[Evaluation of Energy Saving and Carbon Reduction Effect of Air Pollution Prevention and Control Action Plan and Innovation Intermediary Effect].

In order to evaluate the effect and mechanism of energy saving and carbon reduction of the Air Pollution Prevention and Control Action Plan (the Policy), on the basis of measuring the energy consumption and CO2 emissions of GDP per unit area in 281 prefecture-level cities and above from 2003 to 2017, the influence, intermediary effect of innovation, and urban heterogeneity of the Policy on energy saving and carbon reduction were explored by using a difference-in-difference model. The results showed that:① the Policy promoted a significant reduction of 17.60% in the energy consumption intensity and 19.99% in the carbon emission intensity in the whole sample city. Based on a series of robustness tests, such as the parallel trend test, overcomed endogenous and placebo, dynamic time window and counterfactual, difference-in-difference-in-differences, and PSM-DID estimation, the above conclusions were still valid. ② Mechanism analysis showed that the Policy achieved energy saving and carbon reduction through the direct innovation intermediary effect of green invention patents as the carrier, and the indirect innovation mediation effect of the industrial structure upgrading effect caused by innovation achieved an energy-saving effect. ③ Heterogeneity analysis showed that the energy saving and carbon reduction rate of the Policy for coal-consuming provinces was 0.86% and 3.25% higher than that of non-coal-consuming provinces. The carbon reduction in the old industrial base city was 36.43% higher than that in the non-old industrial base, but the energy saving effect was 8.93% lower than that of the non-old industrial base. The range of energy saving and carbon reduction in non-resource-based cities was 31.30% and 74.95% higher than that in resource-based cities, respectively. ④ The results showed that it was necessary to strengthen the innovation investment and industrial structure upgrading in key areas such as big coal-consumption provinces, old industrial base cities, and resource-based cities, so as to give full play to the energy saving and carbon reduction effect of the Policy.

Application of metagenomic next-generation sequencing in patients with infective endocarditis.

Objectives: Metagenomic next-generation sequencing (mNGS) technology is helpful for the early diagnosis of infective endocarditis, especially culture-negative infective endocarditis, which may guide clinical treatment. The purpose of this study was to compare the presence of culture-negative infective endocarditis pathogens versus culture-positive ones, and whether mNGS test results could influence treatment regimens for patients with routine culture-negative infective endocarditis. Methods: The present study enrolled patients diagnosed with infective endocarditis and tested for mNGS in the First Affiliated Hospital of Zhengzhou University from February 2019 to February 2022 continuously. According to the culture results, patients were divided into culture-negative group (Group CN, n=18) and culture-positive group (Group CP, n=32). The baseline characteristics, clinical data, pathogens, 30 day mortality and treatment regimen of 50 patients with infective endocarditis were recorded and analyzed. Results: Except for higher levels of PCT in the Group CN [0.33 (0.16-2.74) ng/ml vs. 0.23 (0.12-0.49) ng/ml, P=0.042], there were no significant differences in the basic clinical data and laboratory examinations between the two groups (all P>0.05). The aortic valve and mitral valve were the most involved valves in patients with infective endocarditis (aortic valve involved: Group CN 10, Group CP 16; mitral valve involved: Group CN 8, Group CP 21; P>0.05) while 9 patients had multiple valves involved (Group CN 2, Group CP 7; P>0.05). The detection rate of non-streptococci infections in the Group CN was significantly higher than that in the Group CP (9/18 vs. 3/32, P=0.004). There was no significant difference in patients with heart failure hospitalization and all-cause death at 30 days after discharge (3 in Group CN vs. 4 in Group CP, P>0.05). It is worth noting that 10 patients with culture-negative infective endocarditis had their antibiotic regimen optimized after the blood mNGS. Conclusions: Culture-negative infective endocarditis should be tested for mNGS for early diagnosis and to guide clinical antibiotic regimen.

Comprehensive assessment of osteoporosis in lumbar spine using compositional MR imaging of trabecular bone.

