Digital finance, financial regulation and transformation of R&D achievements.

The transformation of scientific and technological achievements is the best form of the combination of technology and the economy, and only when new technologies are transformed into commodities can they be transformed into real productive forces and exert scale effects. With the rapid development of digital finance, it has changed the operating mode of financial markets and consumer behavior. Does digital finance promote the transformation of R&D achievements? We empirically examine this question using the panel data covering 30 provinces in China from 2011 to 2021. The empirical results indicate that the development of digital finance can improve the transformation rate of R&D achievements. Additionally, we find that the role of digital finance in promoting the transformation of R&D achievements needs to be guaranteed by the level of effective financial regulation. The research conclusions are a relevant reference for the government to improve the transformation rate of scientific and technological achievements.

Ab Initio Driven Exploration on the Thermal Properties of Al-Li Alloy.

Al-Li alloys are feasible and promising additives in advanced energy and propellant systems due to the significantly enhanced heat release and increased specific impulse. The thermal properties of Al-Li alloys directly determine the manufacturing, storage safety, and ignition delay of propellants. In this study, a neural network potential (NNP) is developed to investigate the thermal behaviors of Al-Li alloys from an atomistic perspective. The novel NNP demonstrates an excellent predictive ability for energy, atomic force, mechanical behaviors, phonon vibrations, and dynamic evolutions. A series of NNP-based molecular dynamics simulations are performed to investigate the effect of Li doping on the thermal properties of Al-Li alloys. All calculated results for Al-Li alloys are consistent with experimental values for Al, ensuring their validity in predicting Al-Li interactions. The simulation results suggest that a minor increment in the Li content results in a slight change in the melting point, thermal expansion, and radical distribution functions. These three properties are associated with the lattice characteristics; nonetheless, it causes a substantial reduction in thermal conductivity, which is related to the physical properties of the elements. The lower thermal conductivity allows heat accumulation on the particle surface, thereby speeding up the surface premelt and ignition. This provides an alternative atomic explanation for the improved combustion performance of Al-Li alloys. These findings integrate insights from the field of alloy material science into crucial combustion applications, serving as an atomistic guide for developing manufacturing techniques.

Genome-Wide Analysis of Family-1 UDP-Glycosyltransferases in Potato (Solanum tuberosum L.): Identification, Phylogenetic Analysis and Determination of Response to Osmotic Stress.

Family-1 UDP-glycosyltransferases (UGTs) are the most common and functional glycosyltransferases in the plant world. UGT is closely related to plant growth and the response to abiotic stress. However, despite systematic research, our understanding of potato UGT genes is still unclear. In this study, we identified 174 potato UGT proteins based on their conserved plant secondary product glycosyltransferase (PSPG) motifs. Phylogenetic analyses were used to compare these proteins with Arabidopsis UGTs and other plant UGTs, and it was found that they could be clustered into 18 distinct groups. Patterns of intron gain/loss and intron phases within potato UGTs revealed highly conserved intron insertion events. The promoter cis-elements of these 174 UGT genes were systematically investigated. The promoter regions of these UGT genes are known to contain various classes of cis-acting compounds. These include elements that are light-responsive, phytohormone-responsive, and stress-responsive. Transcriptome data analysis established that 25, 10, 6, and 4 of these 174 UGT genes were specifically expressed in leaves, roots, stolons, and young tubers, respectively. The mannitol-treated transcriptomic data showed thirty-eight UGT genes were significantly upregulated. The quantitative real-time PCR results showed that the four genes were all responsive to osmotic stress under a 10% PEG6000 treatment. The results of our study provide a basis for clarifying the molecular mechanism of potato osmotic stress resistance and better understanding its function in the future.

Unraveling Anisotropy in Crystalline Orientation under Shock-Induced Dynamic Responses in High-Entropy Alloy Co25Ni25Fe25Al7.5Cu17.5.

