Spatial Distribution of Brønsted Acid Sites Determines the Mobility of Reactive Cu Ions in the Cu-SSZ-13 Catalyst during the Selective Catalytic Reduction of NOx with NH3.

The formation of dimer-Cu species, which serve as the active sites of the low-temperature selective catalytic reduction of NOx with NH3 (NH3-SCR), relies on the mobility of CuI species in the channels of the Cu-SSZ-13 catalysts. Herein, the key role of framework Brønsted acid sites in the mobility of reactive Cu ions was elucidated via a combination of density functional theory calculations, in situ impedance spectroscopy, and in situ diffuse reflectance ultraviolet-visible spectroscopy. When the number of framework Al sites decreases, the Brønsted acid sites decrease, leading to a systematic increase in the diffusion barrier for [Cu(NH3)2]+ and less formation of highly reactive dimer-Cu species, which inhibits the low-temperature NH3-SCR reactivity and vice versa. When the spatial distribution of Al sites is uneven, the [Cu(NH3)2]+ complexes tend to migrate from an Al-poor cage to an Al-rich cage (e.g., cage with paired Al sites), which effectively accelerates the formation of dimer-Cu species and hence promotes the SCR reaction. These findings unveil the mechanism by which framework Brønsted acid sites influence the intercage diffusion and reactivity of [Cu(NH3)2]+ complexes in Cu-SSZ-13 catalysts and provide new insights for the development of zeolite-based catalysts with excellent SCR activity by regulating the microscopic spatial distribution of framework Brønsted acid sites.

From hyperglycemia to intervertebral disc damage: exploring diabetic-induced disc degeneration.

The incidence of lumbar disc herniation has gradually increased in recent years, and most patients have symptoms of low back pain and nerve compression, which brings a heavy burden to patients and society alike. Although the causes of disc herniation are complex, intervertebral disc degeneration (IDD) is considered to be the most common factor. The intervertebral disc (IVD) is composed of the upper and lower cartilage endplates, nucleus pulposus, and annulus fibrosus. Aging, abnormal mechanical stress load, and metabolic disorders can exacerbate the progression of IDD. Among them, high glucose and high-fat diets (HFD) can lead to fat accumulation, abnormal glucose metabolism, and inflammation, which are considered important factors affecting the homeostasis of IDD. Diabetes and advanced glycation end products (AGEs) accumulation- can lead to various adverse effects on the IVD, including cell senescence, apoptosis, pyroptosis, proliferation, and Extracellular matrix (ECM) degradation. While current research provides a fundamental basis for the treatment of high glucose-induced IDD patients. further exploration into the mechanisms of abnormal glucose metabolism affecting IDD and in the development of targeted drugs will provide the foundation for the effective treatment of these patients. We aimed to systematically review studies regarding the effects of hyperglycemia on the progress of IDD.

Comparison of the S8 navigation system and the TINAVI orthopaedic robot in the treatment of upper cervical instability.

The objective is to compare the clinical efficacy and safety of the S8 navigation system and the Tinavi orthopaedic surgery robot in the treatment of upper cervical instability. The research methods adopted are as follows. The clinical data of patients with upper cervical instability who underwent surgery from May 2021 to December 2021 were analysed retrospectively. Patients were divided into a navigation group (assisted by the S8 navigation system) and a tinavi group (assisted by the Tinavi robot) according to the auxiliary system used. Computed tomography and digital radiography were performed after the operation. The accuracy of pedicle screw placement was evaluated using the criteria put forward by Rampersaud. Degree of facet joint violation, visual analogue scale score, neck disability index and Japanese orthopaedic association score were recorded and assessed during follow-up examinations in both groups. Record two groups of surgery-related indicators. Record the complications of the two groups. A total of 50 patients were included. 21 patients in the navigation group and 29 in the tinavi group. The results of the study are as follows. The average follow-up time was 12.1 months. There was no significant difference in nail placement accuracy between the navigation and tinavi groups (P > 0.05); however, the navigation group had a significantly higher rate of facet joint violation than that of tinavi group (P < 0.05), and the screws were placed closer to the anterior cortex (P < 0.05). Significantly more intraoperative fluoroscopies were performed in the tinavi group than in the navigation group, and the operation time was significantly longer in the tinavi group than in the navigation group (P < 0.05). The time of single nail implantation, intraoperative blood loss and incision length in navigation group were significantly longer than those in tinavi group. There were no statistically significant differences in other indicators between the two groups (P > 0.05). We come to the following conclusion. The Stealth Station S8 navigation system (Medtronic, USA), which also uses an optical tracking system, and the Tinavi Orthopedic robot have shown the same high accuracy and satisfactory clinical results in the treatment of upper cervical instability. Although the S8 navigation system still has many limitations, it still has good application prospects and is a new tool for spine surgery.

