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1.
PLoS One ; 19(3): e0298378, 2024.
Article in English | MEDLINE | ID: mdl-38427661

ABSTRACT

The Chinese government's environmental conservation efforts require the active participation of all society. This study investigated how internal and external efficacy influence pro-environmental behavior with environmental willingness as a mediator. This study employed a structural equation model to analyze the data from 1499 survey questionnaires. The analysis revealed that both internal and external efficacy can enhance individuals' pro-environmental behavior in the private and public spheres. External efficacy has a stronger impact on environmental willingness and public sphere environmental behavior, while internal efficacy more significantly influences private sphere environmental behavior. Additionally, environmental willingness only mediates efficacy and public sphere environmental behavior. The innovation of this study is the examination of internal and external efficacy from the perspective of different sources and the comparison of their differential impacts on pro-environmental behavior. Relevant policies should effectively enhance residents' internal and external efficacy to comprehensively improve their level of pro-environmental behavior.


Subject(s)
Behavior Therapy , Policy , Humans , Surveys and Questionnaires
2.
Neurochem Res ; 49(4): 815-833, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38170383

ABSTRACT

Ischemic stroke is a common neurological disease. Currently, there are no Food and Drug Administration-approved drugs that can maximize the improvement in ischemic stroke-induced nerve damage. Hence, treating ischemic stroke remains a clinical challenge. Ferroptosis has been increasingly studied in recent years, and it is closely related to the pathophysiological process of ischemic stroke. Iron overload, reactive oxygen species accumulation, lipid peroxidation, and glutamate accumulation associated with ferroptosis are all present in ischemic stroke. This article focuses on describing the relationship between ferroptosis and ischemic stroke and summarizes the relevant substances that ameliorate ischemic stroke-induced neurological damage by inhibiting ferroptosis. Finally, the problems in the treatment of ischemic stroke targeting ferroptosis are discussed, hoping to provide a new direction for its treatment.


Subject(s)
Ferroptosis , Iron Overload , Ischemic Stroke , Humans , Glutamic Acid , Lipid Peroxidation , Reactive Oxygen Species
3.
Am J Chin Med ; 50(1): 313-332, 2022.
Article in English | MEDLINE | ID: mdl-34963428

ABSTRACT

18[Formula: see text]-glycyrrhetinic acid (GA) is the active ingredient of the traditional Chinese medicinal herb Glycyrrhizae radix et rhizoma. We previously demonstrated that GA inhibited tumor growth in hepatocellular carcinoma (HCC). However, the effect of GA on transforming growth factor-[Formula: see text] (TGF-[Formula: see text]-induced epithelial-mesenchymal transition (EMT) and metastasis were still unclear. In this study, in vitro transwell assays and immunofluorescence (IF) demonstrated that GA inhibited TGF-[Formula: see text]-induced migration, invasion and EMT of HCC cells. However, it had little effect on the inhibition of proliferation by TGF-[Formula: see text]. Moreover, we confirmed that GA suppressed the metastasis of HCC cells in vivousing an ectopic lung metastasis model. Furthermore, we found that GA inhibited TGF-[Formula: see text]-induced EMT mainly by reducing the phosphorylation of signal transducer and activator of transcription 3 (STAT3), which played an essential role in TGF-[Formula: see text]-induced EMT and cell mobility. Mechanistically, GA inhibited the phosphorylation of STAT3 by increasing the expression of Src homology 2 domain-containing protein tyrosine phosphatases 1 and 2 (SHP1 and SHP2). Therefore, we concluded that GA inhibited TGF-[Formula: see text]-induced EMT and metastasis via the SHP1&SHP2/STAT3/Snail pathway. Our data provide an attractive therapeutic target for future multimodal management of HCC.