Shock-induced plastic deformation and spall damage in the single-crystalline FCC Co25Ni25Fe25Al7.5Cu17.5 high-entropy alloy (HEA) under varying shock intensities were systematically investigated using large-scale molecular dynamics simulations. The study reveals the significant influence of crystalline orientation on the deformation mechanism and spall damage. Specifically, the shock wave velocities in the [110] and [111] directions are significantly higher than that in the [001] direction, resulting in a two-zone elastic-plastic shock wave structure observed in the [110] and [111] samples, while only a single-wave structure is found in the [001] sample. The plastic deformation is dominated by the FCC to BCC transformation following the Bain path and a small amount of stacking faults during the compression stage in the [001] sample, whereas it depends on the stacking faults induced by Shockley dislocation motion in the [110] and [111] samples. The stacking faults and phase transformation in the [001] sample exhibit high reversibility under release effects, while extensive dislocations are present in the [110] and [111] samples after release. Interestingly, tension-strain-induced FCC to BCC phase transformation is observed in the [001] sample during the release stage, resulting in increased spall strength compared to the [110] and [111] samples. The spall strength estimated from both bulk and free surface velocity history shows reasonable consistency. Additionally, the spall strength remains stable with increasing shock intensities. The study discusses in detail the shock wave propagation, microstructure change, and spall damage evolution. Overall, our comprehensive studies provide deep insights into the deformation and fracture mechanisms of Co25Ni25Fe25Al7.5Cu17.5 HEA under shock loading, contributing to a better understanding of dynamic deformation under extreme environments.

Conservative treatment of hepatic portal vein gas after transarterial chemoembolization treatment for liver metastasis of postoperative esophageal cancer: a case report.

Background: Hepatic portal vein gas (HPVG), which is a rare clinical manifestation, is usually considered a sign of critical illness. If the treatment is not timely, it will lead to intestinal ischemia, intestinal necrosis, and even death. There is still no consensus on whether to adopt surgical or conservative treatment for HPVG. Herein, we report a rare case of conservative treatment of HPVG after transarterial chemoembolization (TACE) treatment in a patient with liver metastasis of postoperative esophageal cancer, who received long-term enteral nutrition (EN). Case Description: A 69-year-old male patient, who had undergone surgery for esophageal cancer, needed long-term use of jejunal feeding tube implantation for enteral nutritional support due to postoperative complications. About 9 months after the operation, multiple metastases of the liver were detected. To control the progress of the disease, TACE was conducted. EN was restored on the second day after TACE, and the patient was discharged on the fifth day. On the night of discharge, the patient suddenly experienced abdominal pain, nausea, and vomiting. Abdominal computed tomography (CT) showed that the abdominal intestinal lumen was obviously dilated, liquid and gas plane shadowing was visible, and gas was visible in the portal vein and its branches. The physical examination showed that peritoneal irritation was present, and bowel sounds were active. Blood routine examination showed an increase in neutrophil and neutrophil. Symptomatic treatment, including gastrointestinal decompression, anti-infection, and parenteral nutritional support, was provided. On the third day after the presentation of HPVG, abdominal CT reexamination showed that HPVG had disappeared and the intestinal obstruction was relieved. Repeated blood routine shows a decrease in neutrophil and neutrophil. Conclusions: Elderly patients who require long-term EN support should avoid early EN support after TACE, as this can prevent intestinal obstruction and HPVG. If the patient suddenly experiences abdominal pain after TACE, CT scan should be performed in a timely manner to determine whether there is intestinal obstruction and HPVG. If the above type of patient experiences HPVG, conservative treatments such as early gastrointestinal decompression, fasting, and anti-infection treatment can be provided first without high-risk factors.

Fasudil inhibits hepatic artery spasm by repressing the YAP/ERK/ ETA/ETB signaling pathway via inhibiting ROCK activation.

OBJECTIVE: To explore the effect of Fasudil on HA spasm and its underlying mechanism. METHODS: Rabbits were divided into Sham, Fasudil, and Model groups for experiments. Fasudil was injected into the left medial lobe of the rabbit liver using a 16G lumbar puncture needle through the laparotomic route. The spasm model was established by inserting the catheter sheath into the femoral arteries of rabbits, followed by celiac artery angiography and left HA catheterization with a micro-catheter. Next, the GSE60887 and GSE37924 datasets concerning Fasudil treatment were analyzed. Moreover, immunofluorescence staining was conducted for YAP1 and α-SMA. Finally, Western blotting was performed to examine the expressions of YAP1, ROCK, ERK1/2, ETA, and ETB. RESULTS: Fasudil could relieve HA spasm. The Go and KEGG pathway analyses revealed that the MAPK signaling pathway and the Hippo signaling pathway were enriched in vasospasm. Besides, GSEA revealed that ROCK was functionally enriched in the MAPK and Hippo signaling pathways. Co-expression analysis revealed that MAPK1 was significantly correlated with YAP1 and MYC, and YAP1 was significantly correlated with ETA and ETB. It was manifested in the results of immunofluorescence staining that the YAP1-positive fluorescence area was significantly decreased after Fasudil treatment. Moreover, Western blotting results showed that Fasudil decreased the expressions of YAP1, RhoA, ROCK, ETA, ETB, and p-ERK1/2. In addition, in-vitro Western blotting revealed that Fasudil suppressed the YAP/ERK/ETA/ETB signaling pathway in the case of HA spasm by inhibiting ROCK activation. CONCLUSIONS: Fasudil ameliorates HA spasm through suppressing the YAP/ERK/ETA/ETB signaling pathway and the ROCK activation.