Unexpected Promotion Effect of H2O on the Selective Catalytic Reduction of NOx with NH3 over Cu-SSZ-39 Catalysts.

Water molecules commonly inhibit the selective catalytic reduction (SCR) of NOx with NH3 on most catalysts, and water resistance is a long-standing challenge for SCR technology. Herein, by combining experimental measurements and density functional theory (DFT) calculations, we found that water molecules do not inhibit and even promote the NOx conversion to some extent over the Cu-SSZ-39 zeolites, a promising SCR catalyst. Water acting as a ligand on active Cu sites and as a reactant in the SCR reaction significantly improves the O2 activation performance and reduces the overall energy barrier of the catalytic cycle. This work unveils the mechanism of the unexpected promotion effect of water on the NH3-SCR reaction over Cu-SSZ-39 and provides fundamental insight into the development of zeolite-based SCR catalysts with excellent activity and water resistance.

Sono-activated materials for enhancing focused ultrasound ablation: Design and application in biomedicine.

The ablation effect of focused ultrasound (FUS) has played an increasingly important role in the biomedical field over the past decades, and its non-invasive features have great advantages, especially for clinical diseases where surgical treatment is not available or appropriate. Recently, rapid advances in the adjustable morphology, enzyme-mimetic activity, and biostability of sono-activated materials have significantly promoted the medical application of FUS ablation. However, a systematic review of sono-activated materials based on FUS ablation is not yet available. This progress review focuses on the recent design, fundamental principles, and applications of sono-activated materials in the FUS ablation biomedical field. First, the different ablation mechanisms and the key factors affecting ablation are carefully determined. Then, the design of sono-activated materials with high FUS ablation efficiencies is comprehensively discussed. Subsequently, the representative biological applications are summarized in detail. Finally, the primary challenges and future perspectives are also outlined. We believe this timely review will provide key information and insights for further exploration of focused ultrasound ablation and new inspiration for designing future sono-activated materials. STATEMENT OF SIGNIFICANCE: The ablation effect of focused ultrasound (FUS) has played an increasingly important role in the biomedical field over the past decades. However, there are also some challenges of FUS ablation, such as skin burns, tumour recurrence after thermal ablation, and difficulty in controlling cavitation ablation. The rapid advance in adjustable morphology, enzyme-mimetic activity, and biostability of sono-activated materials has significantly promoted the medical application of FUS ablation. However, the systematic review of sono-activated materials based on FUS ablation is not yet available. This progress review focuses on the recent design, fundamental principles, and applications in the FUS ablation biomedical field of sono-activated materials. We believe this timely review will provide key information and insights for further exploration of FUS ablation.

Retrospective analysis of 10 cases with esophageal fistula after anterior surgery for cervical spine fracture.

