity of 76.9%, and specificity of 82.7%. CONCLUSION: Higher VBQ and EBQ scores are associated with a greater risk of cage subsidence following TLIF, and EBQ may perform better because of greater specificity.

Preoperative geriatric nutritional risk index is useful factor for predicting postoperative delirium among elderly patients with degenerative lumbar diseases.

PURPOSE: It is the first study to evaluate the predictive value of the geriatric nutritional risk index (GNRI) on postoperative delirium (POD) after transforaminal lumber interbody fusion (TLIF) in elderly patients with degenerative lumbar diseases. METHODS: A retrospective study was conducted to assess the outcomes of TLIF surgery in elderly patients with lumbar degenerative disease between the years 2016 and 2022. Delirium was diagnosed by reviewing postoperative medical records during hospitalization, utilizing the Confusion Assessment Method. The geriatric nutritional risk index was calculated using the baseline serum albumin level and body weight. Multivariate logistic regression analysis was employed to identify the association between preoperative GNRI and postoperative delirium (POD). Additionally, a receiver operating characteristic curve was utilized to determine the optimal GNRI cutoff for predicting POD. RESULTS: POD was observed in 50 of the 324 patients. The GNRI was visibly reduced in the delirium group. The mean GNRI was 93.0 ± 9.1 in non-delirium group and 101.2 ± 8.2 in delirium group. On multivariate logistic regression, Risk of POD increases significantly with low GNRI and was an independent factor in predicting POD following TLIF (OR 0.714; 95% CI 0.540-0.944; p = 0.018). On receiver operating characteristic curve, the area under curve (AUC) for GNRI was 0.738 (95% CI 0.660-0.817). The cutoff value for GNRI according to the Youden index was 96.370 (sensitivity: 66.0%, specificity: 70.4%). CONCLUSION: Our study indicated that lower GNRI correlated significantly with POD after TLIF. Performing GNRI evaluation prior to TLIF may be an effective approach of predicting the risk for POD among elderly patients with degenerative lumbar diseases.

Tensor Completion for Alzheimer's Disease Prediction From Diffusion Tensor Imaging.

OBJECTIVE: Alzheimer's disease (AD) is a slowly progressive neurodegenerative disorder with insidious onset. Accurate prediction of the disease progression has received increasing attention. Cognitive scores that reflect patients' cognitive status have become important criteria for predicting AD. Most existing methods consider the relationship between neuroimages and cognitive scores to improve prediction results. However, the inherent structure information in interrelated cognitive scores is rarely considered. METHOD: In this article, we propose a relation-aware tensor completion multitask learning method (RATC-MTL), in which the cognitive scores are represented as a third-order tensor to preserve the global structure information in clinical scores. We combine both tensor completion and linear regression into a unified framework, which allows us to capture both inter and intra modes correlations in cognitive tensor with a low-rank constraint, as well as incorporate the relationship between biological features and cognitive status by imposing a regression model on multiple cognitive scores. RESULT: Compared to the single-task and state-of-the-art multi-task algorithms, our proposed method obtains the best results for predicting cognitive scores in terms of four commonly used metrics. Furthermore, the overall performance of our method in classifying AD progress is also the best. CONCLUSION: Our results demonstrate the effectiveness of the proposed framework in fully exploring the global structure information in cognitive scores. SIGNIFICANCE: This study introduces a novel concept of leveraging tensor completion to assist in disease diagnoses, potentially offering a solution to the issue of data scarcity encountered in prolonged monitoring scenarios.

Tractography-based automated identification of the retinogeniculate visual pathway with novel microstructure-informed supervised contrastive learning.