Nephroprotective effect of magnesium isoglycyrrhizinate against arsenic trioxide-induced acute kidney damage in mice.

Magnesium isoglycyrrhizinate (MgIG) has anti-inflammatory, antioxidative, antiviral and anti-hepatotoxic effects. However, protective effects of MgIG against renal damage caused by arsenic trioxide (ATO) have not been reported. The present study aimed to clarify the protective function of MgIG on kidney damaged induced by ATO. Other than the control group and the group treated with MgIG alone, mice were injected intraperitoneally with ATO (5 mg/kg/day) for 7 days to establish a mouse model of kidney damage. On the 8th day, blood and kidney tissue were collected and the inflammatory factors and antioxidants levels in the kidney tissue and serum were measured. The expression of protein levels of caspase-3, Bcl-2, Bax, Toll-like receptor-4 (TLR4) and nuclear factor-κB (NF-κB) were determined via western blot analysis. In the renal tissue of mice, ATO exposure dramatically elevated markers of oxidative stress, apoptosis and inflammation. However, MgIG could also restore the activities of urea nitrogen and creatinine to normal levels, decrease the malondialdehyde level and reactive oxygen species formation and increase superoxide dismutase, catalase and glutathione activities. MgIG also ameliorated the morphological abnormalities generated by ATO, reduced inflammation and apoptosis and inhibited the TLR4/NF-κB signaling pathway. In conclusion, MgIG may mitigate ATO-induced kidney damage by decreasing apoptosis, oxidative stress and inflammation and its mechanism may be connected to the inhibition of TLR4/NF-κB signaling.

Exploring the Mechanism of Danshensu in the Treatment of Doxorubicin-Induced Cardiotoxicity Based on Network Pharmacology and Experimental Evaluation.

Background: Doxorubicin (DOX) is one of the most effective chemotherapeutic agents available; however, its use is limited by the risk of serious cardiotoxicity. Danshensu (DSS), an active ingredient in Salvia miltiorrhiza, has multiple cardioprotective effects, but the effect of DSS on DOX-induced cardiotoxicity has not been reported. Objectives: Predicting the targets of DOX-induced cardiotoxicity and validating the protective effects and mechanisms of DSS. Methods: (1) Using methods based on network pharmacology, DOX-induced cardiotoxicity was analyzed by data analysis, target prediction, PPI network construction and GO analysis. (2) The cardiotoxicity model was established by continuous intraperitoneal injection of 15 mg/kg of DOX into mice for 4 days and the protective effects and mechanism were evaluated by treatment with DSS. Results: The network pharmacology results indicate that CAT, SOD, GPX1, IL-6, TNF, BAX, BCL-2, and CASP3 play an important role in this process, and Keap1 is the main target of DOX-induced cardiac oxidative stress. Then, based on the relationship between Keap1 and Nrf2, the Keap1-Nrf2/NQO1 pathway was confirmed by animal experiments. In the animal experiments, by testing the above indicators, we found that DSS effectively reduced oxidative stress, inflammation, and apoptosis in the damaged heart, and significantly alleviated the prolonged QTc interval caused by DOX. Moreover, compared with the DOX group, DSS elevated Keap1 content and inhibited Nrf2, HO-1, and NQO1. Conclusion: The results of network pharmacology studies indicated that Keap1-Nrf2/NQO1 is an important pathway leading to DOX-induced cardiotoxicity, and the results of animal experiments showed that DSS could effectively exert anti-oxidative stress, anti-inflammatory and anti-apoptotic therapeutic effects on DOX-induced cardiotoxicity by regulating the expression of Keap1-Nrf2/NQO1.

Kindlin-2 inhibits Nlrp3 inflammasome activation in nucleus pulposus to maintain homeostasis of the intervertebral disc.