Objective: This study aims to discuss the appropriate treatment of esophageal fistula following anterior surgery for cervical spine fracture. Methods: Clinical data of patients with cervical spine fracture treated at our research center from January 2000 to December 2019 were screened. Data of patients with esophageal fistula were included, and the causes of injury, diagnosis, and treatment were retrospectively analyzed. Results: A total of 3578 patients with cervical spine fracture were screened, among whom there were 10 cases (0.28 %) of esophageal fistula. 60 % of the cases were early-onset and all were caused by intraoperative electric knife injury. The positive rate of early endoscopy was only 25 %, while routine radiography showed a positive rate of 33.3 % after three attempts. Among the six patients with early-onset esophageal fistula, three underwent sternocleidomastoid flap transfer and two underwent primary suture, all achieving successful healing. In the four cases of late-onset esophageal fistula, two patients received implant removal, debridement, incision lavage, and sternocleidomastoid muscle flap transfer three weeks later. One patient received implant removal, debridement, vacuum sealing drainage, followed by sternocleidomastoid muscle pedicle transfer muscle flap plus lavage two weeks later and achieved complete recovery. All patients gargled alternately with metronidazole and chlorhexidine gargle after surgery. Conclusion: The occurrence of esophageal fistula is associated with surgical procedures, esophageal injury, and implant compression. Esophagography and endoscopy are the primary diagnostic methods, while incision exploration after ingestion of food mixed with methylene serves as a supplementary approach. Recommended treatments include alternating metronidazole and chlorhexidine gargles, esophageal rest, repair of the fistula, muscle flap packing, lavage and drainage, nutritional support, and removal of internal fixation if necessary. Post-surgery administration of antibiotics should continue until three consecutive lavage cultures yield negative results.

MDIG-mediated H3K9me3 demethylation upregulates Myc by activating OTX2 and facilitates liver regeneration.

The mineral dust-induced gene (MDIG) comprises a conserved JmjC domain and has the ability to demethylate histone H3 lysine 9 trimethylation (H3K9me3). Previous studies have indicated the significance of MDIG in promoting cell proliferation by modulating cell-cycle transition. However, its involvement in liver regeneration has not been extensively investigated. In this study, we generated mice with liver-specific knockout of MDIG and applied partial hepatectomy or carbon tetrachloride mouse models to investigate the biological contribution of MDIG in liver regeneration. The MDIG levels showed initial upregulation followed by downregulation as the recovery progressed. Genetic MDIG deficiency resulted in dramatically impaired liver regeneration and delayed cell cycle progression. However, the MDIG-deleted liver was eventually restored over a long latency. RNA-seq analysis revealed Myc as a crucial effector downstream of MDIG. However, ATAC-seq identified the reduced chromatin accessibility of OTX2 locus in MDIG-ablated regenerating liver, with unaltered chromatin accessibility of Myc locus. Mechanistically, MDIG altered chromatin accessibility to allow transcription by demethylating H3K9me3 at the OTX2 promoter region. As a consequence, the transcription factor OTX2 binding at the Myc promoter region was decreased in MDIG-deficient hepatocytes, which in turn repressed Myc expression. Reciprocally, Myc enhanced MDIG expression by regulating MDIG promoter activity, forming a positive feedback loop to sustain hepatocyte proliferation. Altogether, our results prove the essential role of MDIG in facilitating liver regeneration via regulating histone methylation to alter chromatin accessibility and provide valuable insights into the epi-transcriptomic regulation during liver regeneration.

Comparison of the efficacies of TINAVI robot-assisted surgery and conventional open surgery for Levine-Edward type IIA (postreduction) hangman fractures.