Subject(s)
Carcinoma, Hepatocellular , Glycyrrhetinic Acid , Liver Neoplasms , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/metabolism , Cell Line, Tumor , Cell Movement , Epithelial-Mesenchymal Transition , Glycyrrhetinic Acid/pharmacology , Humans , Liver Neoplasms/pathology , Neoplasm Invasiveness , STAT3 Transcription Factor/metabolism , Transforming Growth Factor beta1/genetics , Transforming Growth Factor beta1/metabolism
4.
Bioact Mater ; 6(12): 4729-4757, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34136723

ABSTRACT

Magnesium (Mg) and its alloys, as potential biodegradable materials, have drawn wide attention in the cardiovascular stent field because of their appropriate mechanical properties and biocompatibility. Nevertheless, the occurrence of thrombosis, inflammation, and restenosis of implanted Mg alloy stents caused by their poor corrosion resistance and insufficient endothelialization restrains their anticipated clinical applications. Numerous surface treatment tactics have mainly striven to modify the Mg alloy for inhibiting its degradation rate and enduing it with biological functionality. This review focuses on highlighting and summarizing the latest research progress in functionalized coatings on Mg alloys for cardiovascular stents over the last decade, regarding preparation strategies for metal oxide, metal hydroxide, inorganic nonmetallic, polymer, and their composite coatings; and the performance of these strategies in regulating degradation behavior and biofunction. Potential research direction is also concisely discussed to help guide biological functionalized strategies and inspire further innovations. It is hoped that this review can give assistance to the surface modification of cardiovascular Mg-based stents and promote future advancements in this emerging research field.

5.
Mol Plant ; 14(7): 1149-1167, 2021 07 05.
Article in English | MEDLINE | ID: mdl-33857689

ABSTRACT

The proteolytic degradation of the photodamaged D1 core subunit during the photosystem II (PSII) repair cycle is well understood, but chlorophyll turnover during D1 degradation remains unclear. Here, we report that Arabidopsis thaliana CHLOROPHYLLASE 1 (CLH1) plays important roles in the PSII repair process. The abundance of CLH1 and CLH2 peaks in young leaves and is induced by high-light exposure. Seedlings of clh1 single and clh1-1/2-2 double mutants display increased photoinhibition after long-term high-light exposure, whereas seedlings overexpressing CLH1 have enhanced light tolerance compared with the wild type. CLH1 is localized in the developing chloroplasts of young leaves and associates with the PSII-dismantling complexes RCC1 and RC47, with a preference for the latter upon exposure to high light. Furthermore, degradation of damaged D1 protein is retarded in young clh1-1/2-2 leaves after 18-h high-light exposure but is rescued by the addition of recombinant CLH1 in vitro. Moreover, overexpression of CLH1 in a variegated mutant (var2-2) that lacks thylakoid protease FtsH2, with which CLH1 interacts, suppresses the variegation and restores D1 degradation. A var2-2 clh1-1/2-2 triple mutant shows more severe variegation and seedling death. Taken together, these results establish CLH1 as a long-sought chlorophyll dephytylation enzyme that is involved in PSII repair and functions in long-term adaptation of young leaves to high-light exposure by facilitating FtsH-mediated D1 degradation.


Subject(s)
Arabidopsis Proteins/metabolism , Arabidopsis/enzymology , Carboxylic Ester Hydrolases/metabolism , Heat-Shock Proteins/metabolism , Light , Metalloendopeptidases/metabolism , Photosystem II Protein Complex/metabolism , Plant Leaves/radiation effects , Arabidopsis/growth & development , Arabidopsis/radiation effects , Photosynthesis , Plant Leaves/enzymology , Radiation-Protective Agents , Thylakoids/metabolism
6.
Bioact Mater ; 5(2): 398-409, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32258829

ABSTRACT

Protein exerts a critical influence on the degradation behavior of absorbable magnesium (Mg)-based implants. However, the interaction mechanism between protein and a micro-arc oxidation (MAO) coating on Mg alloys remains unclear. Hereby, a MAO coating was fabricated on AZ31 Mg alloy. And its degradation behavior in phosphate buffer saline (PBS) containing bovine serum albumin (BSA) was investigated and compared with that of the uncoated alloy. Surface morphologies and chemical compositions were studied using Field-emission scanning electron microscope (FE-SEM), Fourier transform infrared spectrophotometer (FT-IR) and X-ray diffraction (XRD). The degradation behavior of the bare Mg alloy and its MAO coating was studied through electrochemical and hydrogen evolution tests. Cytotoxicity assay was applied to evaluate the biocompatibility of Mg alloy substrate and MAO coating. Results indicated that the presence of BSA decreased the degradation rate of Mg alloy substrate because BSA (RCH(NH2)COO‾) molecules combined with Mg2+ ions to form (RCH(NH2)COO)2Mg and thus inhibited the dissolution of Mg(OH)2 by impeding the attack of Cl‾ ions. In the case of MAO coated Mg alloy, the adsorption of BSA on MAO coating and the formation of (RCH(NH2)COO)2Mg exhibited a synergistic effect and enhanced the corrosion resistance of the coated alloy significantly. Furthermore, cell bioactive assay suggested that the MAO coating had good viability for MG63 cells due to its high surface area.

