Comparison of the Clinical Outcomes of Vesselplasty vs. Percutaneous Vertebroplasty for the Treatment of Neurologically Intact Osteoporotic Kümmell's Disease: A Retrospective Study.

Kummell's disease (KD) is a rare clinical complication of osteoporotic vertebral compression fractures (OVCFs). Minimally invasive surgery is an important way to treat KD. In this paper, we used Percutaneous Vertebroplasty (PVP) and Vesselplasty (VP) to treat KD. 125 patients with KD were admitted to our hospital. Among them, 89 patients received PVP and 36 received VP. All patients underwent operations successfully. VAS scores and ODI of both groups at each postoperative time point were lower than preoperatively. Postoperative Cobb angle of both groups postoperatively was lower than preoperatively (p < 0.05). The anterior height and ratio of vertebra compression of both groups postoperatively was lower than preoperatively (p < 0.05). Cement leakage occurred in 16 vertebrae (16/89) in PVP group and one (1/36) in VP group. Two patients suffered from transient paraplegia in PVP group immediately after operation. Adjacent vertebral fractures occurred in one patient in PVP group and one in VP group. Re-fracture of affected vertebra occurred in one patient in PVP group. Besides, four patients suffered from bone cement loosening in PVP group while one in VP group. Both PVP and VP play an important effect in pain relief and functional recovery for the treatment of KD. And VP is more effective than PVP in preventing cement leakage.

One-year mortality risk in older individuals with femoral intertrochanteric fracture: a tertiary center in China.

BACKGROUND: The accelerated growth of older individuals worldwide has increased the number of patients presenting with fragility hip fractures. Having a hip fracture can cause excess mortality, and patients with hip fracture have a higher risk of death than those without hip fracture. Most studies have treated hip fracture as a single, homogeneous condition, but hip fracture includes two major anatomic types: intertrochanteric fracture and femoral neck fracture. Few studies have specifically evaluated 1-year mortality risk in older individuals with femoral intertrochanteric fracture. The aim of this study was to evaluate 1-year mortality and factors associated with mortality in older individuals with femoral intertrochanteric fracture. METHODS: A retrospective review was conducted of 563 patients ≥ 65 years old who underwent surgery for femoral intertrochanteric fractures at our institution between January 2010 and August 2018. Patient demographics, comorbidities, and treatment were collected by retrospective chart review. Age, sex, Body Mass Index (BMI), American Society of Anesthesiologists (ASA) classification, Charlson comorbidity index (CCI), Arbeitsgemeinschaft Für Osteosynthesefragen (AO) fracture classification, haemoglobin value at admission, time to surgery, operation time, and intraoperative blood loss were risk factors to be tested. Multivariable logistic regression was used to evaluate associations between variables and death. RESULTS: Among the 563 patients, 49 died within 1 year after surgery, and the 1-year mortality rate was 8.7%. Multivariate analysis identified age > 80 years (OR = 4.038, P = 0.011), haemoglobin < 100 g/l (OR = 2.732, P = 0.002), ASA score ≥ 3 (OR = 2.551, P = 0.005), CCI ≥ 3 (OR = 18.412, P = 0.018) and time to surgery > 14 d (OR = 3.907, P = 0.030) as independent risk factors for 1-year mortality. Comorbidities such as myocardial infarction and chronic pulmonary disease were associated with 1-year mortality after adjusting for age > 80 years and time to surgery > 14 days. CONCLUSIONS: Patients over 80 years old with haemoglobin < 100 g/l, ASA score ≥ 3, CCI ≥ 3, and multiple comorbidities, especially myocardial infarction and chronic pulmonary disease before surgery, are at a higher risk of 1-year mortality. Doctors should pay more attention to these vulnerable patients, and a surgical delay greater than 14 days should be avoided.

Higher diagnostic value of next-generation sequencing versus culture in periprosthetic joint infection: A systematic review and meta-analysis.