OBJECTIVES: To comprehensively assess osteoporosis in the lumbar spine, a compositional MR imaging technique is proposed to quantify proton fractions for all the water components as well as fat in lumbar vertebrae measured by a combination of a 3D short repetition time adiabatic inversion recovery prepared ultrashort echo time (STAIR-UTE) MRI and IDEAL-IQ. METHODS: A total of 182 participants underwent MRI, quantitative CT, and DXA. Lumbar collagen-bound water proton fraction (CBWPF), free water proton fraction (FWPF), total water proton fraction (TWPF), bone mineral density (BMD), and T-score were calculated in three vertebrae (L2-L4) for each subject. The correlations of the CBWPF, FWPF, and TWPF with BMD and T-score were investigated respectively. A comprehensive diagnostic model combining all the water components and clinical characteristics was established. The performances of all the water components and the comprehensive diagnostic model to discriminate between normal, osteopenia, and osteoporosis cohorts were also evaluated using receiver operator characteristic (ROC). RESULTS: The CBWPF showed strong correlations with BMD (r = 0.85, p < 0.001) and T-score (r = 0.72, p < 0.001), while the FWPF and TWPF showed moderate correlations with BMD (r = 0.65 and 0.68, p < 0.001) and T-score (r = 0.47 and 0.49, p < 0.001). The high area under the curve values obtained from ROC analysis demonstrated that CBWPF, FWPF, and TWPF have the potential to differentiate the normal, osteopenia, and osteoporosis cohorts. At the same time, the comprehensive diagnostic model shows the best performance. CONCLUSIONS: The compositional MRI technique, which quantifies CBWPF, FWPF, and TWPF in trabecular bone, is promising in the assessment of bone quality. KEY POINTS: • Compositional MR imaging technique is able to quantify proton fractions for all the water components (i.e., collagen-bound water proton fraction (CBWPF), free water proton fraction (FWPF), and total water proton fraction (TWPF)) in the human lumbar spine. • The biomarkers derived from the compositional MR imaging technique showed moderate to high correlations with bone mineral density (BMD) and T-score and showed good performance in distinguishing people with different bone mass. • The comprehensive diagnostic model incorporating CBWPF, FWPF, TWPF, and clinical characteristics showed the highest clinical diagnostic capability for the assessment of osteoporosis.

Analysis of influencing factors for prognosis of patients with ventricular septal perforation: A single-center retrospective study.

Background: Ventricular septal rupture (VSR) is a type of cardiac rupture, usually complicated by acute myocardial infarction (AMI), with a high mortality rate and often poor prognosis. The aim of our study was to investigate the factors influencing the long-term prognosis of patients with VSR from different aspects, comparing the evaluation performance of the Gensini score, Sequential Organ Failure Assessment (SOFA) score and European Heart Surgery Risk Assessment System II (EuroSCORE II) score systems. Methods: This study retrospectively enrolled 188 patients with VSR between Dec 9, 2011 and Nov 21, 2021at the First Affiliated Hospital of Zhengzhou University. All patients were followed up until Jan 27, 2022 for clinical data, angiographic characteristics, echocardiogram outcomes, intraoperative, postoperative characteristics and major adverse cardiac events (MACEs) (30-day mortality, cardiac readmission). Cox proportional hazard regression analysis was used to explore the predictors of long-term mortality. Results: The median age of 188 VSR patients was 66.2 ± 9.1 years and 97 (51.6%) were males, and there were 103 (54.8%) patients in the medication group, 34 (18.1%) patients in the percutaneous transcatheter closure (TCC) group, and 51 (27.1%) patients in the surgical repair group. The average follow-up time was 857.4 days. The long-term mortality of the medically managed group, the percutaneous TCC group, and the surgical repair group was 94.2, 32.4, and 35.3%, respectively. Whether combined with cardiogenic shock (OR 0.023, 95% CI 0.001-0.054, P = 0.019), NT-pro BNP level (OR 0.027, 95% CI 0.002-0.34, P = 0.005), EuroSCORE II (OR 0.530, 95% CI 0.305-0.918, P = 0.024) and therapy group (OR 3.518, 95% CI 1.079-11.463, P = 0.037) were independently associated with long-term mortality in patients with VSR, and this seems to be independent of the therapy group. The mortality rate of surgical repair after 2 weeks of VSR was much lower than within 2 weeks (P = 0.025). The cut-off point of EuroSCORE II was determined to be 14, and there were statistically significant differences between the EuroSCORE II < 14 group and EuroSCORE II≥14 group (HR = 0.2596, 95%CI: 0.1800-0.3744, Logrank P < 0.001). Conclusion: Patients with AMI combined with VSR have a poor prognosis if not treated surgically, surgical repair after 2 weeks of VSR is a better time. In addition, EuroSCORE II can be used as a scoring system to assess the prognosis of patients with VSR.

Automated Magnetic Resonance Image Segmentation of Spinal Structures at the L4-5 Level with Deep Learning: 3D Reconstruction of Lumbar Intervertebral Foramen.