Intervertebral disc (IVD) degeneration (IVDD) is the main cause of low back pain with major social and economic burdens; however, its underlying molecular mechanisms remain poorly defined. Here we show that the focal adhesion protein Kindlin-2 is highly expressed in the nucleus pulposus (NP), but not in the anulus fibrosus and the cartilaginous endplates, in the IVD tissues. Expression of Kindlin-2 is drastically decreased in NP cells in aged mice and severe IVDD patients. Inducible deletion of Kindlin-2 in NP cells in adult mice causes spontaneous and striking IVDD-like phenotypes in lumbar IVDs and largely accelerates progression of coccygeal IVDD in the presence of abnormal mechanical stress. Kindlin-2 loss activates Nlrp3 inflammasome and stimulates expression of IL-1ß in NP cells, which in turn downregulates Kindlin-2. This vicious cycle promotes extracellular matrix (ECM) catabolism and NP cell apoptosis. Furthermore, abnormal mechanical stress reduces expression of Kindlin-2, which exacerbates Nlrp3 inflammasome activation, cell apoptosis, and ECM catabolism in NP cells caused by Kindlin-2 deficiency. In vivo blocking Nlrp3 inflammasome activation prevents IVDD progression induced by Kindlin-2 loss and abnormal mechanical stress. Of translational significance, adeno-associated virus-mediated overexpression of Kindlin-2 inhibits ECM catabolism and cell apoptosis in primary human NP cells in vitro and alleviates coccygeal IVDD progression caused by mechanical stress in rat. Collectively, we establish critical roles of Kindlin-2 in inhibiting Nlrp3 inflammasome activation and maintaining integrity of the IVD homeostasis and define a novel target for the prevention and treatment of IVDD.

Protective effect of baicalin against arsenic trioxide-induced acute hepatic injury in mice through JAK2/STAT3 signaling pathway.

Baicalin (BA) is a kind of flavonoid that is isolated from Scutellaria baicalensis Georgi, which has been verified to have hepatoprotective effects in some diseases. However, the role of BA in acute hepatic injury induced by arsenic trioxide (ATO) remains unclear. The aim of this study was to investigate the protective action of BA on acute hepatic injury induced by ATO and to probe its possible mechanism. Mice were pretreated with BA (50, 100 mg/kg) by gavage. After 7 h, ATO (7.5 mg/kg) was injected intraperitoneally to induce liver injury. After 7 days of treatment, serum and hepatic specimens were collected and assayed to evaluate the hepatoprotective effect of BA. Pathological sections and the liver function index indicated that ATO caused significant liver injury. The fluorescence of reactive oxygen species and oxidative stress indicators showed that ATO also increased oxidative stress. The inflammatory markers in ATO-induced mice also increased significantly. Staining of the terminal deoxynucleotidyl transferase dUTP nick end labeling and apoptotic factor assay showed that apoptosis increased. However, with BA pretreatment, these changes were significantly weakened. In addition, BA treatment promoted the expression of proteins related to the JAK2/STAT3 signaling pathway. The results suggest that BA can ameliorate acute ATO-induced hepatic injury in mice, which is related to the inhibition of oxidative stress, thereby reducing inflammation and apoptosis. The mechanism of this protection is potentially related to the JAK2/STAT3 signaling pathway.

Explainable AI for Data-Driven Feedback and Intelligent Action Recommendations to Support Students Self-Regulation.

Formative feedback has long been recognised as an effective tool for student learning, and researchers have investigated the subject for decades. However, the actual implementation of formative feedback practices is associated with significant challenges because it is highly time-consuming for teachers to analyse students' behaviours and to formulate and deliver effective feedback and action recommendations to support students' regulation of learning. This paper proposes a novel approach that employs learning analytics techniques combined with explainable machine learning to provide automatic and intelligent feedback and action recommendations that support student's self-regulation in a data-driven manner, aiming to improve their performance in courses. Prior studies within the field of learning analytics have predicted students' performance and have used the prediction status as feedback without explaining the reasons behind the prediction. Our proposed method, which has been developed based on LMS data from a university course, extends this approach by explaining the root causes of the predictions and by automatically providing data-driven intelligent recommendations for action. Based on the proposed explainable machine learning-based approach, a dashboard that provides data-driven feedback and intelligent course action recommendations to students is developed, tested and evaluated. Based on such an evaluation, we identify and discuss the utility and limitations of the developed dashboard. According to the findings of the conducted evaluation, the dashboard improved students' learning outcomes, assisted them in self-regulation and had a positive effect on their motivation.

Atomistic Simulations on Metal Rod Penetrating Thin Target at Nanoscale Caused by High-Speed Collision.