BACKGROUND: The next-generation sequencing (NGS) has developed rapidly in the past decade and is becoming a promising diagnostic tool for periprosthetic infection (PJI). However, its diagnostic value for PJI is still uncertain. The purpose of this systematic review and meta-analysis was to evaluate the diagnostic value of NGS compared to culture. METHODS: In this systematic review and meta-analysis, electronic databases including PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science and clinicaltrials.gov were searched for studies from inception to 12 November 2023. Diagnostic parameters, such as sensitivity, specificity, diagnostic odds ratio and area under the summary receiver-operating characteristic (SROC) curve (AUC), were calculated for the included studies. A systematic review and meta-analysis was performed. RESULTS: A total of 22 studies with 2461 patients were included in our study. The pooled sensitivity, specificity and diagnostic odds ratio of NGS were 87% (95% confidence interval [CI]: 83-90), 94% (95% CI: 91-96) and 111 (95% CI: 70-177), respectively. On the other hand, the pooled sensitivity, specificity and diagnostic odds ratio of culture were 63% (95% CI: 58-67), 98% (95% CI: 96-99) and 93 (95% CI: 40-212), respectively. The SROC curve for NGS and culture showed that the AUCs are 0.96 (95% CI: 0.94-0.98) and 0.82 (95% CI: 0.79-0.86), respectively. CONCLUSION: This systematic review and meta-analysis found NGS had higher sensitivity and diagnostic accuracy but slightly lower specificity than culture. Based on the pooled results, we suggested NGS may have the potential to be a new tool for the diagnosis of PJI. LEVEL OF EVIDENCE: Level IV.

The Effectiveness of Virtual Reality, Augmented Reality, and Mixed Reality Rehabilitation in Total Knee Arthroplasty: A Systematic Review and Meta-Analysis.

BACKGROUND: Extended reality (XR), including virtual reality, augmented reality, and mixed reality, has been increasingly used in postoperative rehabilitation of total knee arthroplasty (TKA). The purpose of this systematic review and meta-analysis was to evaluate the effectiveness of XR-based rehabilitation in TKA compared to conventional rehabilitation. METHODS: In this study, we searched PubMed (MEDLINE), Embase (OVID), Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, and clinicaltrials.gov from inception to February 15, 2023 for eligible studies. A total of 14 randomized controlled trials with 989 patients were included in our study. The primary outcomes were pain and function. The secondary outcomes were anxiety and quality of life. A systematic review and meta-analysis was performed. RESULTS: The pooled data indicated XR-based rehabilitation significantly improved the visual analog scale (standardized mean difference [SMD] = -0.31, 95% Confidence Interval [CI] [-0.47 to -0.15], P = .0001), the Western Ontario and McMaster Universities Osteoarthritis Index (SMD = -0.46, 95% CI [-0.86 to -0.06], P = .02), range of motion (SMD = 0.40, 95% CI [0.09 to 0.72], P = .01), and anxiety scores (mean difference = -3.95, 95% CI [-7.76 to -0.13], P = .04) than conventional rehabilitation, but Timed Up and Go test and quality of life were similar in the 2 groups. CONCLUSION: This systematic review and meta-analysis found XR-based rehabilitation improved pain, function, and anxiety, but not quality of life in TKA compared to conventional rehabilitation within 1 month postoperatively. Based on the pooled results, we suggested that XR-based rehabilitation may have benefit in patients' postoperative rehabilitation in TKA.

The effectiveness of extended reality on relieving pain after total knee arthroplasty: a systematic review and meta-analysis of randomized controlled trials.

PURPOSE: Patients with total knee arthroplasty (TKA) often suffer from severe postoperative pain, which seriously hinders postoperative rehabilitation. Extended reality (XR), including virtual reality, augmented reality, and mixed reality, has been increasingly used to relieve pain after TKA. The purpose of this study was to evaluate the effectiveness of XR on relieving pain after TKA. METHODS: The electronic databases including PubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials (CENTRAL), and clinicaltrials.gov were searched for studies from inception to July 20, 2023. The outcomes were pain score, anxiety score, and physiological parameters related to pain. Meta-analysis was performed using the Review Manager 5.4 software. RESULTS: Overall, 11 randomized control trials (RCTs) with 887 patients were included. The pooled results showed XR had lower pain scores (SMD = - 0.31, 95% CI [- 0.46 to - 0.16], P < 0.0001) and anxiety scores (MD = - 3.95, 95% CI [- 7.76 to - 0.13], P = 0.04) than conventional methods. The subgroup analysis revealed XR had lower pain scores within 2 weeks postoperatively (SMD = - 0.49, 95% CI [- 0.76 to - 0.22], P = 0.0004) and XR had lower pain scores when applying XR combined with conventional methods (SMD = - 0.43, 95% CI [- 0.65 to - 0.20], P = 0.0002). CONCLUSION: This systematic review and meta-analysis found applying XR could significantly reduce postoperative pain and anxiety after TKA. When XR was combined with conventional methods, postoperative pain can be effectively relieved, especially within 2 weeks after the operation. XR is an effective non-pharmacological analgesia scheme.