The objective was to compare the clinical efficacy of percutaneous pedicle screw internal fixation with the aid of the TINAVI orthopaedic surgery robot with that of traditional open surgery for Levine-Edward type IIA (postreduction) hangman fractures and to evaluate the safety and efficacy of the TINAVI robot-assisted orthopaedic surgery procedure. The clinical data of 60 patients with Levine-Edward type IIA (postreduction) hangman fractures treated surgically from June 2015 to February 2022 were analysed retrospectively. Among these patients, 25 were treated with percutaneous pedicle screw fixation under TINAVI (the robot group), and 35 were treated with pedicle screw implantation assisted by a conventional C-arm X-ray machine (the traditional operation group). The pedicle screw placement grade was evaluated according to the Rampersaud scale. The correct rate of pedicle screw placement was calculated. The invasion of adjacent facet joints, VAS score (Visual Analogue Scale), NDI score (Neck Disability Index), SF-36 score (36-Item Short-Form Health Survey questionnaire), EQ-5D score (EuroQol-5 dimensions questionnaire) and operation-related data were recorded, and patients were followed up. All patients were followed up for an average of 15.0 ± 3.4 months. The accuracy of screw placement in the robot group was higher than that in the traditional operation group, while the rates of intraoperative blood loss and invasion of the facet joint were lower and the incision length and length of hospital stay were shorter. On the 3rd day after the operation, the VAS score in the robot group was significantly higher than that in the traditional operation group, but there was no significant difference in the NDI score. On the 3rd day after the operation, the SF-36 and EQ-5 questionnaire scores of the robot group were better than those of the traditional operation group. No complications occurred in any of the patients. Postoperative cervical X-ray showed that the cervical vertebra was stable, and there was no fracture, angle or displacement. Postoperative CT showed that all fractures healed, and the average healing time was 3.4 months. The treatment of Levine-Edward IIA (postrepositioning) hangman fractures with percutaneous pedicle fixation assisted by the TINAVI orthopaedic surgery robot can significantly improve screw placement accuracy with a low rate of invasion of the adjacent facet joint, a short operation time, a low bleeding rate, and high patient satisfaction. Although there are still many disadvantages, it still has good prospects for application.

Epigenome-wide development and validation of a prognostic methylation score in intrahepatic cholangiocarcinoma based on machine learning strategies.

Background: Clinical parameter-based nomograms and staging systems provide limited information for the prediction of survival in intrahepatic cholangiocarcinoma (ICC) patients. In this study, we developed a methylation signature that precisely predicts overall survival (OS) after surgery. Methods: An epigenome-wide study of DNA methylation based on whole-genome bisulfite sequencing (WGBS) was conducted for two independent cohorts (discovery cohort, n=164; validation cohort, n=170) from three hepatobiliary centers in China. By referring to differentially methylated regions (DMRs), we proposed the concept of prognostically methylated regions (PMRs), which were composed of consecutive prognostically methylated CpGs (PMCs). Using machine learning strategies (Random Forest and the least absolute shrinkage and selector regression), a prognostic methylation score (PMS) was constructed based on 14 PMRs in the discovery cohort and confirmed in the validation cohort. Results: The C-indices of the PMS for predicting OS in the discovery and validation cohorts were 0.79 and 0.74, respectively. In the whole cohort, the PMS was an independent predictor of OS [hazard ratio (HR) =8.12; 95% confidence interval (CI): 5.48-12.04; P<0.001], and the C-index (0.78) of the PMS was significantly higher than that of the Johns Hopkins University School of Medicine (JHUSM) nomogram (0.69, P<0.001), the Eastern Hepatobiliary Surgery Hospital (EHBSH) nomogram (0.67, P<0.001), American Joint Committee on Cancer (AJCC) tumor-node-metastasis (TNM) staging system (0.61, P<0.001), and MEGNA prognostic score (0.60, P<0.001). The patients in quartile 4 of PMS could benefit from adjuvant therapy (AT) (HR =0.54; 95% CI: 0.32-0.91; log-rank P=0.043), whereas those in the quartiles 1-3 could not. However, other nomograms and staging system failed to do so. Further analyses of potential mechanisms showed that the PMS was associated with tumor biological behaviors, pathway activation, and immune microenvironment. Conclusions: The PMS could improve the prognostic accuracy and identify patients who would benefit from AT for ICC patients, and might facilitate decisions in treatment of ICC patients.

Comparison of surgical efficacy between O-arm combined with CT 3D real-time navigation system and Tinavi robot-assisted treatment of adolescent congenital scoliosis.