The penetration process has attracted increasing attention due to its engineering and scientific value. In this work, we investigate the deformation and damage mechanism about the nanoscale penetration of single-crystal aluminum nanorod with atomistic simulations, where distinct draw ratio (∅) and different incident velocities (up) are considered. The micro deformation processes of no penetration state (within 2 km/s) and complete penetration (above 3 km/s) are both revealed. The high-speed bullet can cause high pressure and temperature at the impacted region, promoting the localized plastic deformation and even solid-liquid phase transformation. It is found that the normalized velocity of nanorod reduces approximately exponentially during penetration (up < 3 km/s), but its residual velocity linearly increased with initial incident velocity. Moreover, the impact crater is also calculated and the corresponding radius is manifested in the linear increase trend with up while inversely proportional to the ∅. Interestingly, the uniform fragmentation is observed instead of the intact spallation, attributed to the relatively thin thickness of the target. It is additionally demonstrated that the number of fragments increases with increasing up and its size distribution shows power law damping nearly. Our findings are expected to provide the atomic insight into the micro penetration phenomena and be helpful to further understand hypervelocity impact related domains.

Liquiritigenin protects against arsenic trioxide-induced liver injury by inhibiting oxidative stress and enhancing mTOR-mediated autophagy.

Liquiritigenin (LQ) has protective effects against various hepatotoxicities. However, its specific role on arsenic trioxide (ATO)-induced hepatotoxicity and the related biomolecular mechanisms remain unclear. The purpose of this study is to explore the protective actions of LQ on ATO-induced hepatotoxicity and its biomolecular mechanisms in mice. LQ was administered orally at 20 and 40 mg/kg per day for seven consecutive days with an intraperitoneal injection of ATO (5 mg/kg). Liver injury was induced by ATO and was alleviated by treatment with LQ as reflected by reduced histopathological damage of liver and decreased serum ALT, AST, and ALP levels. The generation of intracellular ROS induced by ATO was attenuated after LQ treatment. The levels of SOD, CAT, and GSH were elevated with LQ administration while MDA levels decreased. LQ mitigated elevated TNF-α and IL-6 levels as well as the hepatic mitochondrial damage caused by ATO. Moreover, LQ upregulated the expression of LC3-II and enhanced autophagy in the liver of ATO-induced mice. Further studies indicated that LQ significantly suppressed the expression of p-PI3K, p-AKT, and p-mTOR in ATO-induced mice. In conclusion, our findings show that LQ protects against ATO-induced hepatotoxicity due to its antioxidant and anti-inflammatory activities and enhancement of autophagy mediated by the PI3K/AKT/mTOR signaling pathway in mice.

Distribution of bacteria infected by metagenomic sequencing technology in maxillofacial space.

OBJECTIVES: This study aimed to compare and analyze the consistency and difference between metageno-mic next-generation sequencing (mNGS) and conventional bacterial culture in the detection of pathogenic microorganisms in maxillofacial space infection, as well as to provide a new detection method for the early clinical identification of pathogenic bacteria in maxillofacial space infection. METHODS: The clinical data of 16 patients with oral and maxillofacial space infections in the First Affiliated Hospital of Zhengzhou University from March 2020 to June 2020 were collected. mNGS and conventional bacterial culture methods were used to detect pus. We then analyzed and compared the test results of the two methods, including the test cycle, positive detection rate, anaerobic bacteria, facultative anaerobes and aerobic bacteria detection rates, distribution of pathogenic bacteria, relative species abundance, and resistance genes. RESULTS: The average inspection period of mNGS was (18.81±3.73) h, and the average inspection period of bacterial culture was (83.25±11.64) h, the former was shorter than the latter (P<0.05). The positive detection rate of mNGS was 100% (16/16), and the positive detection rate of conventional bacterial culture was 31.25% (5/16), the former was higher than the latter (P<0.05). The detection rate of mNGS anaerobic bacteria was 93.75% (15/16), the detection rate of bacterial culture anaerobes was 0 (0/16), the former was higher than the latter (P<0.05). Using mNGS, the detection rate of facultative anaerobes in bacterial culture was 75.00% (12/16), and the detection rate of facultative anaerobes in bacterial culture was 25.00% (4/16), the former was higher than the latter (P<0.05). The detection rate of aerobic bacteria in bacterial culture was 12.50% (1/16), the former was higher than the latter (P>0.05). mNGS detected 15 kinds of pathogenic bacteria, among which 3 were Gram positive, 12 were Gram negative, 49 were non-pathogenic, 16 were Gram positive, and 32 were Gram negative, 1 was fungus. CONCLUSIONS: Compared with conventional bacterial culture, mNGS has the characteristics of short test time, high sensitivity, and high accuracy. Thus, it is a new detection method for the early identification of pathogenic bacteria in maxillofacial space infection and is beneficial to the early clinical diagnosis and treatment of the disease.