Pathological hemodynamic changes and leukocyte transmigration disrupt the blood-spinal cord barrier after spinal cord injury.

BACKGROUND: Blood-spinal cord barrier (BSCB) disruption is a key event after spinal cord injury (SCI), which permits unfavorable blood-derived substances to enter the neural tissue and exacerbates secondary injury. However, limited mechanical impact is usually followed by a large-scale BSCB disruption in SCI. How the BSCB disruption is propagated along the spinal cord in the acute period of SCI remains unclear. Thus, strategies for appropriate clinical treatment are lacking. METHODS: A SCI contusion mouse model was established in wild-type and LysM-YFP transgenic mice. In vivo two-photon imaging and complementary studies, including immunostaining, capillary western blotting, and whole-tissue clearing, were performed to monitor BSCB disruption and verify relevant injury mechanisms. Clinically applied target temperature management (TTM) to reduce the core body temperature was tested for the efficacy of attenuating BSCB disruption. RESULTS: Barrier leakage was detected in the contusion epicenter within several minutes and then gradually spread to more distant regions. Membrane expression of the main tight junction proteins remained unaltered at four hours post-injury. Many junctional gaps emerged in paracellular tight junctions at the small vessels from multiple spinal cord segments at 15 min post-injury. A previously unnoticed pathological hemodynamic change was observed in the venous system, which likely facilitated gap formation and barrier leakage by exerting abnormal physical force on the BSCB. Leukocytes were quickly initiated to transverse through the BSCB within 30 min post-SCI, actively facilitating gap formation and barrier leakage. Inducing leukocyte transmigration generated gap formation and barrier leakage. Furthermore, pharmacological alleviation of pathological hemodynamic changes or leukocyte transmigration reduced gap formation and barrier leakage. TTM had very little protective effects on the BSCB in the early period of SCI other than partially alleviating leukocyte infiltration. CONCLUSIONS: Our data show that BSCB disruption in the early period of SCI is a secondary change, which is indicated by widespread gap formation in tight junctions. Pathological hemodynamic changes and leukocyte transmigration contribute to gap formation, which could advance our understanding of BSCB disruption and provide new clues for potential treatment strategies. Ultimately, TTM is inadequate to protect the BSCB in early SCI.

Salmonella enteritis spondylitis of thoracic spine: a case report and review of the literature.

BACKGROUND: Spondylitis is a very common back problem in orthopedics, but is rarely caused by Salmonella enteritidis. We herein reported an uncommon case of thoracic spondylitis caused by Salmonella enteritidis. CASE PRESENTATION: A 68-year-old man with high fever was diagnosed as salmonella septicemia initially. His condition was improved after antibacterial treatment. But the symptom of pyrexia was recurred after some days. He was then diagnosed with thoracic spondylitis caused by salmonella enteritidis. After that, he was put on strict antibiotic treatment, and underwent intervertebral lesion debridement, partial rib resection, intervertebral bone fusion and pedicle screw internal fixation. Subsequently, the patient had a significant relief in pain, temperature remained normal, and had no severe complications. CONCLUSIONS: Special attention should be paid to systemic pain and remain cautious to the occurrence of osteomyelitis in patients with Salmonella septicemia. Moreover, the treatment time for using sensitive antibiotics should be sufficient. Surgical treatment should be considered if strict conservative treatment is failed.

The causal effect of sarcopenia-associated traits on brain cortical structure: A Mendelian randomization study.