OBJECTIVE: To compare the orthopedic function and clinical efficacy between the orthopedic surgery guided by the Stealth Station 8 Navigation System and the Tinavi robot-assisted orthopedic surgery for the treatment of congenital scoliosis. METHODS: A retrospective analysis was performed on the patients who underwent surgical treatment for congenital scoliosis between May 2021 and October 2021. Patients were divided into the navigation group or the robotic group according to the adjunct system used. Postoperative computed tomography (CT) and digital radiography (DR) scans were conducted to assess the orthopedic outcomes. Specifically, the pedicle screw placement accuracy was measured, and the accuracy rate was calculated based on the parameters of the Scoliosis Research Society (SRS), sagittal vertical axis (SVA), distance between the C7 plumb line and the central sacral vertical line (C7PL-CSVL), lumbar lordosis (LL), and spine correction rate. Clinical data of both groups were recorded. RESULTS: A total of 60 patients, including 20 cases in the navigation group and 40 cases in the Tinavi group, were selected for this study. All patients were followed up for a mean of 12.1 months. We found that the spine correction rate, C7PL-CSVL, and SVA were better in the navigation group than in the robot group, while there was no significant difference in the pedicle screw placement accuracy between these two groups (P=0.806). However, the rate of small joint protrusion was significantly higher in the navigation group (P=0.000), and the screws were also closer to the anterior cortex in the navigation group (P=0.020). In contrast, the number of scans and intraoperative fluoroscopic dose were higher in the robot group than in the navigation group. The rest of the data were not significantly different between these two groups. CONCLUSION: O-arm combined with CT 3D real-time navigation system not only has a better orthopedic effect than Tinavi orthopedic robot which also uses optical tracking system in the treatment of adolescent congenital scoliosis, but also exhibits a satisfactory clinical effect. Therefore, although it has several drawbacks, the navigation system is still a good clinical treatment option for scoliosis.

CircZNF215 promotes tumor growth and metastasis through inactivation of the PTEN/AKT pathway in intrahepatic cholangiocarcinoma.

BACKGROUND: Increasing evidence shows that circular RNAs (circRNAs), a novel class of noncoding RNAs, play a crucial role in the development of cancers, including intrahepatic cholangiocarcinoma (iCCA). Nevertheless, their functions and exact mechanisms in iCCA progression and metastasis are still unclear. Ipatasertib is a highly selective inhibitor of AKT that inhibits tumor growth by blocking the PI3K/AKT pathway. In addition, phosphatase and tensin homolog (PTEN) can also inhibit the activation of the PI3K/AKT pathway, but it is not clear whether the cZNF215-PRDX-PTEN axis plays a role in the antitumor activity of ipatasertib. METHODS: We identified a new circRNA (circZNF215, termed cZNF215) through high-throughput circRNA sequencing (circRNA-seq). In addition, RT‒qPCR, immunoblot assay, RNA pull-down assay, RNA immunoprecipitation (RIP) assay, and fluorescence in situ hybridization assay (FISH) were used to investigate the interaction of cZNF215 with peroxiredoxin 1 (PRDX1). Coimmunoprecipitation (Co-IP) assays and duolink in situ proximity ligation assays (PLAs) were conducted to analyze the effects of cZNF215 on the interaction between PRDX1 and PTEN. Finally, we tested the potential effects of cZNF215 on the antitumor activity of ipatasertib with in vivo experiments. RESULTS: We found that cZNF215 expression was obviously upregulated in iCCA tissues with postoperative metastases and was correlated with iCCA metastasis and poor outcome in patients with iCCA. We further revealed that overexpression of cZNF215 promoted iCCA cell growth and metastasis in vitro and in vivo, while cZNF215 knockdown had the opposite effect. Mechanistic studies suggested that cZNF215 competitively interacted with PRDX1, which blocked the association between PRDX1 and PTEN, subsequently leading to oxidation-induced inactivation of the PTEN/AKT pathway and finally contributing to iCCA progression and metastasis. Additionally, we also revealed that silencing cZNF215 in iCCA cells had the potential to enhance the antitumor effect of ipatasertib. CONCLUSIONS: Our study demonstrates that cZNF215 facilitates iCCA progression and metastasis by regulating the PTEN/AKT pathway and may serve as a novel prognostic predictor in patients with iCCA.