The retinogeniculate visual pathway (RGVP) is responsible for carrying visual information from the retina to the lateral geniculate nucleus. Identification and visualization of the RGVP are important in studying the anatomy of the visual system and can inform the treatment of related brain diseases. Diffusion MRI (dMRI) tractography is an advanced imaging method that uniquely enables in vivo mapping of the 3D trajectory of the RGVP. Currently, identification of the RGVP from tractography data relies on expert (manual) selection of tractography streamlines, which is time-consuming, has high clinical and expert labor costs, and is affected by inter-observer variability. In this paper, we present a novel deep learning framework, DeepRGVP , to enable fast and accurate identification of the RGVP from dMRI tractography data. We design a novel microstructure-informed supervised contrastive learning method that leverages both streamline label and tissue microstructure information to determine positive and negative pairs. We propose a simple and successful streamline-level data augmentation method to address highly imbalanced training data, where the number of RGVP streamlines is much lower than that of non-RGVP streamlines. We perform comparisons with several state-of-the-art deep learning methods that were designed for tractography parcellation, and we show superior RGVP identification results using DeepRGVP. In addition, we demonstrate a good generalizability of DeepRGVP to dMRI tractography data from neurosurgical patients with pituitary tumors and we show DeepRGVP can successfully identify RGVPs despite the effect of lesions affecting the RGVPs. Overall, our study shows the high potential of using deep learning to automatically identify the RGVP.

Multiple Complementary Priors for Multispectral Image Compressive Sensing Reconstruction.

Compressive sensing (CS) techniques using a few compressed measurements have drawn considerable interest in reconstructing multispectral imagery (MSI). Nonlocal-based tensor methods have been widely used for MSI-CS reconstruction, which employ the nonlocal self-similarity (NSS) property of MSI to obtain satisfactory results. However, such methods only consider the internal priors of MSI while ignoring important external image information, for example deep-driven priors learned from a corpus of natural image datasets. Meanwhile, they usually suffer from annoying ringing artifacts due to the aggregation of overlapping patches. In this article, we propose a novel approach for highly effective MSI-CS reconstruction using multiple complementary priors (MCPs). The proposed MCP jointly exploits nonlocal low-rank and deep image priors under a hybrid plug-and-play framework, which contains multiple pairs of complementary priors, namely, internal and external, shallow and deep, and NSS and local spatial priors. To make the optimization tractable, a well-known alternating direction method of multiplier (ADMM) algorithm based on the alternating minimization framework is developed to solve the proposed MCP-based MSI-CS reconstruction problem. Extensive experimental results demonstrate that the proposed MCP algorithm outperforms many state-of-the-art CS techniques in MSI reconstruction. The source code of the proposed MCP-based MSI-CS reconstruction algorithm is available at: https://github.com/zhazhiyuan/MCP_MSI_CS_Demo.git.

The Association between High Preoperative MRI-based Vertebral Bone Quality (VBQ) Score and Titanium Mesh Cage Subsidence after Anterior Cervical Corpectomy and Fusion.

OBJECTIVE: Recently, the MRI-based vertebral bone quality (VBQ) score has been shown to correlate with Hounsfeld units (HU) value, dual-energy X-ray absorptiometry (DEXA) T-score and predict osteoporotic fractures. Preoperative cervical HU value is an independent correlative factor for early titanium mesh cage (TMC) subsidence after anterior cervical corpectomy and fusion (ACCF). However, to date the direct association between cervical VBQ score and TMC subsidence has not been studied. This study aims to investigate the predictive effect of cervical VBQ score derived from sagittal non-contrast-enhanced T1-weighted MRI on the early TMC subsidence after ACCF. METHODS: Patients who underwent one-level ACCF from January 2016 to January 2020 were included. We retrospectively collected baseline data on age, sex, body mass index (BMI), disease type, level of surgery and radiology parameters. The cervical VBQ score was measured using preoperative non-contrast-enhanced T1-weighted MRI. Univariate and multivariate logistic regression analysis were performed to screen the independent risk factors of TMC subsidence. The receiver operating characteristic (ROC) curve and area under curve (AUC) were performed to assess the predictive ability of TMC subsidence based on the cervical VBQ score. Spearman correlation analysis was used to determine the correlations between the cervical VBQ score and TMC subsidence. RESULTS: A total of 134 patients who underwent one-level ACCF were included in this study, and 46 (34.33%) patients had TMC subsidence. Univariable analyses demonstrated that the age, TMC placement depth and VBQ score were associated with subsidence. The cervical VBQ score in the subsidence group was significantly higher than that in the no subsidence group (3.75 ± 0.45 vs. 3.20 ± 0.42, p < 0.001). The multivariate logistic regression analysis proved that the higher VBQ score (odds ratio[OR] = 13.563, 95% confidence interval [CI] 4.968 - 37.031, p < 0.001) was the only variable that significantly predicted subsidence. Using a VBQ score cutoff value of 3.445, the cervical VBQ score yielded a sensitivity of 69.6% and a specificity of 85.2% with an AUC of 0.810 to differentiate patients with subsidence and with no subsidence. CONCLUSION: Preoperative higher cervical VBQ score is an independent risk factor for TMC subsidence after ACCF. The cervical VBQ score may be a valuable tool for assisting in distinguishing the presence of TMC subsidence.