BACKGROUND: Previous observational studies have reported sarcopenia can affect the structure and function of brain cortical structure. However, the causality inferred from those studies was subjected to residual confounding and reverse causation. Herein, we use a two-sample Mendelian randomization (MR) analysis to illustrate the causal effect of sarcopenia-associated traits on brain cortical structure. METHODS: We selected appendicular lean mass (ALM), hand grip strength (left and right) (HGSL and HGSR), and usual walking pace (UWP) to symbolize sarcopenia. The definition of brain cortical structure is human brain cortical surface area (SA) and cortical thickness (TH) globally and in 34 functional regions measured by magnetic resonance imaging. Instrumental variables at the genome-wide significance level were obtained from publicly available datasets, and inverse variance weighted as the primary method was used for MR analysis. RESULT: At the global level, we found ALM (ß=2604.68, 95 % confidence interval (CI): 1886.17 to 3323.19, P = 1.20 × 10-12) and HGSR (ß=4733.05, 95 % CI: 2245.08 to 7221.01, P = 1.93 × 10-4) were associated with increased SA. At the region level, the SA of 25 functional gyrus without global weighted was influenced by ALM. The HGSR significantly increased SA of medial orbitofrontal and precentral gyrus without global weighted and ALM was associated with decrease of TH of lateral occipital gyrus with global weighted. No pleiotropy was detected. CONCLUSION: This was the first MR study investigated the causal effect of sarcopenia-associated traits on brain cortical structure. In our study, we revealed genetically predicted sarcopenia-associated traits including ALM and HGSR could affect brain cortical structure.

Recent advances in photo-crosslinkable methacrylated silk (Sil-MA)-based scaffolds for regenerative medicine: A review.

Silks fibroin can be chemically modified through amino acid side chains to obtain methacrylated silk (Sil-MA). Sil-MA could be processed into a variety of scaffold forms and combine synergistically with other biomaterials to form composites vehicle. The advent of Sil-MA material has enabled impressive progress in the development of various scaffolds based on Sil-MA type to imitate the structural and functional characteristics of natural tissues. This review highlights the reasonable design and bio-fabrication strategies of diverse Sil-MA-based tissue constructs for regenerative medicine. First, we elucidate modification methodology and characteristics of Sil-MA. Next, we describe characteristics of Sil-MA hydrogels, and focus on the design approaches and formation of different types of Sil-MA-based hydrogels. Thereafter, we present an overview of the recent advances in the application of Sil-MA based scaffolds for regenerative medicine, including detailed strategies for the engineering methods and materials used. Finally, we summarize the current research progress and future directions of Sil-MA in regenerative medicine. This review not only delineates the representative design strategies and their application in regenerative medicine, but also provides new direction in the fabrication of biomaterial constructs for the clinical translation in order to stimulate the future development of implants.

Multifunctional tannic acid-based nanocomposite methacrylated silk fibroin hydrogel with the ability to scavenge reactive oxygen species and reduce inflammation for bone regeneration.

The microenvironment of bone defect site is vital for bone regeneration. Severe bone defect is often accompanied with severe inflammation and elevated generation of reactive oxygen species (ROS) during bone repair. In recent years, the unfriendly local microenvironment has been paid more and more attention. Some bioactive materials with the ability to regulate the microenvironment to promote bone regeneration urgently need to be developed. Here, we develop a multifunctional composite hydrogel composed of photo-responsive methacrylate silk fibroin (SFMA), laponite (LAP) nanocomposite and tannic acid (TA), aiming to endow hydrogel with antioxidant, anti-inflammatory and osteogenic induction ability. Characterization results confirmed that the SFMA-LAP@TA hydrogel could significantly improve the mechanical properties of hydrogel. The ROS-Scavenging ability of the hydrogel enabled bone marrow mesenchymal stem cells (BMSCs) to survive against H2O2-induced oxidative stress. In addition, the SFMA-LAP@TA hydrogel effectively decreased the expression of pro-inflammatory factors in RAW264.7. More importantly, the SFMA-LAP@TA hydrogel could enhance the expression of osteogenic markers of BMSCs under inflammatory condition and greatly promote new bone formation in a critical-sized cranial defect model. Above all, the multifunctional hydrogel could effectively promote bone regeneration in vitro and in vivo by scavenging ROS and reducing inflammation, providing a prospective strategy for bone regeneration.

A nanoparticle reinforced microporous methacrylated silk fibroin hydrogel to promote bone regeneration.