Risk factors for residual back pain following percutaneous vertebral augmentation: the importance of paraspinal muscle fatty degeneration.

PURPOSE: Residual back pain (RBP) after percutaneous vertebral augmentation (PVA) still exists considerable, and it even affects daily life due to moderate or severe back pain. A variety of risk factors have been previously identified for developing residual back pain. However, there are conflicting reports regarding the association between sarcopenia and residual back pain. As such, the aim of this study was to investigate whether paraspinal muscle fatty degeneration is a predictor of residual back pain. METHODS: We retrospectively reviewed the medical records of patients with single-segment OVCF who underwent PVA from January 2016 to January 2022. Patients were divided into RBP group (86 patients) and control group (790 patients) according to whether the visual analog scale (VAS) score ≥ 4. The clinical and radiological data were analyzed. Paraspinal musculature fatty degeneration was measured using the Goutallier classification system (GCS) at the L4 - 5 intervertebral disc level. Univariate and multivariate logistic regression analyses were performed to identify risk factors. RESULTS: The results of multivariate logistical regression analysis revealed that posterior fascia injury (odds ratio (OR) = 5.23; 95% confidence interval (CI) 3.12-5.50; P < 0.001), as regards paraspinal muscle fatty degeneration, including Goutallier grading (OR = 12.23; 95% CI 7.81-23.41; P < 0.001), fCSA (OR = 3.06; 95% CI 1.63-6.84; P = 0.002), fCSA/CSA (%) (OR = 14.38; 95% CI 8.80-26.29; P < 0.001), and facet joint violation (OR = 8.54; 95% CI 6.35-15.71; P < 0.001) were identified as independent risk factors for RBP. CONCLUSIONS: Posterior fascia injury, paraspinal muscle fatty degeneration, and facet joint violation were identified as independent risk factors for RBP, with paraspinal muscle fatty degeneration playing an important role.

Insights into SO2 Poisoning Mechanisms of Fresh and Hydrothermally Aged Cu-KFI Catalysts for NH3-SCR Reaction.

The complex poisoning of Cu-KFI catalysts by SO2 and hydrothermal aging (HTA) was investigated. The low-temperature activity of Cu-KFI catalysts was restrained by the formation of H2SO4 and then CuSO4 after sulfur poisoning. Hydrothermally aged Cu-KFI exhibited better SO2 resistance than fresh Cu-KFI since HTA significantly reduced the number of Brønsted acid sites, which were considered to be the H2SO4 storage sites. The high-temperature activity of SO2-poisoned Cu-KFI was basically unchanged compared to the fresh catalyst. However, SO2 poisoning promoted the high-temperature activity of hydrothermally aged Cu-KFI since it triggered CuOx into CuSO4 species, which was considered as an important role in the NH3-SCR reaction at high temperatures. In addition, hydrothermally aged Cu-KFI catalysts were more easily regenerated after SO2 poisoning than fresh Cu-KFI on account of the instability of CuSO4.

Hydrothermal Aging Alleviates the Phosphorus Poisoning of Cu-SSZ-39 Catalysts for NH3-SCR Reaction.

As a new type of catalyst with the potential for commercial application in NOx removal from diesel engine exhausts, Cu-SSZ-39 catalysts must have excellent resistance to complex and harsh conditions. In this paper, the effects of phosphorus on Cu-SSZ-39 catalysts before and after hydrothermal aging treatment were investigated. Compared with fresh Cu-SSZ-39 catalysts, phosphorus poisoning significantly decreased the low-temperature NH3-SCR catalytic activity. However, such activity loss was alleviated by further hydrothermal aging treatment. To reveal the reason for this interesting result, a variety of characterization techniques including NMR, H2-TPR, X-ray photoelectron spectroscopy, NH3-TPD, and in situ DRIFTS measurements were employed. It was found that Cu-P species produced by phosphorus poisoning decreased the redox ability of active copper species, resulting in the observed low-temperature deactivation. After hydrothermal aging treatment, however, Cu-P species partly decomposed with the formation of active CuOx species and a release of active copper species. As a result, the low-temperature NH3-SCR catalytic activity of Cu-SSZ-39 catalysts was recovered.