Simplified S1 vertebral bone quality (vbq) score to assess proximal junctional kyphosis after Lenke 5 adolescent idiopathic scoliosis surgery.

BACKGROUND: Proximal junctional kyphosis (PJK) is a common complication following corrective surgery for adolescent idiopathic scoliosis (AIS) with a Lenke 5 curve. Previous studies have suggested that PJK may be associated with osteopenia, which is prevalent in AIS patients. MRI-based vertebral bone quality (VBQ) scores have been proposed as a valuable tool to assess preoperative bone quality. However, accurately measuring VBQ scores in Lenke 5 AIS patients with a structural lumbar curve can be challenging. Recently, a simplified S1 VBQ score has been proposed as an alternative method when the traditional VBQ score is not applicable. This study aims to evaluate the predictive value of the simplified S1 VBQ score in predicting the occurrence of PJK after corrective surgery for Lenke 5 AIS. METHODS: We conducted a retrospective analysis of patient data to assess the predictive utility of the S1 VBQ score for PJK in Lenke 5 AIS patients. Demographic, radiographic, and surgical data were collected, and S1 VBQ scores were calculated based on preoperative T1-weighted MRI images. Univariate analysis, linear regression, and multivariate logistic regression were performed to identify potential risk factors for PJK and to assess the correlation between other variables and the S1 VBQ score. Receiver operating characteristic analysis and area under the curve values were used to evaluate the predictive efficiency of the S1 VBQ score for PJK. RESULTS: A total of 105 patients (aged 15.50 ± 2.36 years) were included in the analysis, of whom 24 (22.9%) developed PJK. S1 VBQ scores were significantly higher in the PJK group compared to the non-PJK group (2.83 ± 0.44 vs. 2.48 ± 0.30, P < 0.001), and there was a significant positive correlation between the S1 VBQ score and proximal junctional angle (PJA) (r = 0.46, P < 0.0001). Multivariate analysis revealed that the S1 VBQ scores and preoperative thoracic kyphosis (TK) were significant predictors of PJK. CONCLUSION: This study provided evidence that higher S1 VBQ scores were independently associated with PJK occurrence following corrective surgery for Lenke 5 AIS. Preoperative measurement of the S1 VBQ score on MRI may serve as a valuable tool in planning surgical correction for Lenke 5 AIS.

Restoring the ideal Roussouly sagittal alignment in Lenke 5 adolescent idiopathic scoliosis patients: a method for decreasing the risk of proximal junctional kyphosis.

PURPOSE: Although the Roussouly classification has been widely used in surgical planning for adult scoliosis patients, little is known about whether it can be used to guide sagittal correction for adolescent idiopathic scoliosis (AIS) patients. The purpose of this study was to explore whether the Roussouly classification could be used to help surgeons restore the ideal sagittal alignment for AIS patients to avoid the development of proximal junctional kyphosis (PJK). METHODS: In this retrospective cohort study, eighty-seven patients with Lenke 5 AIS who underwent surgery from January 2010 to August 2020 were enrolled and divided into two groups: the PJK group and the non-PJK group. All patients were classified into "current types" and "ideal types" according to two versions of the Roussouly classification, and the mismatch rate was evaluated in terms of the consistency between their current type and ideal type. Student's t test, Mann‒Whitney U test, Pearson's Chi-square test, and others were used to compare the two groups regarding patient demographic characteristics (age, sex, Risser sign, etc.) and radiographic parameters (sagittal vertical axis [SVA]; thoracic kyphosis [TK]; thoracolumbar junctional kyphosis [TLK]; lumbar lordosis [LL]; pelvic incidence [PI]; pelvic tilt [PT]; sacral slope [SS]; upper instrumented vertebra [UIV]; lower instrumented vertebra [LIV]; etc.). Multivariate logistic regression with backwards stepwise selection was performed to identify the risk factors for PJK. RESULTS: PJK was observed in 16 out of 87 patients (18.4%) until the final follow-up. The incidence of PJK was significantly higher in the patients not matching their ideal type than in those who did after surgery (60.9% vs. 3.1%, p = 0.000). The patients with ideal Type 1 had the highest incidence of PJK, while the lowest incidence was observed in patients with ideal Type 2 (50.0% vs. 5.1%, p = 0.000). The PJK group had greater TK, LL, and PI-LL than the non-PJK group before and after surgery. The postoperative PJA in the PJK group was also larger than that in the non-PJK group. Multivariate logistic regression revealed that postoperative Roussouly type mismatch was significantly associated with the occurrence of PJK (OR = 64.2, CI = 9.6-407.1, p = 0.000). CONCLUSIONS: The Roussouly classification could serve as a prognostic tool for PJK in Lenke 5 AIS patients. Corrective surgery should restore sagittal alignment with respect to the patient's ideal sagittal profile (according to the Roussouly classification based on the PI) to decrease the incidence of PJK in AIS patients.