Investigation of the ameliorative effects of baicalin against arsenic trioxide-induced cardiac toxicity in mice.

Baicalin (BA), a kind of flavonoids compound, comes from Scutellaria baicalensis Georgi (a kind of perennial herb) and has beneficial effects on the cardiovascular system through anti-oxidant, anti-inflammation, and anti-apoptosis actions. However, the therapeutic effects and latent mechanisms of BA on arsenic trioxide (ATO)-induced cardiac toxicity has not been reported. The present research was performed to explore the effects and mechanisms of BA on ATO-induced heart toxicity. Male Kunming mice were treated with ATO (7.5 mg/kg) to induce cardiac toxicity. After the mice received ATO, BA (50 and 100 mg/kg) was administered for estimating its cardioprotective effects. Statistical data demonstrated that BA treatment alleviated electrocardiogram abnormalities and pathological injury caused by ATO. BA could also lead to recovery of CK and LDH activities to normal range and cause a decrease in MDA levels and ROS generation, augmentation of SOD, CAT, and GSH activities. We also found that BA caused a reduction in the expression of proinflammatory cytokines, such as TNF-α and IL-6. Moreover, BA attenuated ATO-induced apoptosis by promoting the expression of Bcl-2 and suppressing the expression of Bax and caspase-3. TUNEL test result demonstrated BA caused impediment of ATO-induced apoptosis. Furthermore, BA treatment suppressed the high expression of TLR4, NF-κB and P-NF-κB caused by ATO. In conclusion, these results indicate that BA may alleviate ATO-induced cardiac toxicity by restraining oxidative stress, apoptosis, and inflammation, and its mechanism would be associated with the inhibition of the TLR4/NF-κB signaling pathway.

HIF1A Alleviates compression-induced apoptosis of nucleus pulposus derived stem cells via upregulating autophagy.

Intervertebral disc degeneration (IDD) is the primary pathological mechanism that underlies low back pain. Overloading-induced cell death, especially endogenous stem cell death, is the leading factor that undermines intrinsic repair and aggravates IDD. Previous research has separately studied the effect of oxygen concentration and mechanical loading in IDD. However, how these two factors synergistically influence endogenous repair remains unclear. Therefore, we established in vitro and in vivo models to study the mechanisms by which hypoxia interacted with overloading-induced cell death of the nucleus pulposus derived stem cells (NPSCs). We found the content of HIF1A (hypoxia inducible factor 1 subunit alpha) and the number of NPSCs decreased with disc degeneration in both rats and human discs. Hence, we isolated this subpopulation from rat discs and treated them simultaneously with hypoxia and excessive mechanical stress. Our results demonstrated that hypoxia exerted protective effect on NPSCs under compression, partially through elevating macroautophagy/autophagy. Proteomics and knockdown experiments further revealed HIF1A-BNIP3-ATG7 axis mediated the increase in autophagy flux, in which HMOX1 and SLC2A1 were also involved. Moreover, HIF1A-overexpressing NPSCs exhibited stronger resistance to over-loading induced apoptosis in vitro. They also showed higher survival rates, along with elevated autophagy after being intra-disc transplanted into over-loaded discs. Jointly, both in vivo and in vitro experiments proved the anti-apoptotic effect of HIF1A on NPSCs under the excessive mechanical loading, suggesting that restoring hypoxia and manipulating autophagy is crucial to maintain the intrinsic repair and to retard disc degeneration.Abbreviations: 3-MA: 3-methyladenine; ACAN: aggrecan; ATG7: autophagy related 7; BafA1: bafilomycin A1; BAX: BCL2 associated X, apoptosis regulator; BECN1: beclin 1; BNIP3: BCL2 interacting protein 3; BNIP3L: BCL2 interacting protein 3 like; CASP3: caspase 3; CCK8: cell counting kit-8; CHT: chetomin; CMP: compression; CoCl2: cobalt chloride; COL2A1: collagen type II alpha 1 chain; Ctrl: control; DAPI: 4,6-diamidino-2-phenylindole; DEP: differentially expressed protein; DiR: 1,1-dioctadecyl-3,3,3,3-tetramethyl indotricarbocyanine; ECM: extracellular matrix; FCM: flow cytometry; GD2: disialoganglioside GD 2; GFP: green fluorescent protein; GO: gene ontology; GSEA: gene set enrichment analysis; H&E: hematoxylin-eosin; HIF1A: hypoxia inducible factor 1 subunit alpha; HK2: hexokinase 2; HMOX1: heme oxygenase 1; HX: hypoxia mimicry; IDD: intervertebral disc degeneration; IF: immunofluorescence; IHC: immunohistochemistry; IVD: intervertebral disc; KEGG: kyoto encyclopedia of genes and genomes; LBP: low back pain; Lv: lentivirus; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MMP: mitochondrial membrane potential; NC: negative control; NIR: near-infrared; NP: nucleus pulposus; NPC: nucleus pulposus cell; NPSC: nucleus pulposus derived stem cell; NX: normoxia; PPI: protein-protein interactions; RFP: red fluorescent protein; SLC2A1/GLUT1: solute carrier family 2 member 1; SQSTM1/p62: sequestosome 1; TEK/TIE2: TEK receptor tyrosine kinase; TEM: transmission electron microscopy; TUBB: tubulin beta class I.