OBJECTIVE: 3D reconstruction of lumbar intervertebral foramen (LIVF) has been beneficial in evaluating surgical trajectory. Still, the current methods of reconstructing the 3D LIVF model are mainly based on manual segmentation, which is laborious and time-consuming. This study aims to explore the feasibility of automatically segmenting lumbar spinal structures and increasing the speed and accuracy of 3D lumbar intervertebral foramen (LIVF) reconstruction on magnetic resonance image (MRI) at the L4-5 level. METHODS: A total of 100 participants (mean age: 42.2 ± 14.0 years; 52 males and 48 females; mean body mass index, 22.7 ± 3.2 kg/m2 ), were enrolled in this prospective study between March and July 2020. All participants were scanned on L4-5 level with a 3T MR unit using 3D T2-weighted sampling perfection with application-optimized contrast with various flip-angle evolutions (SPACE) sequences. The lumbar spine's vertebra bone structures (VBS) and intervertebral discs (IVD) were manually segmented by skilled surgeons according to their anatomical outlines from MRI. Then all manual segmentation were saved and used for training. An automated segmentation method based on a 3D U-shaped architecture network (3D-UNet) was introduced for the automated segmentation of lumbar spinal structures. A number of quantitative metrics, including dice similarity coefficient (DSC), precision, and recall, were used to evaluate the performance of the automated segmentation method on MRI. Wilcoxon signed-rank test was applied to compare morphometric parameters, including foraminal area, height and width of 3D LIVF models between automatic and manual segmentation. The intra-class correlation coefficient was used to assess the test-retest reliability and inter-observer reliability of multiple measurements for these morphometric parameters of 3D LIVF models. RESULTS: The automatic segmentation performance of all spinal structures (VBS and IVD) was found to be 0.918 (healthy levels: 0.922; unhealthy levels: 0.916) for the mean DSC, 0.922 (healthy levels: 0.927; unhealthy levels: 0.920) for the mean precision, and 0.917 (healthy levels: 0.918; unhealthy levels: 0.917) for the mean recall in the test dataset. It took approximately 2.5 s to achieve each automated segmentation, far less than the 240 min for manual segmentation. Furthermore, no significant differences were observed in the foraminal area, height and width of the 3D LIVF models between manual and automatic segmentation images (P > 0.05). CONCLUSION: A method of automated MRI segmentation based on deep learning algorithms was capable of rapidly generating accurate segmentation of spinal structures and can be used to construct 3D LIVF models from MRI at the L4-5 level.

Automatic Grading of Disc Herniation, Central Canal Stenosis and Nerve Roots Compression in Lumbar Magnetic Resonance Image Diagnosis.

Aim: Accurate severity grading of lumbar spine disease by magnetic resonance images (MRIs) plays an important role in selecting appropriate treatment for the disease. However, interpreting these complex MRIs is a repetitive and time-consuming workload for clinicians, especially radiologists. Here, we aim to develop a multi-task classification model based on artificial intelligence for automated grading of lumbar disc herniation (LDH), lumbar central canal stenosis (LCCS) and lumbar nerve roots compression (LNRC) at lumbar axial MRIs. Methods: Total 15254 lumbar axial T2W MRIs as the internal dataset obtained from the Fifth Affiliated Hospital of Sun Yat-sen University from January 2015 to May 2019 and 1273 axial T2W MRIs as the external test dataset obtained from the Third Affiliated Hospital of Southern Medical University from June 2016 to December 2017 were analyzed in this retrospective study. Two clinicians annotated and graded all MRIs using the three international classification systems. In agreement, these results served as the reference standard; In disagreement, outcomes were adjudicated by an expert surgeon to establish the reference standard. The internal dataset was randomly split into an internal training set (70%), validation set (15%) and test set (15%). The multi-task classification model based on ResNet-50 consists of a backbone network for feature extraction and three fully-connected (FC) networks for classification and performs the classification tasks of LDH, LCCS, and LNRC at lumbar MRIs. Precision, accuracy, sensitivity, specificity, F1 scores, confusion matrices, receiver-operating characteristics and interrater agreement (Gwet k) were utilized to assess the model's performance on the internal test dataset and external test datasets. Results: A total of 1115 patients, including 1015 patients from the internal dataset and 100 patients from the external test dataset [mean age, 49 years ± 15 (standard deviation); 543 women], were evaluated in this study. The overall accuracies of grading for LDH, LCCS and LNRC were 84.17% (74.16%), 86.99% (79.65%) and 81.21% (74.16%) respectively on the internal (external) test dataset. Internal and external testing of three spinal diseases showed substantial to the almost perfect agreement (k, 0.67 - 0.85) for the multi-task classification model. Conclusion: The multi-task classification model has achieved promising performance in the automated grading of LDH, LCCS and LNRC at lumbar axial T2W MRIs.

Assessment of Osteoporosis in Lumbar Spine: In Vivo Quantitative MR Imaging of Collagen Bound Water in Trabecular Bone.