Propelling Multi-Modal Therapeutics of PEEK Implants through the Power of NO evolving Covalent Organic Frameworks (COFs).

The design and fabrication of NO-evolving core-shell nanoparticles (denoted as NC@Fe), comprised of BNN6-laden COF@Fe3 O4 nanoparticles, are reported. This innovation extends to the modification of 3D printed polyetheretherketone scaffolds with NC@Fe, establishing a pioneering approach to multi-modal bone therapy tailored to address complications such as device-associated infections and osteomyelitis. This work stands out prominently from previous research, particularly those relying on the use of antibiotics, by introducing a bone implant capable of simultaneous NO gas therapy and photothermal therapy (PPT). Under NIR laser irradiation, the Fe3 O4 NP core (photothermal conversion agent) within NC@Fe absorbs photoenergy and initiates electron transfer to the loaded NO donor (BNN6), resulting in controlled NO release. The additional heat generated through photothermal conversion further propels the NC@Fe nanoparticles, amplifying the therapeutic reach. The combined effect of NO release and PPT enhances the efficacy in eradicating bacteria over a more extensive area around the implant, presenting a distinctive solution to conventional challenges. Thorough in vitro and in vivo investigations validate the robust potential of the scaffold in infection control, osteogenesis, and angiogenesis, emphasizing the timeliness of this unique solution in managing complicated bone related infectious diseases.

Compressed-SDR to HDR Video Reconstruction.

The new generation of organic light emitting diode display is designed to enable the high dynamic range (HDR), going beyond the standard dynamic range (SDR) supported by the traditional display devices. However, a large quantity of videos are still of SDR format. Further, most pre-existing videos are compressed at varying degrees for minimizing the storage and traffic flow demands. To enable movie-going experience on new generation devices, converting the compressed SDR videos to the HDR format (i.e., compressed-SDR to HDR conversion) is in great demands. The key challenge with this new problem is how to solve the intrinsic many-to-many mapping issue. However, without constraining the solution space or simply imitating the inverse camera imaging pipeline in stages, existing SDR-to-HDR methods can not formulate the HDR video generation process explicitly. Besides, they ignore the fact that videos are often compressed. To address these challenges, in this work we propose a novel imaging knowledge-inspired parallel networks (termed as KPNet) for compressed-SDR to HDR (CSDR-to-HDR) video reconstruction. KPNet has two key designs: Knowledge-Inspired Block (KIB) and Information Fusion Module (IFM). Concretely, mathematically formulated using some priors with compressed videos, our conversion from a CSDR-to-HDR video reconstruction is conceptually divided into four synergistic parts: reducing compression artifacts, recovering missing details, adjusting imaging parameters, and reducing image noise. We approximate this process by a compact KIB. To capture richer details, we learn HDR representations with a set of KIBs connected in parallel and fused with the IFM. Extensive evaluations show that our KPNet achieves superior performance over the state-of-the-art methods.

Postoperative Sclerotic Modic Changes after Transforaminal Lumbar Interbody Fusion: The Prevalence, Risk Factors, and Impact on Fusion.