7.
Bioact Mater ; 5(2): 318-333, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32181417

ABSTRACT

The biocorrosion of magnesium in the external physiological environment is still difficult to accurately evaluate the degradation behavior in vivo, particularly, in the microenvironment of the patients with hyperglycemia or diabetes. Thus, we explored the synergistic effects of glucose and protein on the biodegradation of pure magnesium, so as to have a deeper understanding the mechanism of the degradation in vivo. The surface morphology and corrosion product composition of pure magnesium were investigated using SEM, EDS, FTIR, XRD and XPS. The effect of glucose and albumin on the degradation rate of pure magnesium was investigated via electrochemical and immersion tests. The adsorption of glucose and albumin on the sample surface was observed using fluorescence microscopy. The results showed that the presence of 2 g/L glucose changed the micromorphology of corrosion products on the magnesium surface by reacting with metal cations, thus inhibiting the corrosion of pure magnesium. Protein formed a barrier layer to protect the magnesium at early stage of immersion. The chelation reaction between protein and magnesium surface might accelerate the degradation at later stage. There may be a critical glucose (albumin) content. Biodegradation of pure magnesium was inhibited at low concentrations and promoted at high concentrations. The synergistic effect of glucose and protein restrained the adsorption of aggressive chloride ions to a certain extent, and thus inhibited the degradation of pure magnesium considerably. Moreover, XPS results indicated that glucose promoted the adsorption of protein on the sample surface.

8.
Mol Oncol ; 13(4): 792-810, 2019 04.
Article in English | MEDLINE | ID: mdl-30556279

ABSTRACT

Fam134b (JK-1, RETREG1) was first identified as an oncogene in esophageal squamous cell carcinoma. However, the roles of FAM134B during tumorigenesis of hepatocellular carcinoma (HCC) and in epithelial-to-mesenchymal transition (EMT) were previously unclear. In this study, we investigated the function of FAM134B in HCC and the related tumorigenesis mechanisms, as well as how FAM134B induces EMT. We detected the expression of FAM134B in a normal hepatic cell line, HCC cell lines, fresh specimens, and a HCC tissue microarray. A retrospective study of 122 paired HCC tissue microarrays was used to analyze the correlation between FAM134B and clinical features. Gain- and loss-of-function experiments, rescue experiments, Akt pathway activator/inhibitors, nude mice xenograft models, and nude mice lung metastasis models were used to determine the underlying mechanisms of FAM134B in inducing tumorigenesis and EMT in vitro and in vivo. The expression level of FAM134B was highly elevated in HCC, as compared with that in normal liver tissues and normal hepatic cells. Overexpression of FAM134B was significantly associated with tumor size (P = 0.025), pathological vascular invasion (P = 0.026), differentiation grade (P = 0.023), cancer recurrence (P = 0.044), and portal vein tumor thrombus (P = 0.036) in HCC. Patients with high expression of FAM134B had shorter overall survival and disease-free survival than patients with non-high expression of FAM134B. Furthermore, knockdown of FAM134B with shRNAs inhibited cell growth and motility, as well as tumor formation and metastasis in nude mice, all of which were promoted by overexpression of FAM134B. Our study demonstrated that Fam134b is an oncogene that plays a crucial role in HCC via the Akt signaling pathway with subsequent glycogen synthase kinase-3ß phosphorylation, accumulation of ß-catenin, and stabilization of Snail, which promotes tumorigenesis, EMT, and tumor metastasis in HCC.