AIM: Bone collagen matrix makes a crucial contribution to the mechanical properties of bone by imparting tensile strength and elasticity. The collagen content of bone is accessible via quantification of collagen bound water (CBW) indirectly. We prospectively study the performance of the CBW proton density (CBWPD) measured by a 3D short repetition time adiabatic inversion recovery prepared ultrashort echo time (STAIR-UTE) magnetic resonance imaging (MRI) sequence in the diagnosis of osteoporosis in human lumbar spine. METHODS: A total of 189 participants with a mean age of 56 (ranged from 50 to 86) years old were underwent MRI, quantitative computed tomography (QCT), and dual-energy X-ray absorptiometry (DXA) in lumbar spine. Major fracture risk was also evaluated for all participants using Fracture Risk Assessment Tool (FRAX). Lumbar CBWPD, bone marrow fat fraction (BMFF), bone mineral density (BMD) and T score values were calculated in three vertebrae (L2-L4) for each subject. Both the CBWPD and BMFF were correlated with BMD, T score, and FRAX score for comparison. The abilities of the CBWPD and BMFF to discriminate between three different cohorts, which included normal subjects, patients with osteopenia, and patients with osteoporosis, were also evaluated and compared using receiver operator characteristic (ROC) analysis. RESULTS: The CBWPD showed strong correlation with standard BMD (R2 = 0.75, P < 0.001) and T score (R2 = 0.59, P < 0.001), as well as a moderate correlation with FRAX score (R2 = 0.48, P < 0.001). High area under the curve (AUC) values (≥ 0.84 using QCT as reference; ≥ 0.76 using DXA as reference) obtained from ROC analysis demonstrated that the CBWPD was capable of well differentiating between the three different subject cohorts. Moreover, the CBWPD had better correlations with BMD, T score, and FRAX score than BMFF, and also performed better in cohort discrimination. CONCLUSION: The STAIR-UTE-measured CBWPD is a promising biomarker in the assessment of bone quality and fracture risk.

Detection of Repair of the Zone of Calcified Cartilage with Osteoarthritis through Mesenchymal Stem Cells by Ultrashort Echo Time Magnetic Resonance Imaging.

OBJECTIVE: Currently, magnetic resonance imaging (MRI) is the most commonly used imaging modality for observing the growth and development of mesenchymal stem cells (MSCs) after in vivo transplantation to treat osteoarthritis (OA). However, it is a challenge to accurately monitor the treatment effects of MSCs in the zone of calcified cartilage (ZCC) with OA. This is especially true in the physiological and biochemical views that are not accurately detected by MRI contrast agents. In contrast, ultrashort time echo (UTE) MRI has been shown to be sensitive to the presence of the ZCC, creating the potential for more effectively observing the repair of the ZCC in OA by MSCs. A special focus is given to the outlook of the use of UTE MRI to detect repair of the ZCC with OA through MSCs. The limitations of the current techniques for clinical applications and future directions are also discussed. DATA SOURCES: Using the combined keywords: "osteoarthritis", "mesenchymal stem cells", "calcified cartilage", and "magnetic resonance imaging", the PubMed/MEDLINE literature search was conducted up to June 1, 2017. STUDY SELECTION: A total of 132 published articles were initially identified citations. Of the 132 articles, 48 articles were selected after further detailed review. This study referred to all the important English literature in full. RESULTS: In contrast, UTE MRI has been shown to be sensitive to the presence of the ZCC, creating the potential for more effectively observing the repair of the ZCC in OA by MSCs. CONCLUSIONS: The current studies showed that the ZCC could be described in terms of its histomorphology and biochemistry by UTE MRI. We prospected that UTE MRI has been shown the potential for more effectively observing the repair of the ZCC in OA by MSCs in vivo.

[Magnetic resonance imaging versus DR for whole spine imaging in patients with degenerative spinal disease].

OBJECTIVE: To assess the quality of whole spine images obtained by DR and magnetic resonance imaging (MRI) and analyze the whole spinal imaging sagittal parameters for standing DR and supine MRI. METHODS: Sixty-one patients aged 49.9∓17.6 years with degenerative spinal disease underwent both standing DR and supine MRI of the whole spine from November, 2010 to March, 2016. The image quality was retrospectively reviewed, and the cervical lordosis (CL), thoracic kyphosis (TK), lumbar lordosis (LL), sacral slope (SS), and sagittal vertical axis (SVA) were measured on the whole spinal lateral DR and middle sagittal MR images. RESULTS: Both the DR and MR whole spine images had a high quality (100%). The CL, TK, LL, SS, and SVA measured were 28.37mnplus;10.91 °, 29.98mnplus;8.96 °, 45.61mnplus;12.46 °, 34.38mnplus;9.05 °, and 17.20mnplus;26.39 mm on DR images and were 24.34mnplus;9.01 °, 21.22mnplus;8.13 °, 41.45mnplus;12.17 °, 37.45mnplus;8.19 °, and 36.51mnplus;12.44mm on MR images, respectively, showing significant differences in the measurements between the two modalities (P=0.000, 0.000, 0.000, 0.001, and 0.007, respectively). The correlation coefficient between DR and MR images for CL, TK, LL, SS, and SVA were 0.69, 0.68, 0.72, 0.51, and 0.27 (P=0.000, 0.000, 0.000, 0.000, and 0.034, respectively). CONCLUSION: Both standing DR and supine MR whole spine imaging can provide high-quality images. The CL, TK, LL, SS, and SVA measured on supine MR whole spine images are correlated with those on standing DR images but differ obviously. Supine MR imaging can not substitute standing DR examinations, and comprehensive assessment of degenerative spinal disease needs the combination of the two imaging techniques.

[Effect of superparamagnetic iron oxide on differentiation of rat bone marrow stem cells into chondrocytes in vitro].