Natural polymer-based hydrogels have been widely applied in bone tissue engineering due to their excellent biocompatibility and outstanding ability of drug encapsulation. However, they have relatively weak mechanical properties and lack bioactivity. Hence, we developed a bioactive nanoparticle composite hydrogel by incorporating LAPONITE®, which is an osteo-inductive inorganic nanoparticle. The incorporation of the nanoparticle significantly enhanced its mechanical properties. In vitro evaluation indicated that the nanocomposite hydrogel could exhibit good biocompatibility. Besides, the nanocomposite hydrogel was proved to have excellent osteogenic ability with up-regulated expression of osteogenic markers such as type I collagen (COL-I), runt-related transcription factor-2 (Runx-2) and osteocalcin (OCN). Furthermore, the in vivo study confirmed that the composite nanocomposite hydrogel could significantly promote new bone formation, providing a prospective strategy for bone tissue regeneration.

Double Vertebrae Kümmell Disease: Five Cases Report and Literature Review.

Kümmell disease (KD) is a complication of osteoporotic vertebral compression fractures. There is a lot of literature on KD, but the reported cases are all single vertebrae. This study reports five double vertebrae KD cases (10 levels) and discusses the possible underlying mechanisms with a literature review. One hundred and thirty vertebrae KD were diagnosed from 2074 osteoporotic vertebral compression fractures patients treated in our hospital between 2015 and 2019. These vertebrae KD were divided into two groups, one-level vertebrae KD (n = 125) and double-level KD (n = 5). The diagnosis of KD is mainly based on the signs of intravertebral vacuum cleft on X-ray or CT scan. Double vertebrae KD cases were classified by using the KD staging system. The analysis was performed on KD to compare age, gender, femoral neck bone mineral density of femoral neck (BMD), vertebrae distribution, Cobb angle, and visual analog scale (VAS) between one-level KD and double-level by t-tests, Welch's t-test, or hypothesis testing. The mean age of the participants in the one-level KD group was 78.69 years, while the mean age in the double-level KD group was 82.4 years. The difference was statistically significant (t = 3.66, p = 0.0004). There were 89 females and 36 males in the one-level KD group, while the double-level KD group had five females and no males. The femoral neck BMD was significantly different between the two groups, with the one-level KD group having a mean BMD of -2.75 and the double-level KD group having a mean BMD of -4.2 (t = 2.99, p= 0.0061). The vertebrae distribution was different between the groups, with the one-level KD group having vertebrae from T7 to L4 and the double-level KD group having vertebrae from T11 to L1. The Cobb angle was also significantly different between the groups, with the one-level KD group having a mean angle of 20.58 and the double-level KD group having a mean angle of 31.54 (t = 6.22, p = 0.0001). Finally, the VAS scores were similar between the two groups, with the one-level KD group having a mean score of 8.63 and the double-level KD group having a mean score of 8.8 (t = 1.35, p = 0.1790). It is concluded that double vertebrae Kümmell disease has special clinical significance due to its potential to cause greater spinal instability and deformity, increased risk of neurological symptoms, more complex surgical management, and greater risk of complications.

The effectiveness of virtual reality, augmented reality, and mixed reality training in total hip arthroplasty: a systematic review and meta-analysis.

BACKGROUND: Extended reality (XR), including virtual reality (VR), augmented reality (AR), and mixed reality (MR), has been used in the training of total hip arthroplasty (THA). This study aims to examine the effectiveness of XR training in THA. METHODS: In this systematic review and meta-analysis, we searched PubMed (MEDLINE), EMBASE (OVID), Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, and clinicaltrials.gov from inception to September 2022 for eligible studies. The Review Manager 5.4 software was applied to compare accuracy of inclination and anteversion, and surgical duration between XR training and conventional methods. RESULTS: We identified 213 articles, of which 4 randomized clinical trials and 1 prospective controlled study including 106 participants met inclusion criteria. The pooled data indicated the XR training had better accuracy of inclination and shorter surgical duration than conventional methods (MD = -2.07, 95% CI [- 4.02 to -0.11], P = 0.04; SMD = -1.30, 95% CI [- 2.01 to -0.60], P = 0.0003), but the accuracy of anteversion was similar in the two groups. CONCLUSIONS: This systematic review and meta-analysis found XR training had better accuracy of inclination and shorter surgical duration than conventional methods in THA, but the accuracy of anteversion was similar. Based on the pooled results, we suggested that XR training can better improve trainees' surgical skills than conventional methods in THA.