Subject(s)
Carcinogenesis/pathology , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Epithelial-Mesenchymal Transition , Intracellular Signaling Peptides and Proteins/metabolism , Liver Neoplasms/metabolism , Membrane Proteins/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction , Aged , Animals , Cadherins/metabolism , Carcinogenesis/genetics , Carcinoma, Hepatocellular/genetics , Cell Line, Tumor , Cell Movement , Cell Proliferation , Cyclin D1/metabolism , Enzyme Activation , Female , Gene Expression Regulation, Neoplastic , Glycogen Synthase Kinase 3 beta/metabolism , Humans , Liver Neoplasms/genetics , Liver Neoplasms/pathology , Male , Mice, Inbred BALB C , Mice, Nude , Middle Aged , Neoplasm Metastasis , Protein Stability , Snail Family Transcription Factors/metabolism , Up-Regulation/genetics , beta Catenin/metabolism
9.
Sci Rep ; 8(1): 9365, 2018 06 19.
Article in English | MEDLINE | ID: mdl-29921924

ABSTRACT

18ß-Glycyrrhetinic acid (GA) is the active ingredient of the traditional Chinese medicine, Glycyrrhrzae Radix et Rhizoma. Here, we explored the effects of GA on hepatocellular carcinoma (HCC) in vitro and in vivo and the underlying molecular mechanisms. We confirmed that GA suppressed proliferation of various HCC cell lines. Treatment of GA caused G0/G1 arrest, apoptosis and autophagy in HCC cells. GA-induced apoptosis and autophagy were mainly due to the unfolded protein response. We compared the roles of the ATF4/CHOP and IRE1α/XBP1s UPR pathways, which were both induced by GA. The ATF4/CHOP cascade induced autophagy and was indispensable for the induction of apoptosis in GA-treated HCC cells. In contrast, the IRE1α/XBP1s cascade protected HCC cells from apoptosis in vitro and in vivo induced by GA. Despite this, activation of autophagy protected HCC cells from apoptosis induced by GA. We concluded that pharmacological inhibition of autophagy or IRE1α may be of benefit to enhance the antitumor activity of GA.


Subject(s)
Apoptosis/drug effects , Autophagy/drug effects , Carcinoma, Hepatocellular/metabolism , Glycyrrhetinic Acid/analogs & derivatives , Liver Neoplasms/metabolism , Unfolded Protein Response/genetics , Apoptosis/genetics , Autophagy/genetics , Carcinoma, Hepatocellular/genetics , Cell Cycle/drug effects , Cell Cycle/genetics , Cell Line, Tumor , Cell Survival/drug effects , Cell Survival/genetics , Endoribonucleases/genetics , Endoribonucleases/metabolism , G1 Phase/drug effects , G1 Phase/genetics , Glycyrrhetinic Acid/pharmacology , Hep G2 Cells , Humans , Liver Neoplasms/genetics , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , Resting Phase, Cell Cycle/drug effects , Resting Phase, Cell Cycle/genetics , Unfolded Protein Response/drug effects , X-Box Binding Protein 1/genetics , X-Box Binding Protein 1/metabolism
10.
Sci Rep ; 7(1): 16674, 2017 11 30.
Article in English | MEDLINE | ID: mdl-29192231

ABSTRACT

WRKY transcription factors (TFs) play important roles in stress responses in planta. However, the function of WRKY TFs in the regulation of fruit ripening is unclear. Here, 23 tomato SlWRKYs that are similar to ethylene-responsive WRKY genes from other plant species, or show up-regulation during fruit ripening in previous genome-wide study, were selected, and their function in fruit ripening was investigated. Twelve SlWRKYs were found to be responsive to ethylene (SlER-WRKYs), showing expression patterns similar to those of genes related to fruit ripening. Eight SlER-WRKYs-SlWRKY16, 17, 22, 25, 31, 33, 53, and 54, detected in the nuclei-interacted with and activated the promoters of 4 genes related to color change: Pheophytin Pheophorbide Hydrolase (SlPPH), Pheophorbide a Oxygenase (SlPAO), Phytoene Synthase 1 (SlPSY1) and Phytoene Desaturase (SlPDS). Yeast two-hybrid and bimolecular fluorescence complement (BiFC) assays in Arabidopsis protoplasts indicated that protein interactions occurred between SlWRKY17 and SlRIN, SlERF2b or SlERF7; SlWRKY33 and SlERF7; SlWRKY54 and SlERF2b; and SlWRKY16 and SlWRKY17. Suppression of SlWRKY 16, 17, 53 or 54 by virus-induced gene silencing (VIGS) retarded the red coloration of the fruit. Our study provides comprehensive molecular evidence that WRKY TFs function in fruit ripening, particularly in color change, and are linked to the intricate regulatory network of other ripening regulators.