STUDY DESIGN: A retrospective cohort study. OBJECTIVE: This study aimed to assess postoperative sclerotic Modic changes (MCs) following transforaminal lumbar interbody fusion (TLIF) for lumbar degenerative disc disease (LDD), investigating their prevalence, risk factors and association with clinical outcomes. SUMMARY OF BACKGROUND DATA: Sclerotic MCs may occur in patients with LDD after lumbar interbody fusion. The incidence and characteristics of postoperative sclerotic MCs, as well as their clinical impact, are unknown. METHODS: The study included 467 patients (510 levels) who underwent single or two-level TLIF surgery, divided into a postoperative sclerotic MC group (60 patients, 66 levels) and non-MC group (407 patients, 444 levels). The time of development and location of postoperative sclerotic MCs, fusion rate, cage subsidence, bilateral process decompression, and cross-link usage were recorded. Preoperative, postoperative, and follow-up VAS and ODI scores were collected. Multivaraible logistic regression was used to evaluate factors associated with the development of postoperative sclerotic MCs. RESULTS: The prevalence of postoperative sclerotic MCs was 12.8%. The postoperative sclerotic MC group had higher BMI. The postoperative sclerotic MC group demonstrated a fusion rate of 47%, significantly lower than that of the non-MC group (71%) at 6 months post-operation. At final follow-up, the fusion rate in the postoperative sclerotic MC group was 62%, significantly lower than that of the non-MC group (86%). Post-operative VAS and ODI scores were significantly higher in the group with postoperative sclerotic MCs. BMI and osteoporosis were significantly associated with the development of postoperative sclerotic MCs. CONCLUSION: Postoperative sclerotic MCs generally appear within the first year after surgery, with a prevalence of 12.8%. The presence of postoperative sclerotic MCs can adversely impact post-operative outcomes. To prevent postoperative sclerotic MCs, we postulate extending the immobilization period with external bracing and improving the management of BMI and osteoporosis in the peri-operative time window.

Hollow Cobalt Sulfide Nanospheres with Highly Enzyme-like Antibacterial Activities to Accelerate Infected Wound Healing.

The emergence of nanozymes presents a promising alternative to antibiotics for reactive oxygen species-mediated broad-spectrum antimicrobial purposes, but nanozymes still face challenges of low therapeutic efficiency and poor biocompatibility. Herein, we creatively prepared a novel kind of hollow cobalt sulfide (CoS) nanospheres with a unique mesoporous structure that is able to provide numerous active sites for enzyme-like reactions. The results revealed that 50 µg/mL of CoS nanospheres exhibited strong peroxidase- and oxidase-like activities under physiological conditions with the assistance of a low concentration of hydrogen peroxide (H2O2, 100 µM) while possessing highly efficient GSH-depletion ability, which endowed CoS nanospheres with triple enzyme-like properties to combat bacterial infections. The in vitro experiments demonstrated that the CoS nanozyme displayed significant antibacterial effects against both Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli). The in vivo implantation showed that the synthesized CoS effectively eliminated bacteria and promoted the recovery of infected wounds in rats while exhibiting a low cytotoxicity. This study provides a promising treatment strategy to accelerate infected wound healing.

Injectable mesoporous bioactive glass/sodium alginate hydrogel loaded with melatonin for intervertebral disc regeneration.

Intervertebral disc degeneration (IDD) is a major contributing factor to both lower back and neck pain. As IDD progresses, the intervertebral disc (IVD) loses its ability to maintain its disc height when subjected to axial loading. This failure in the weight-bearing capacity of the IVD is a characteristic feature of degeneration. Natural polymer-based hydrogel, derived from biological polymers, possesses biocompatibility and is able to mimic the structure of extracellular matrix, enabling them to support cellular behavior. However, their mechanical performance is relatively poor, thus limiting their application in IVD regeneration. In this study, we developed an injectable composite hydrogel, namely, Mel-MBG/SA, which is similar to natural weight-bearing IVD. Mesoporous bioactive glasses not only enhance hydrogels, but also act as carriers for melatonin (Mel) to suppress inflammation during IDD. The Mel-MBG/SA hydrogel further provides a mixed system with sustained Mel release to alleviate IL-1ß-induced oxidative stress and relieve inflammation associated with IDD pathology. Furthermore, our study shows that this delivery system can effectively suppress inflammation in the rat tail model, which is expected to further promote IVD regeneration. This approach presents a novel strategy for promoting tissue regeneration by effectively modulating the inflammatory environment while harnessing the mechanical properties of the material.

Preoperative Skull Traction, Anterior Debridement, Bone Grafting, and Internal Fixation for Cervical Tuberculosis with Severe Kyphosis.