OBJECTIVE: To observe the effect of superparamagnetic iron oxide (SPIO) on the differentiation of rat bone marrow stem cells (BMSCs) into chondrocytes in vitro and explore the possible mechanism. METHODS: CCK8 assay was performed to examine the cytotoxicity of SPIO (1 and 5 µg/mL) on cultured SD rat BMSCs. Prussian blue staining and fluorescence excitation assay were used to assess the binding of the SPIO to BMSCs after the cells had been cultured in chondrocytes-induced medium in the presence of SPIO (1 and 5 µg/mL) for 9 days. The mRNA levels of COL2 α2, aggrecan and MMP13 in the cell culture were examined using Q-PCR, and the chondrogenic differentiation of the BMSCs was analyzed using alcian blue staining and immunofluorescence staining for COL2 α2. The protein levels of COL2 α2, aggrecan, MMP13, Ihh and PTHrP in the cells were examined using Western blotting. RESULTS: CCK8 assay showed no significant toxicity of SPIO on BMSCs. Compared with the control cells, the cells cultured in the presence of SPIO showed increased expressions of COL2 α2 and aggrecan and decreased expression of MMP13 at both mRNA and protein levels with also significantly increased expressions of Ihh and PTHrP proteins. CONCLUSION: SPIO can promote the differentiation of rat BMSCs into chondrocytes and up-regulate the Ihh/PTHrP signal pathway, suggesting the potential of SPIO as a new therapeutic agent for chondrocyte-related diseases.

Role of Diffusion-weighted and Contrast-enhanced Magnetic Resonance Imaging in Differentiating Activity of Ankylosing Spondylitis.

BACKGROUND: Previous studies showed that combining apparent diffusion coefficient (ADC) value with the Spondyloarthritis Research Consortium of Canada (SPARCC) index value might provide a reliable evaluation of the activity of ankylosing spondylitis (AS), and that contrast-enhanced (CE) magnetic resonance imaging (MRI) is unnecessary. However, the results were based on confirming only a small random sample. This study aimed to assess the role of CE-MRI in differentiating the disease activity of AS by comparing ADC value with a large sample. METHODS: A total of 115 patients with AS were enrolled in accordance with Bath AS Disease Activity Index and laboratory indices, and 115 patients were divided into two groups, including active group (n = 69) and inactive group (n = 46). SPARCC, ΔSI, and ADC values were obtained from the short tau inversion recovery (STIR), diffusion-weighted imaging (DWI), and CE-MRI, respectively. One-way analysis of variance and receiver operating characteristic analysis were performed for all parameters. RESULTS: The optimal cutoff values (with sensitivity, specificity, respective area under the curve, positive likelihood ratio, and negative likelihood ratio) for the differentiation between active and inactive groups are as follows: SPARCC = 6 (72.06%, 82.61%, 0.836, 4.14, 0.34); ΔSI (%) = 153 (80.6%, 84.78%, 0.819, 5.3, 0.23); ADC value = 1.15 × 10-3 mm2/s (72.73%, 81.82%, 0.786, 4, 0.33). No statistical differences were found among the predictive values of SPARCC, ΔSI, and ADC. Multivariate analysis showed no significant difference between the combination of SPARCC and ADC values with and without ΔSI. CONCLUSIONS: Using large sample, we concluded that the combination of STIR and DWI would play significant roles in assessing the disease activity, and CE-MRI sequence is not routinely used in imaging of AS to avoid renal fibrosis and aggravation of kidney disease.

2-Methoxyestradiol inhibits the proliferation and migration and reduces the radioresistance of nasopharyngeal carcinoma CNE-2 stem cells via NF-κB/HIF-1 signaling pathway inactivation and EMT reversal.

Accumulating evidence indicates that cancer stem cells (CSCs) are a source of resistance to radiation therapy (RT); however, the mechanism of this resistance remains unclear. 2-Methoxyestradiol (2-ME2) is a metabolic product of estrogen in the body. Recent studies have found that 2-ME2 regulates the activation of transcription factors, including nuclear factor (NF)-κB/hypoxia-inducible factor-1 (HIF-1), thus contributing to tumor cell apoptosis and chemosensitivity. Therefore, 2-ME2 is being studied as a potential anticancer drug. The purpose of this study was to determine the effect and mechanism by which 2-ME2 inhibits nasopharyngeal carcinoma CNE-2 stem-like cell (NPCSC) proliferation and migration and reduces NPCSC radioresistance. This study has important significance for reducing the radioresistance of these cells to improve the cure rate of NPC. First, the NPCSCs were collected in a serum-free culture system and then identified by relevant experiments. The NPCSCs were treated with 2-ME2 (0-8 µM) combined with X-ray exposure and Cell Counting Kit-8 (CCK-8), Transwell assay, colony formation assay, western blot analysis, RT-PCR, flow cytometry and RNA interference technology were used to explore the effect and mechanism of 2-ME2 on NPCSCs. The results showed that the microspheres collected in the serum­free culture system possessed CSC traits and radioresistance. 2-ME2 obviously inhibited NPCSC growth and migration and reduced NPCSC radioresistance. 2-ME2 decreased NF-κB p65 and HIF-1α protein expression, downregulated NF-κB p65 nuclear localization, and reversed epithelial-mesenchymal transition (EMT). NF-κB p65 knockdown reduced HIF-1α expression, reversed EMT, and enhanced the suppressive effect of 2-ME2 on NPCSCs. Collectively, these data indicate that 2-ME2 inhibits NPCSC proliferation and migration and reduces the radioresistance of NPCSCs via NF-κB/HIF-1 signaling pathway inactivation and EMT reversal.