Subject(s)
Ethylenes/metabolism , Fruit/genetics , Gene Expression Regulation, Plant , Pigmentation/genetics , Solanum lycopersicum/genetics , Transcription Factors/genetics , Gene Expression Profiling , Gene Silencing , Genes, Reporter , Genetic Association Studies , Host-Pathogen Interactions , Solanum lycopersicum/classification , Solanum lycopersicum/growth & development , Solanum lycopersicum/virology , Phenotype , Phylogeny , Promoter Regions, Genetic , Protein Binding , Protein Transport , Transcription Factors/metabolism , Transcriptional Activation , Transcriptome
11.
Plant Physiol ; 169(4): 2391-408, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26514808

ABSTRACT

In contrast to the detailed molecular knowledge available on anthocyanin synthesis, little is known about its catabolism in plants. Litchi (Litchi chinensis) fruit lose their attractive red color soon after harvest. The mechanism leading to quick degradation of anthocyanins in the pericarp is not well understood. An anthocyanin degradation enzyme (ADE) was purified to homogeneity by sequential column chromatography, using partially purified anthocyanins from litchi pericarp as a substrate. The purified ADE, of 116 kD by urea SDS-PAGE, was identified as a laccase (ADE/LAC). The full-length complementary DNA encoding ADE/LAC was obtained, and a polyclonal antibody raised against a deduced peptide of the gene recognized the ADE protein. The anthocyanin degradation function of the gene was confirmed by its transient expression in tobacco (Nicotiana benthamiana) leaves. The highest ADE/LAC transcript abundance was in the pericarp in comparison with other tissues, and was about 1,000-fold higher than the polyphenol oxidase gene in the pericarp. Epicatechin was found to be the favorable substrate for the ADE/LAC. The dependence of anthocyanin degradation by the enzyme on the presence of epicatechin suggests an ADE/LAC epicatechin-coupled oxidation model. This model was supported by a dramatic decrease in epicatechin content in the pericarp parallel to anthocyanin degradation. Immunogold labeling transmission electron microscopy suggested that ADE/LAC is located mainly in the vacuole, with essential phenolic substances. ADE/LAC vacuolar localization, high expression levels in the pericarp, and high epicatechin-dependent anthocyanin degradation support its central role in pigment breakdown during pericarp browning.


Subject(s)
Anthocyanins/metabolism , Catechin/metabolism , Fruit/enzymology , Laccase/metabolism , Litchi/enzymology , Catechol Oxidase/metabolism , Fruit/cytology , Fruit/genetics , Fruit/physiology , Laccase/genetics , Litchi/cytology , Litchi/genetics , Litchi/physiology , Models, Molecular , Oxidation-Reduction , Phenols/metabolism , Phylogeny , Plant Leaves/cytology , Plant Leaves/enzymology , Plant Leaves/genetics , Plant Leaves/physiology , Plant Proteins/genetics , Plant Proteins/metabolism , Nicotiana/genetics , Nicotiana/physiology
12.
PLoS One ; 8(11): e80939, 2013.
Article in English | MEDLINE | ID: mdl-24260516