Early surgery within 48 h was associated with reduced perioperative blood loss and red blood cell transfusion requirements in older patients with hip fracture: a retrospective study.

PURPOSE: The aim of this study was to analyze the relationship between the timing of surgery and perioperative blood loss, red blood cell (RBC) transfusion rate, and RBC transfusion volume in older patients with hip fracture. METHODS: From January 2020 to August 2022, this retrospective study enrolled older patients with hip fracture who underwent surgery in our hospital. The demographics, fracture type, type of surgery, time from injury to hospital, timing of surgery, medical history (hypertension, diabetes), duration of surgery, intraoperative blood loss, laboratory tests, and preoperative, postoperative and perioperative RBC transfusion requirements were recorded and analyzed. According to the surgical treatment within 48 h or after 48 h after admission, the patients were divided into early surgery group (ES) and delayed surgery group (DS). RESULTS: A total of 243 older patients with hip fracture were finally included in the study. Among these, 96 patients (39.51%) underwent surgery within 48 h of admission and 147 (60.49%) underwent surgery after this time. Total blood loss (TBL) in the ES group was lower than that in the DS group (576.03 ± 265.57 ml vs 699.26 ± 380.58 ml, P = 0.003). Preoperative RBC transfusion rate, and preoperative and perioperative RBC transfusion volume in the ES group were significantly lower than those in the DS group (15.63% vs 26.53%, P = 0.046; 50.00 ± 128.15 ml vs 117.01 ± 225.85 ml, P = 0.004; 80.21 ± 196.63 ml vs 144.90 ± 253.52 ml, P = 0.027). CONCLUSION: Timing of surgery within 48 h of admission for older patients with hip fracture was associated with reduced the total blood loss and RBC transfusion requirements during the perioperative period.

Augmented reality-assisted versus conventional total hip arthroplasty: a systematic review and meta-analysis.

BACKGROUND: Extended reality (XR), including virtual reality, augmented reality (AR), and mixed reality, has been used to help achieve accurate acetabular cup placement in total hip arthroplasty (THA). This study aimed to compare the differences between XR-assisted and conventional THA. METHODS: In this systematic review and meta-analysis, electronic databases including PubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials (CENTRAL), and clinicaltrials.gov were searched for studies from inception to September 10, 2023. The outcomes were accuracy of inclination and anteversion, duration of surgery, and intraoperative blood loss. Meta-analysis was performed using Review Manager 5.4 software. RESULTS: A total of five studies with 396 patients were included in our study. The pooled results indicated AR-assisted THA had better accuracy of inclination and anteversion than conventional THA (SMD = - 0.51, 95% CI [- 0.96 to - 0.07], P = 0.02; SMD = - 0.96, 95% CI [- 1.19 to - 0.72], P < 0.00001), but duration of surgery and intraoperative blood loss were similar in the two groups. CONCLUSION: This systematic review and meta-analysis found that AR-assisted THA had better accuracy of inclination and anteversion than conventional THA, but the duration of surgery and intraoperative blood loss were similar in the two groups. Based on the pooled results, we suggested that AR can provide more precise acetabular cup placement than conventional methods in THA.

The neurovascular unit in healthy and injured spinal cord.

The neurovascular unit (NVU) reflects the close temporal and spatial link between neurons and blood vessels. However, the understanding of the NVU in the spinal cord is far from clear and largely based on generalized knowledge obtained from the brain. Herein, we review the present knowledge of the NVU and highlight candidate approaches to investigate the NVU, particularly focusing on the spinal cord. Several unique features maintain the highly regulated microenvironment in the NVU. Autoregulation and neurovascular coupling ensure regional blood flow meets the metabolic demand according to the blood supply or local neural activation. The blood-central nervous system barrier partitions the circulating blood from neural parenchyma and facilitates the selective exchange of substances. Furthermore, we discuss spinal cord injury (SCI) as a common injury from the perspective of NVU dysfunction. Hopefully, this review will help expand the understanding of the NVU in the spinal cord and inspire new insights into SCI.