OBJECTIVE: Cervical tuberculosis (CTB) readily causes local kyphosis, and its surgical strategy remains controversial. Although some previous studies suggested that the anterior approach could effectively treat CTB, patients in these studies only suffered mild to moderate kyphosis. Therefore, little is known about whether the anterior approach can achieve satisfactory outcomes in CTB patients with severe kyphosis. This study was performed to evaluate the safety and efficacy of preoperative skull traction combined with anterior surgery for the treatment of CTB patients with a severe kyphosis angle of more than 35°. METHODS: In this retrospective study, we enrolled 31 CTB patients with severe kyphosis who underwent preoperative skull traction combined with anterior surgery from April 2015 to January 2021. Patients were followed up for at least 2 years. Clinical data, such as operative time, blood loss, and postoperative hospital stay, were collected. The clinical outcomes included American Spinal Injury Association (ASIA) spinal cord injury grade, Japanese Orthopaedic Association (JOA) score, visual analog scale (VAS) score, and related complications. The radiological outcomes included the Cobb angle of cervical kyphosis at each time point and the bony fusion state. Clinical efficacy was evaluated by paired Student's t-test, Mann-Whitney U-test, and others. RESULTS: Six patients had involvement of one vertebra, 21 had involvement of two vertebrae, and four had involvement of three vertebrae. The most common level of vertebral involvement was C4-5, whereas the most common apical vertebra of kyphosis was C4. The mean kyphosis angle was 46.1° ± 7.7° preoperatively, and the flexibility on dynamic extension-flexion X-rays and cervical MRI was 17.5% ± 7.8% and 43.6% ± 11.0%, respectively (p = 0.000). The kyphosis angle significantly decreased to 13.2° ± 3.2° after skull traction, and it further corrected to -6.1° ± 4.3° after surgery, which was well maintained at the final follow-up with a mean Cobb angle of -5.4° ± 3.9°. The VAS and JOA scores showed significant improvement after surgery. The erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels normalized at 3 months after surgery. All patients achieved solid bone fusion, and no complications related to the instrumentation or recurrence were observed. CONCLUSION: Preoperative skull traction combined with anterior debridement, autologous iliac bone grafting, and internal plate fixation can be an effective and safe surgical method for the treatment of cervical tuberculosis with severe kyphosis. Skull traction can improve the safety and success rate of subsequent anterior corrective surgery.

Vertebral bone quality score as a novel predictor of proximal junctional kyphosis after thoracic adolescent idiopathic scoliosis surgery.

INTRODUCTION: Proximal junctional kyphosis (PJK) is one of the most common complications after thoracic AIS surgery. Previous studies reported that the etiology of PJK was associated with osteopenia and meanwhile the AIS patients were found osteopenia which could persist into adulthood. Recently, an MRI-based vertebral bone quality score (VBQ) was reported to be a promising tool which can assess preoperative bone quality. OBJECTIVE: This study aims to evaluate the utility of VBQ score in predicting PJK after corrective surgery for thoracic AIS (Lenke 1 and 2). METHODS: We conducted a retrospective study to identify the predictive efficiency of VBQ score for PJK in thoracic AIS patients. Demographic, radiographic parameters, and surgical variables were collected. VBQ score was calculated using preoperative T1-weighted MRI. Univariate analysis, linear regression, and multivariate logistic regression were performed to determine potential risk factors of PJK and correlation between other parameters and VBQ score. Receiver operating characteristic analysis and area under the curve values were utilized to evaluate the predictive efficiency of VBQ score for PJK. RESULTS: A total of 206 patients (aged 14.4 ± 2.3 years) were included, of which 33 (16.0%) developed PJK. VBQ scores were significantly different between the PJK and non-PJK groups (2.8 ± 0.2 vs 2.5 ± 0.2, P < 0.01). A significant positive correlation was found between VBQ score and PJA (R2 = 0.1728, P < 0.01).On multivariate analysis, VBQ score was the only significant predictor of PJK (odds ratio = 2.178, 95% CI = 1.644-2.885, P < 0.001), with a predictive accuracy of 83%. CONCLUSION: Higher VBQ scores were independently associated with PJK occurrence after corrective surgery for thoracic AIS. Preoperative measurement of VBQ score on MRI may serve as a valuable tool in planning thoracic AIS surgery.