ABSTRACT

BACKGROUND: Our study aims to evaluate the image quality and feasibility of 128-slice dual-energy CTA (DE-CTA) for supra-aortic arteries using reduced amounts of contrast medium (CM). METHODS: A prospective study was performed in 54 patients receiving CTA of the head and neck with a 128-slice dual-source CT system. Patients were randomized into two groups with a volume of either 40 mL of CM (Group I) or 50 mL of CM (Group II). Arterial and venous enhancements were recorded for quantitative assessment. Qualitative assessments for images without bone removal (BR) were based on a) the visualization of the circle of Willis and b) streak artifacts due to residual CM in the subclavian or internal jugular veins ipsilateral to injection of CM. Qualitative assessment of dual-energy images using BR was based on the presence of bone remnants and vessel integrity. Quantitative data was compared using the Student t test. The χ(2) test was used for the qualitative measurements of streak artifacts in veins while the Mann-Whitney U test was used for the qualitative measurements of images with BR. RESULTS: Arterial and venous attenuation was significantly higher in Group II (P=0.000). Image quality regarding the circle of Willis was excellent in both groups (3.90±0.30 for Group I and 4.00±0 for Group II) . Imaging of the internal jugular veins was scored higher in Group I (1.87±0.72) compared with Group II (1.48±0.51) (P=0.021). Within Group I using BR, mean scores for bone remnants did not differ significantly (P>0.05) but mean scores of vessel integrity (P<0.05) did. CONCLUSIONS: Contrast-enhanced head and neck CTA is feasible using a scan protocol with low amounts of contrast medium (40 mL) on a 128-slice dual-energy CTA. The 40-mL protocol provides satisfactory image quality before and after dual-energy bone-removal post-processing.


Subject(s)
Atherosclerosis/diagnostic imaging , Carotid Arteries/diagnostic imaging , Contrast Media/administration & dosage , Head/diagnostic imaging , Iohexol/analogs & derivatives , Jugular Veins/diagnostic imaging , Neck/diagnostic imaging , Adult , Aged , Angiography, Digital Subtraction/methods , Atherosclerosis/diagnosis , Bone and Bones/diagnostic imaging , Female , Head/blood supply , Humans , Iohexol/administration & dosage , Male , Middle Aged , Neck/blood supply , Prospective Studies , Radiographic Image Interpretation, Computer-Assisted , Tomography, X-Ray Computed/methods
13.
Zhonghua Xin Xue Guan Bing Za Zhi ; 41(5): 411-5, 2013 May.
Article in Chinese | MEDLINE | ID: mdl-24021125

ABSTRACT

OBJECTIVE: To investigate the feasibility of using intravascular loopless monopole antenna (ILMA) to image atherosclerosis plaque in a porcine model with 3.0T magnetic resonance imaging (MRI). METHODS: Atherosclerosis model was established by feeding high fat diet combined with balloon catheter injury to the endothelium in 6 pigs. After 3 months, animals underwent MRI and ILMA examination. The ILMA was invasively inserted to the distal part of abdominal vein and bilateral common iliac veins. MR sequences including T1 weighted imaging (T1WI), T2WI were obtained. MR image data were transferred to post-processing station. Luminal border and external elastic membrane of the vessel were reconstructed based on the MR images. After co-register these images, vessel area, lumen area, vessel wall area and plaque burden in the same lesions imaged by different modality were calculated and compared. Finally, all animals were scarified and hematoxylin eosin (HE) staining was performed in the targeted vessels. Diagnostic accuracy of MR in delineating vessel wall and detecting plaque were analyzed and calculated by comparing with pathological results. RESULTS: The atherosclerotic model was successfully established in all 6 pigs. Good agreement of delineating vessel area, lumen area vessel, wall area and plaque burden were found between MRI and pathology with r value of 0.98, 0.95, and 0.96, respectively (P < 0.001). Compared with pathological findings, the plaque component in corresponding area imaged by MR was as follows: sensitivity and specificity of detecting lipid plaque were 77% and 69%, kappa value was 0.75 ± 0.19 (P < 0.01); sensitivity and specificity on detecting fibrotic plaque were 78% and 73%, Κ value was 0.78 ± 0.18 (P < 0.01). The sensitivity and specificity of detecting calcified plaque were 100%. ILMA results showed that the average lumen area was 49.72 mm(2), average vessel area was 124.08 mm(2), and the average vessel wall area was 74.37 mm(2), ILMA slightly overestimated these indexes as compared with pathological results. CONCLUSION: The results showed that ILMA could be used to image deepened artery and atherosclerotic plaque. Detected plaque size, vessel area, lumen area vessel, wall area, and plaque burden were comparable to pathological findings. It may thus provide an alternative method for detecting atherosclerotic plaque in future research work.