Circular RNAs in cholangiocarcinoma.

Cholangiocarcinoma (CCA) is the most common primary biliary malignancy with an adverse prognosis. Although its incidence is relatively low, early diagnosis is difficult due to the lack of specific symptoms. Current treatment options for CCA are limited, resulting in a low curative rate. Circular RNAs (circRNAs) have become a new research hotspot in recent years, and they are frequently dysregulated in CCA and may become therapeutic targets and prognostic biomarkers of CCA. Accumulating evidence has demonstrated that numerous dysregulated circRNAs are vital players in the etiopathogenesis of CCA. Aberrant expression of specific circRNAs was correlated with unfavourable clinical characteristics in CCA. Many studies have found that circRNAs are involved in the progression and development of CCA through various mechanisms, including competitive inhibition of miRNAs via the competing endogenous RNA (ceRNA) network, interaction with RNA-binding proteins (RBPs), activation of cancer-related signalling pathways, and regulation of proteins and peptides. Additionally, some circRNAs are involved in the inflammatory microenvironment of CCA and play a crucial role in chemotherapy drug resistance. Thus, they are essential for the early diagnosis and prediction of CCA, and more attention should be given to the roles and mechanisms of circRNAs in CCA. In this review, we summarize the abnormal expression of circRNAs in CCA and the specific inflammatory microenvironment involved, as well as the roles and mechanisms of circRNAs in the occurrence and development of CCA. We also review the latest knowle dge on circRNAs in CCA and discuss the challenges associated with the introduction of circRNAs into clinical practice and their potential clinical value.

Predictive Factors for Bone Cement Displacement following Percutaneous Vertebral Augmentation in Kümmell's Disease.

Objective: To investigate the independent influencing factors of bone cement displacement following percutaneous vertebral augmentation (PVA) in patients with stage I and stage II Kümmell's disease. Methods: We retrospectively reviewed the records of 824 patients with stage Ⅰ and stage Ⅱ Kümmell's disease treated with percutaneous vertebroplasty (PVP) or percutaneous vertebroplasty (PKP) from January 2016 to June 2022. Patients were divided into the postoperative bone cement displacement group (n = 150) and the bone cement non-displacement group (n = 674) according to the radiographic inspection results. The following data were collected: age, gender, body mass index (BMI), underlying disease, bone mineral density (BMD), involved vertebral segment, Kümmell's disease staging, anterior height, local Cobb angle, the integrity of anterior vertebral cortex, the integrity of endplate in surgical vertebrae, surgical method, surgical approach, the volume of cement, distribution of cement, the viscosity of cement, cement leakage, and postoperative anti-osteoporosis treatment. Binary logistic regression analysis was performed to determine the independent influencing factors of bone cement displacement. The discrimination ability was evaluated using the area under the curve (AUC) of the receiver operating characteristic (ROC). Results: The results of logistic regression analysis revealed that thoracolumbar junction (odds ratio (OR) = 3.23, 95% confidence interval (CI) 2.12−4.50, p = 0.011), Kümmell's disease staging (OR = 2.23, 95% CI 1.81−3.41, p < 0.001), anterior cortex defect (OR = 5.34, 95% CI 3.53−7.21, p < 0.001), vertebral endplates defect (OR = 0.54, 95% CI 0.35−0.71, p < 0.001), cement distribution (OR = 2.86, 95% CI 2.03−3.52, p = 0.002), cement leakage (OR = 4.59, 95% CI 3.85−5.72, p < 0.001), restoration of local Cobb angle (OR = 3.17, 95% CI 2.40−5.73, p = 0.024), and postoperative anti-osteoporosis treatment (OR = 0.48, 95% CI 0.18−0.72, p = 0.025) were independently associated with the bone cement displacement. The results of the ROC curve analysis showed that the AUC was 0.816 (95% CI 0.747−0.885), the sensitivity was 0.717, and the specificity was 0.793. Conclusion: Thoracolumbar fracture, stage Ⅱ Kümmell's disease, anterior cortex defect, uneven cement distribution, cement leakage, and high restoration of the local Cobb angle were risk factors for cement displacement after PVA in Kümmell's disease, while vertebral endplates defect and postoperative anti-osteoporosis treatment are protective factors.