[Correlation between vertebral bone marrow fat and abdomen fat: a prospective study].

OBJECTIVE: To investigate the correlation between the lumbar bone marrow fat and abdominal fat. METHODS: A total of 68 individuals (32 men and 36 women, aged 21-74 years with a median of 49.5 years) were included in this study. All the subjects underwent spectroscopic examination of the third lumber vertebra with the single voxel method on a 1.5T MR scanner to measure the fat fraction (FF%). Quantitative CT was also performed for measurement of the abdomen subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT). The measurements were compared between subjects aged ≥50 years and those below 50 years, respectively,in male or female subjects. RESULTS: In male subjects, BMI, FF%, VAT or SAT showed no significant differences between the two age groups (P>0.05), and FF% was not correlated with BMI, VAT or SAT (r=0.109, 0.034, 0.066, respectively; P>0.05). In the female subjects, BMI, FF%, VAT and SAT differed significantly between the two age groups (P<0.05), and in ≥50 years group, FF% showed a positive correlation with VAT (r=0.499, P<0.05) but was not correlated with SAT (r=0.221, P>0.05); in<50 years group, FF% was not correlated with VAT or SAT (r=0.076, -0.067, respectively; P>0.05). CONCLUSION: FF% is positively correlated with VAT in female subjects aged beyond 50 years, but is not correlated with VAT or SAT in male subjects or in younger female subjects.

[Magnetic Resonance Imaging Tracing the Biodistribution of SPIO-shRNA Molecular Probe in vivo].

OBJECTIVES: To investigate the biodistribution of superparamagnetic iron oxide (SPIO)-shRNA molecular probe by magnetic resonance imaging (MRI) in vivo. METHODS: Six New Zealand white rabbits were injected intravenously with SPIO-shRNA molecular probe (9.6 mg Fe/kg) via ear edge vein. The blood samples were collected to analyse the pharmacokinetic parameters through measuring the iron content by atomic absorption spectrometry (AAS) method at 30 min before and 1 min, 3 min, 5 min, 10 min, 15 min, 30 min and at 1, 2, 3, 6, 12, and 24 h after the injection. Six Kun Ming (KM) mice were injected intravenously with SPIO-shRNA molecular probe (4.8 mg Fe/kg). The biodistribution of SPIO-shRNA molecular probe was traced by MRI in vivo. Ninety six KM mice were randomly divided into control group and experimental group: each mouse in experimental group was injected intravenously with SPIO-shRNA molecular probe (4.8 mg Fe/kg). The liver, spleen, kidney, brain and muscle of the control group and the experimental group on 1, 3, 5, 7, 9, 11 and 14 d after the injection were collected. The organ iron content were measured by AAS method and Prussian blue staining in order to observe the distribution of the SPIO-shRNA molecular probe in the main organ. RESULTS: Our results demonstrated that the pharmacokinetics of the molecular probe complied with two-compartment model, and the blood half-life was (3.692±0.196) h. The data of MRI showed that the probe were distributed in liver and spleen, and the signs were reduced in accord with the increase of probe's doses in liver and spleen. The probe's metabolism was slow, and the probe was cleared from liver and spleen at 2 weeks after the injection. The results of AAS and Prussian blue staining further testified the results of MRI. CONCLUSIONS: Our data showed the biodistribution of SPIO-shRNA molecular probe in main organs can be traced by MRI in vivo. Meanwhile, it provides important information for the effectiveness of the probe by MRI at tumor in vivo.

[Optimal concentration of superparamagnetic iron oxide-short hairpin RNA dual functional molecular probe transfected into ovarian cancer cells in vitro].