Subject(s)
Magnetic Resonance Angiography/methods , Plaque, Atherosclerotic/diagnosis , Animals , Disease Models, Animal , Swine , Swine, Miniature
14.
Chin Med J (Engl) ; 126(11): 2163-7, 2013.
Article in English | MEDLINE | ID: mdl-23769577

ABSTRACT

BACKGROUND: Noninvasive detection of vulnerable plaque has a significant implication for prevention and treatment of atherosclerotic diseases. The aim of this study is to investigate the difference between vulnerable plaques and stable plaques in magnetic resonance (MR) images. METHODS: Atherosclerosis was induced in twenty male New Zealand white rabbits by high cholesterol diet and balloon injury of the abdominal aorta. After baseline (pre-triggering) MR imaging (MRI) scan, the rabbits underwent pharmaceutical triggering with Russell's viper venom and histamine to induce atherothrombosis, followed by another MRI scan 48 hours later (post-triggering). Rabbits were euthanized to obtain pathological and histological data. The results of MRI were compared with those of pathology and histology. RESULTS: MRI showed that abdominal aorta of the rabbits had pathological change of atherosclerosis in different degrees. Seventy-five plaques were analysed, among which 14 had vulnerable thrombi and 61 stable. Thrombosis was identified in 7 of 11 rabbits by post-triggering MRI, the sensitivity and K value of MR in detection of vulnerable plaque was 71% and 0.803 (P < 0.05). MRI data significantly correlated with the histopathological data in fibrous cap thickness (r = 0.749) plaque area (r = 0.853), lipid core area (r = 0.900). Compared with stable plaques, vulnerable plaques had a significantly thinner fibrous cap ((0.58 ± 0.27) mm vs. (0.95 ± 0.22) mm), larger lipid core area ((7.56 ± 2.78) mm(2) vs. (3.29 ± 1.75) mm(2)), and a higher ratio of lipid core area/plaque area ((55 ± 16)% vs. (27 ± 17)%), but plaque area was comparable in two groups on MRI. The ratio of lipid core area/plaque area was a strong predictor of vulnerable plaques. CONCLUSION: MRI could distinguish vulnerable plaques from stable plaques in a rabbit model of atherothrombosis and may thus be useful as a noninvasive modality for detection of vulnerable plaques in humans.


Subject(s)
Magnetic Resonance Imaging/methods , Plaque, Atherosclerotic/pathology , Animals , Aorta, Abdominal/pathology , Disease Models, Animal , Male , Rabbits , Thrombosis/diagnosis
15.
Chin Med Sci J ; 27(4): 195-200, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23294583

ABSTRACT

Objective To evaluate the image quality (IQ) and radiation dose of 128-slice dual-source computed tomography (DSCT) coronary angiography using prospectively electrocardiogram (ECG)-triggered sequential scan mode compared with ECG-gated spiral scan mode in a population with atrial fibrillation. Methods Thirty-two patients with suspected coronary artery disease and permanent atrial fibrillation referred for a second-generation 128-slice DSCT coronary angiography were included in the prospective study. Of them, 17 patients (sequential group) were randomly selected to use a prospectively ECG-triggered sequential scan, while the other 15 patients (spiral group) used a retrospectively ECG-gated spiral scan. The IQ was assessed by two readers independently, using a four-point grading scale from excel-lent (grade 1) to non-assessable (grade 4), based on the American Heart Association 15-segment model. IQ of each segment and effective dose of each patient were compared between the two groups. Results The mean heart rate (HR) of the sequential group was 96±27 beats per minute (bpm) with a variation range of 73±25 bpm, while the mean HR of the spiral group was 86±22 bpm with a variationrange of 65±24 bpm. Both of the mean HR (t=1.91, P=0.243) and HR variation range (t=0.950, P=0.350) had no significant difference between the two groups. In per-segment analysis, IQ of the sequential group vs. spiral group was rated as excellent (grade 1) in 190/244 (78%) vs. 177/217 (82%) by reader1 and 197/245 (80%) vs. 174/214 (81%) by reader2, as non-assessable (grade 4) in 4/244 (2%) vs. 2/217 (1%) by reader1 and 6/245 (2%) vs. 4/214 (2%) by reader2. Overall averaged IQ per-patient in the sequential and spiral group showed equally good (1.27±0.19 vs. 1.25±0.22, Z=-0.834, P=0.404). The effective radiation dose of the sequential group reduced significantly compared with the spiral group (4.88±1.77 mSv vs. 10.20±3.64 mSv; t=-5.372, P=0.000). Conclusion Compared with retrospectively ECG-gated spiral scan, prospectively ECG-triggered sequential DSCT coronary angiography provides similarly diagnostically valuable images in patients with atrial fibrillation and significantly reduces radiation dose.