Green synthesis of metal-organic framework loaded dexamethasone on wood aerogels for enhanced cranial bone regeneration.

Bone defects have attracted increasing attention in clinical settings. To date, there have been no effective methods to repair defective bones. Balsa wood aerogels are considered as an excellent source of chemicals for chemical modification to facilitate the in situ immobilization of zeolitic imidazolate framework-8. Furthermore, dexamethasone has received considerable attention for bone tissue engineering. In this study, for the first time, a simple but effective one-pot method for developing a novel zeolitic imidazolate framework-8 with different concentrations of dexamethasone was developed. These findings illustrate that the novel scaffold has a significant positive impact on osteogenic differentiation in vitro and repairs defects in vivo, suggesting that it can be used in bone tissue engineering.

Dual-crosslinked network of polyacrylamide-carboxymethylcellulose hydrogel promotes osteogenic differentiation in vitro.

In our previous study, we successfully designed a dual-crosslinked network hydrogel by introducing the monomers acrylamide (AM), carboxymethylcellulose (CMC), zeolitic imidazolate framework-8 (ZIF-8), and alendronate (Aln). With the simultaneous presentation of physical and chemical crosslinks, the fabricated hydrogel with 10 % concentration of Aln@ZIF-8 (PAM-CMC-10%Aln@ZIF-8) exhibited excellent mechanical characteristics, high Aln loading efficiency (63.83 %), and a slow release period (6 d). These results demonstrate that PAM-CMC-10%Aln@ZIF-8 is a potential carrier for delaying Aln. In this study, we mainly focused on the biocompatibility and osteogenic ability of PAM-CMC-10%Aln@ZIF-8 in vitro, which is a continuation of our previous work. First, this study investigated the biocompatibility of dual-crosslinked hydrogels using calcein-AM/Propidium Iodide and cell counting kit-8. The morphology of rat bone mesenchymal stem cells was assessed using FITC-phalloidin/DAPI and vinculin immunostaining. Finally, osteogenic induction ability in vitro was assessed via alkaline phosphatase expression and alizarin red S staining, which was also confirmed using real-time PCR at the gene level and immunofluorescence at the protein level. The results indicated that the introduction of Aln enabled a dual-crosslinked hydrogel with superior biocompatibility and outstanding osteogenic differentiation ability in vitro, providing a solid foundation for subsequent animal experiments in vivo.

Moderate systemic therapeutic hypothermia is insufficient to protect blood-spinal cord barrier in spinal cord injury.

Blood-spinal cord barrier (BSCB) disruption is a pivotal event in spinal cord injury (SCI) that aggravates secondary injury but has no specific treatment. Previous reports have shown that systemic therapeutic hypothermia (TH) can protect the blood-brain barrier after brain injury. To verify whether a similar effect exists on the BSCB after SCI, moderate systemic TH at 32°C was induced for 4 h on the mice with contusion-SCI. In vivo two-photon microscopy was utilized to dynamically monitor the BSCB leakage 1 h after SCI, combined with immunohistochemistry to detect BSCB leakage at 1 and 4 h after SCI. The BSCB leakage was not different between the normothermia (NT) and TH groups at both the in vivo and postmortem levels. The expression of endothelial tight junctions was not significantly different between the NT and TH groups 4 h after SCI, as detected by capillary western blotting. The structural damage of the BSCB was examined with immunofluorescence, but the occurrence of junctional gaps was not changed by TH 4 h after SCI. Our results have shown that moderate systemic TH induced for 4 h does not have a protective effect on the disrupted BSCB in early SCI. This treatment method has a low value and is not recommended for BSCB disruption therapy in early SCI.

The Glial Cells Respond to Spinal Cord Injury.

It is been over 100 years since glial cells were discovered by Virchow. Since then, a great deal of research was carried out to specify these further roles and properties of glial cells in central nervous system (CNS). As it is well-known that glial cells, such as astrocytes, microglia, oligodendrocytes (OLs), and oligodendrocyte progenitor cells (OPCs) play an important role in supporting and enabling the effective nervous system function in CNS. After spinal cord injury (SCI), these glial cells play different roles in SCI and repair. In this review, we will discuss in detail about the role of glial cells in the healthy CNS and how they respond to SCI.