OBJECTIVE: To explore the effects of superparamagnetic iron oxide-short hairpin RNA (SPIO-ShRNA) dual functional molecular probes of different concentrations on morphology and biological behavior of ovarian cancer SKOV3 cells in vitro. METHODS: The dual functional molecular probes at an iron concentration of 5, 15, 30, 45, 75, and 100 mg/L were transfected into SKOV3 cells. The transfection rate of the probe was observed by fluorescence microscope. The distribution and content of iron particles in SKOV3 cells were determined by Prussian blue staining, atomic adsorption spectrometer and electron microscopy. Cell viability was observed by cell counting kit-8 (CCK-8).The apoptosis was detected by flow cytometry. The expression of protein within the cells was detected by Western blot. The changes of the signal intensity were measured by magnetic resonance imaging (MRI). RESULTS: The SPIO-ShRNA dual functional molecular probe was uptaken in aconcentration-dependence manner within a certain range (5-30 mg/L). When the concentration of the probe was 45 mg/L, the labeling rate of the cell was close to 100%; With the increase of the concentration of probe, the cell survival rate decreased gradually. The cell survival rate of each experimental group were 94.626%±1.050%, 93.373%±1.180%, 91.700%±3.122%, 75.100%±4.362%, 72.983%±3.233%, 71.010%±2.910%,5, 15, 30 mg/L cell survival rate was not significantly decreased, the difference was not statistically significant (P=0.226, P=0.068, P=0.475); When the concentration of the probe was greater than or equal to 45 mg/L,the survival rate decreased obviously (P<0.001); Group of 45 mg/L protein expression rate was 68.905%±3.510%, When the concentration of the probe was greater than or equal to 45 mg/L, the inhibition rate of the protein expression level of epidermal growth factor receptor was obviously higher than those of 5, 15, and 30 mg/L groups, the difference was statistically significant (P<0.001, P=0.001, P=0.003, all P<0.01); the MRI displayed that the signal intensity was decreased with increasing concentrations of the probe. The signal intensity of 45 mg/L group was 165.55±4.92, compared with the blank control group(same volume of phosphate buffer saline), normal group (unlabeled ovarian cancer SKOV3 cells), 5, 15, and 30 mg/L groups , the signal intensity of 45 mg/L group decreased significantly (all P<0.001). CONCLUSION: The dual functional molecular probe can effectively transfect and specifically inhibit the expression of SKOV3 cell lines at the iron concentration of 45 mg/L, and can also be detected by MRI. The role of diagnosis and treatment of the dual functional molecular probe has been initially confirmed.

Intravenous Injections of Human Mesenchymal Stromal Cells Modulated the Redox State in a Rat Model of Radiation Myelopathy.

The main aim of the present study was to assess the antioxidative effects of human umbilical cord-derived mesenchymal stromal cells (UC-MSCs) in a rat model of radiation myelopathy. UC-MSCs were isolated from Wharton's jelly (WJ) of umbilical cords. An irradiated cervical spinal cord rat model (C2-T2 segment) was generated using a (60)Co irradiator to deliver 30 Gy of radiation. UC-MSCs were injected through the tail vein at 90 days, 97 days, 104 days, and 111 days after-irradiation. Histological damage was examined by cresyl violet/Nissl staining. The activities of two antioxidant enzymes catalase (CAT) and glutathione peroxidase (GPX) in the spinal cord were measured by the biomedical assay. In addition, the levels of vascular endothelial growth factor (VEGF) and angiopoietin-2 (Ang-2) in the spinal cord were determined by ELISA methods. Multiple injections of UC-MSCs through the tail vein ameliorated neuronal damage in the spinal cord, increased the activities of the antioxidant enzymes CAT and GPX, and increased the levels of VEGF and Ang-2 in the spinal cord. Our results suggest that multiple injections of UC-MSCs via the tail vein in the rat model of radiation myelopathy could significantly improve the antioxidative microenvironment in vivo.

Bergapten promotes bone marrow stromal cell differentiation into osteoblasts in vitro and in vivo.

Many recent studies have suggested that bergapten (BP), a class of native compound with numerous biological activities such as anti-resorptive properties, may exert protective effects against postmenopausal bone loss. However, it remains unknown whether BP regulates or improves the osteogenic function of bone marrow stromal cells (BMSCs) in the treatment and prevention of osteoporosis. In our study, BMSCs were cultured in osteogenic induction medium with the addition of BP for 2 weeks and an ovariectomized mouse model of osteoporosis was used to investigate the anti-resorptive effect of BP by gavage administration for 3 months. The concentrations of BP used were 0.1, 1, and 10 µmol/L in vitro and the gavage dose was 20 mg/kg/d. The result of our study indicated that BP promotes the expression of alkaline phosphatase (ALP) by BMSCs in vitro in a dose-dependent manner, as revealed by ALP staining. Runt-related transcription factor 2 and osteocalcin were up-regulated both in vitro and vivo, while osterix and collagen Iα1, assessed by immunofluorescence and immunohistochemistry, were correspondingly raised in the presence of BP in BMSCs in vitro. In addition, a protective effect of BP against ovariectomy-induced bone loss was found by distal femur micro-CT scanning, with improvements of bone metabolism parameters such as bone mineral density, trabecular number, and trabecular separation. Furthermore, WNT/ß-catenin signaling was activated in the presence of BP in BMSCs in osteogenic culture. Finally, BP promoted differentiation of BMSCs into osteoblasts by up-regulation of the WNT/ß-catenin pathway.

Detection of Active Sacroiliitis with Ankylosing Spondylitis through Intravoxel Incoherent Motion Diffusion-Weighted MR Imaging.