Local Delivery of Taxol From FGL-Functionalized Self-Assembling Peptide Nanofiber Scaffold Promotes Recovery After Spinal Cord Injury.

Taxol has been clinically approved as an antitumor drug, and it exerts its antitumor effect through the excessive stabilization of microtubules in cancer cells. Recently, moderate microtubule stabilization by Taxol has been shown to efficiently promote neurite regeneration and functional recovery after spinal cord injury (SCI). However, the potential for the clinical translation of Taxol in treating SCI is limited by its side effects and low ability to cross the blood-spinal cord barrier (BSCB). Self-assembled peptide hydrogels have shown potential as drug carriers for the local delivery of therapeutic agents. We therefore hypothesized that the localized delivery of Taxol by a self-assembled peptide scaffold would promote axonal regeneration by stabilizing microtubules during the treatment of SCI. In the present study, the mechanistic functions of the Taxol-releasing system were clarified in vitro and in vivo using immunofluorescence labeling, histology and neurobehavioral analyses. Based on the findings from the in vitro study, Taxol released from a biological functionalized SAP nanofiber scaffold (FGLmx/Taxol) remained active and promoted neurite extension. In this study, we used a weight-drop contusion model to induce SCI at T9. The local delivery of Taxol from FGLmx/Taxol significantly decreased glial scarring and increased the number of nerve fibers compared with the use of FGLmx and 5% glucose. Furthermore, animals administered FGLmx/Taxol exhibited neurite preservation, smaller cavity dimensions, and decreased inflammation and demyelination. Thus, the local delivery of Taxol from FGLmx/Taxol was effective at promoting recovery after SCI and has potential as a new therapeutic strategy for SCI.

Inhibiting Heat Shock Protein 90 Protects Nucleus Pulposus-Derived Stem/Progenitor Cells From Compression-Induced Necroptosis and Apoptosis.

Nucleus pulposus-derived stem/progenitor cells (NPSCs) provide novel prospects for the regeneration of degenerated intervertebral disc (IVD). Nevertheless, with aging and degeneration of IVD, the frequency of NPSCs markedly decreases. Excessive cell death could be the main reason for declined frequency of NPSCs, however, the exact mechanisms remain elusive. Thus, the present study was undertaken to explore the mechanisms of compression-induced NPSCs death, and the effects of heat shock protein 90 (HSP90) on NPSCs survival. Here, we found that compression could trigger receptor-interacting protein kinase 1 (RIPK1)/receptor-interacting protein kinase 3 (RIPK3)/mixed lineage kinase domain-like protein (MLKL)-mediated necroptosis of NPSCs. Furthermore, we found that elevated expression of HSP90 was involved in compression-induced NPSCs death, and inhibiting HSP90 could dramatically attenuate compression-induced necroptosis of NPSCs via regulating the expression and activity of RIPK1/RIPK3/MLKL, and alleviating the mitochondrial dysfunction (mitochondrial membrane potential loss and ATP depletion) and oxidative stress [production of mitochondrial reactive oxygen species (ROS), cellular total ROS and malondialdehyde, and downregulation of superoxide dismutase 2]. Besides necroptosis, compression-induced apoptosis of NPSCs was also attenuated by HSP90 inhibition. In addition, we found that enhanced expression of HSP70 contributed to the cytoprotective effects of inhibiting HSP90. More encouragingly, our results demonstrated that inhibiting HSP90 could also mitigate the exhaustion of NPSCs in vivo. In conclusion, RIPK1/RIPK3/MLKL-mediated necroptosis participates in compression-induced NPSCs death. Furthermore, targeting HSP90 to simultaneously inhibit necroptosis and apoptosis of NPSCs might be an efficient strategy for preventing the death of NPSCs, thus rescuing the endogenous repair capacity of NP tissue.