Si/Al Ratio Determines the SCR Performance of Cu-SSZ-13 Catalysts in the Presence of NO2.

A comparative study was performed to investigate the NH3-selective catalytic reduction (SCR) reaction activity of Cu-SSZ-13 zeolites having Si/Al ratios (SARs) of 5, 18, and 30. Remarkably, the Cu-SSZ-13 zeolite catalysts exhibited completely opposite behaviors as a function of SAR under standard SCR (SSCR) and fast SCR (FSCR) reaction atmospheres. Under SSCR conditions, the NOx conversion increased as expected with the decreasing SAR. Under FSCR conditions, however, the NOx conversion decreased as the SAR decreased, contrary to expectations. In this study, based on characterization of the catalysts by X-ray diffraction, transmission electron microscopy, electron paramagnetic resonance, H2-temperature-programmed reduction, temperature-programmed desorption, and diffuse reflectance infrared Fourier transform spectroscopy, together with theoretical calculations, the authors found that the amount of Brønsted acid sites goes up while the SAR goes down, leading to an increase in the accumulation of NH4NO3 under FSCR reaction conditions. Moreover, the accumulated NH4NO3 is of greater stability for those low SAR Cu-SSZ-13 catalysts. These two reasons cause the FSCR performance of Cu-SSZ-13 to decrease with a decrease in SAR. As a result, the NO2 effect on SCR activity changes from promotion to inhibition as the SAR decreases.

Epidemiological characteristics of traumatic spinal cord injuries in a multicenter retrospective study in northwest China, 2017-2020.

Background: Traumatic spinal cord injuries (TSCIs) are worldwide public health problems that are difficult to cure and impose a substantial economic burden on society. There has been a lack of extensive multicenter review of TSCI epidemiology in northwest China during the Corona Virus Disease 2019 (COVID-19) pandemic. Method: A multicenter retrospective study of 14 selected hospitals in two provinces in northwest China was conducted on patients admitted for TSCI between 2017 and 2020. Variables assessed included patient demographics, etiology, segmental distribution, treatment, waiting time for treatment, and outcomes. Results: The number of patients with TSCI showed an increasing trend from 2017 to 2019, while there were 12.8% fewer patients in 2020 than in 2019. The male-to-female ratio was 3.67:1, and the mean age was 48 ± 14.9 years. The primary cause of TSCI was high falls (38.8%), slip falls/low falls (27.7%), traffic accidents (23.9%), sports (2.6%), and other factors (7.0%). The segmental distribution showed a bimodal pattern, peak segments were C6 and L1 vertebra, L1 (14.7%), T12 (8.2%), and C6 (8.2%) were the most frequently injured segments. In terms of severity, incomplete injury (72.8%) occurred more often than complete injury (27.2%). The American Spinal Injury Association impairment scale of most patients did not convert before and after treatment in the operational group (71.6%) or the conservative group (80.6%). A total of 975 patients (37.2%) from urban and 1,646 patients (62.8%) from rural areas were included; almost all urban residents could rush to get treatment after being injured immediately (<1 h), whereas most rural patients get the treatment needed 4-7 h after injury. The rough annual incidence from 2017 to 2020 is 112.4, 143.4, 152.2, and 132.6 per million people, calculated by the coverage rate of the population of the sampling hospital. Conclusion: The incidence of TSCI in northwest China is high and on the rise. However, due to pandemic policy reasons, the incidence of urban residents decreased in 2020. The promotion of online work may be an effective primary prevention measure for traumatic diseases. Also, because of the further distance from the good conditional hospital, rural patients need to spend more time there, and the timely treatment of patients from remote areas should be paid attention to.