OBJECTIVE: To confirm feasibility and assess intravoxel incoherent motion (IVIM) to differentiate active sacroiliitis and ankylosing spondylitis.. METHODS: Forty-one patients were divided into two groups, an active group (n = 20) and a chronic group (n = 21), according to the Bath Ankylosing Spondylitis (AS) Disease Activity Index (BASDAI) and laboratory parameters. In addition, 21 healthy volunteers were chosen as the control group. Tissue diffusivity (Dslow), perfusion fraction (f), and pseudo-diffusion coefficient (Dfast) values were obtained for all three groups. One-way analysis of variance and receiver operating characteristic analysis were performed for all parameters. RESULTS: There was good interobserver agreement on the measurements between the two observers. The optimal cut-off values (with respective AUC, sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio) between active and chronic groups were Dslow = 0.53 × 10(-3) mm(2)/s (0.976, 90%, 95.2%, 18.9, 0.10) and f = 0.09 (0.545, 20%, 95.5%, 4.2, 0.84), and between chronic and control groups were Dslow = 0.22 × 10(-3) mm(2)/s (0.517, 9.52%, 100%, no number, 0.9) and f = 0.09 (0.935, 95.24%, 80.95%, 5, 0.059). CONCLUSION: Dslow and f of IVIM diffusion-weighted (DW)-MRI in AS show a significant difference in the values of diffusion of water molecules and fractional perfusion-related volume among the three groups. KEY POINTS: • D slow can be used to differentiate the activity of AS. • With perfusion fraction, the sensitivity of differentiating the AS activity is improved. • IVIM DWI plays an important role in detecting the activity in patients with AS.

Effects of external magnetic field on the transfection rate of SPIO-shRNADual functional molecular probe into ovarian carcinoma SKOV3 cells in vitro.

OBJECTIVE: To explore the transfection rate of SPIO-shRNA dual functional molecular probe into ovarian carcinoma SKOV3 cells in external magnetic field. METHODS: Dual functional molecular probe at an iron concentration of 45 mg/L was transfected into SKOV3 cells. The cells with coexisting probe and magnetic fields were set as the intervention group,the probe-transfected cells as negative control group, and normally cultured SKOV3 without any transfection as blank control group. The transfection rate was detected by flow cytometry. Cell viability was observed by CCK-8 assay. Epidermal growth factor receptor (EGFR) expression level in SKOV3 cells was determined by real-time quantitative PCR and Western blot analysis. The signal intensity was measured by magnetic resonance imaging (MRI). RESULTS: The transfection rate of the intervention group was (79.20 ± 3.31)%, which was significantly higher than that of negative control group (P=0.001). Compared with the negative control group,the cell viability of the intervention group significantly decreased (P=0.011), protein and mRNA expression levels of EGFR in the intervention group were significantly decreased (both P<0.05). The signal intensity on T2(*)WI in the intervention group also significantly decreased (P=0.0004). CONCLUSION: The external magnetic field can improve the transfection efficiency SPIO-shRNA dual functional molecular probe into ovarian carcinoma SKOV3 cells.

(-)-Epigallocatechin-3-gallate inhibits nasopharyngeal cancer stem cell self-renewal and migration and reverses the epithelial-mesenchymal transition via NF-κB p65 inactivation.

The cancer stem cell (CSC) theory states that many types of cancer, including nasopharyngeal cancer (NPC), are initiated from and maintained by CSCs, which may be responsible for tumor relapse and resistance to therapy. It is imperative that nasopharyngeal cancer stem cells (NPCSCs) be specifically targeted to eradicate NPC and prevent recurrence. Epigallocatechin-3-gallate (EGCG) inhibits cancer progression by attenuating NF-κB p65 activity, which is upregulated in CSCs and plays an important role in epithelial-mesenchymal transition (EMT). The purpose of this study is to confirm the self-renewal and migration inhibitory effects of EGCG toward NPCSCs and to clarify its mechanism of activity. We enriched and characterized NPCSCs by collecting spheroid-derived cells grown in serum-free medium (SFM) and examined the effects of EGCG on the characteristics of NPCSCs and studied the underlying mechanisms using soft agar colony assays, transwell migration assays, reverse transcriptase polymerase chain reaction (RT-PCR), Western blot analysis, immunofluorescence staining, and xenograft studies. NPC spheroids enriched from NPC cell lines acquired CSC traits and underwent EMT. EGCG inhibited the NPCSCs' self-renewal and migration and reversed EMT, and combined treatment with EGCG and cisplatin reduced the growth of CSC tumor xenografts. Moreover, EGCG inhibited NF-κB p65 activity by modulating the cellular localization of p65 and decreasing the transcriptional regulation of NF-κB p65 on Twist1 expression. NF-κB p65 is a novel therapeutic target in NPCSCs, and the inhibition of activated NF-κB p65 in CSCs by EGCG may offer an effective treatment for NPC.