Survey of COVID-19 Disease Among Orthopaedic Surgeons in Wuhan, People's Republic of China.

BACKGROUND: Coronavirus disease 2019 (COVID-19) broke out in Wuhan, the People's Republic of China, in December 2019 and now is a pandemic all around the world. Some orthopaedic surgeons in Wuhan were infected with COVID-19. METHODS: We conducted a survey to identify the orthopaedic surgeons who were infected with COVID-19 in Wuhan. A self-administered questionnaire was distributed to collect information such as social demographic variables, clinical manifestations, exposure history, awareness of the outbreak, infection control training provided by hospitals, and individual protection practices. To further explore the possible risk factors at the individual level, a 1:2 matched case-control study was conducted. RESULTS: A total of 26 orthopaedic surgeons from 8 hospitals in Wuhan were identified as having COVID-19. The incidence in each hospital varied from 1.5% to 20.7%. The onset of symptoms was from January 13 to February 5, 2020, and peaked on January 23, 8 days prior to the peak of the public epidemic. The suspected sites of exposure were general wards (79.2%), public places at the hospital (20.8%), operating rooms (12.5%), the intensive care unit (4.2%), and the outpatient clinic (4.2%). There was transmission from these doctors to others in 25% of cases, including to family members (20.8%), to colleagues (4.2%), to patients (4.2%), and to friends (4.2%). Participation in real-time training on prevention measures was found to have a protective effect against COVID-19 (odds ratio [OR], 0.12). Not wearing an N95 respirator was found to be a risk factor (OR, 5.20 [95% confidence interval (CI), 1.09 to 25.00]). Wearing respirators or masks all of the time was found to be protective (OR, 0.15). Severe fatigue was found to be a risk factor (OR, 4 [95% CI, 1 to 16]) for infection with COVID-19. CONCLUSIONS: Orthopaedic surgeons are at risk during the COVID-19 pandemic. Common places of work could be contaminated. Orthopaedic surgeons have to be more vigilant and take more precautions to avoid infection with COVID-19. LEVEL OF EVIDENCE: Diagnostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Pioglitazone Protects Compression-Mediated Apoptosis in Nucleus Pulposus Mesenchymal Stem Cells by Suppressing Oxidative Stress.

Excessive compression, the main cause of intervertebral disc (IVD) degeneration, affected endogenous repair of the intervertebral disc. Pioglitazone (PGZ) is the agonist of peroxisome proliferator-activated receptor γ, which has been widely used in the treatment of diabetes mellitus. The present study aim at investigating whether pioglitazone has protective effects on compression-mediated cell apoptosis in nucleus pulposus mesenchymal stem cells (NP-MSCs) and further exploring the possible underlying mechanism. Our results indicated that the isolated cells satisfied the criteria of MSC stated by the International Society for Cellular Therapy. Besides, our research revealed that pioglitazone could protect cell viability, cell proliferation of NP-MSCs and alleviated the toxic effects caused by compression. The actin stress fibers was suppressed obviously under compression, and pioglitazone alleviated the adverse outcomes. Pioglitazone exerted protective effects on compression-induced NP-MSCs apoptosis according to annexin V/PI double-staining and TUNEL assays. Pioglitazone suppressed compression-induced NP-MSCs oxidative stress, including decreasing compression-induced overproduction of reactive oxygen species (ROS) and malondialdehyde (MDA), and alleviated compression-induced mitochondrial membrane potential (MMP) decrease. Ultrastructure collapse of the mitochondria exhibited a notable improvement by pioglitazone in compression-induced NP-MSCs according to transmission electron microscopy (TEM). Furthermore, the molecular results showed that pioglitazone significantly decreased the expression of apoptosis-associated proteins, including cyto.cytochrome c, Bax, cleaved caspase-9, and cleaved caspase-3, and promoted Bcl-2 expression. These results indicated that pioglitazone alleviated compression-induced NP-MSCs apoptosis by suppressing oxidative stress and the mitochondrial apoptosis pathway, which may be a valuable candidate for the treatment of IVD degeneration.