Subject(s)
Atrial Fibrillation , Coronary Angiography , Electrocardiography , Humans , Prospective Studies , Radiation Dosage , Tomography, Spiral Computed
16.
Chin Med J (Engl) ; 125(15): 2714-8, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22931980

ABSTRACT

BACKGROUND: With features of high tissue contrast, MRI can be used for the qualitative and quantitative evaluation of atherosclerosis plaques. In this study we investigated the development of atherosclerosis plaque with high resolution 3T MRI in a rabbit model and compared the findings with the histopathological results. METHOD: Twenty male New Zealand white rabbits were randomly allocated into an experimental group (n = 16) and a control group (n = 4). Atherosclerotic lesions were induced in the abdominal aorta by balloon injury and cholesterol feeding. Multiple sequences MRI examination (ToF, T1WI, T2WI, and CE T1WI) were performed at the 2nd, 3rd, and 4th months after aortic denudation. Vessel wall thickness, total vessel area, lumen area, and vessel wall area were recorded. Plaque components were analyzed using histological results as a standard reference. RESULTS: Seventeen rabbits (14 in the experimental group and 3 in the control group) received all three MR examinations. Gradually, from 2 months to 4 months, vessel wall thickness and area in the experimental group increased significantly compared with the control group (P < 0.01). In the lumen area progressive stenosis was not found, even a slight dilation had developed in the experimental group. Lipid, fibrotic and calcified plaques can be differentiated by MR image. According to histological results, MRI had good performance in detection of lipid plaque. CONCLUSION: MRI can be used to monitor progression of atherosclerosis and differentiate plaque components.


Subject(s)
Aorta, Abdominal/pathology , Magnetic Resonance Imaging/methods , Plaque, Atherosclerotic/pathology , Animals , Male , Rabbits , Random Allocation
17.
Zhonghua Yi Xue Za Zhi ; 92(47): 3336-40, 2012 Dec 18.
Article in Chinese | MEDLINE | ID: mdl-23328594

ABSTRACT

OBJECTIVE: To evaluate the incidence, types and clinical significance of coronary artery fistula (CAF) on CT coronary angiography (CTCA). METHODS: A total of 48 533 consecutive patients undergoing CTCA at 4 Chinese hospitals were retrospectively analyzed. The incidence, types and clinical significance of CAF were retrospectively summarized. RESULTS: One hundred and two patients had CAF with the incidence of 0.21% (102/48 533). Among them, coronary to pulmonary artery fistulas were seen in 92 patients (90.2%, 92/102), coronary to right atrium fistula in 4 (3.9%, 4/102), coronary to right ventricular fistula in 2 (2.0%, 2/102), coronary to right ventricular fistula in 2 (2.0%, 2/102), coronary to left atrium fistula in 1 (1.0%, 1/102) and coronary to small cardiac vein in 1 (1.0%, 1/102). Among 92 coronary to pulmonary artery fistulas, fistulas originated from both coronary arteries in 46 patients (50.0%, 46/92), from left coronary artery in 28 (30.4%, 28/92) and right coronary artery in 11 (12.0%, 11/92) and the remaining 7 (7.6%, 7/92) coronary to pulmonary artery fistulas were associated with extracardiac communications. CONCLUSION: The incidence of CAF is 0.21% with a predominance of coronary to pulmonary artery fistulas (90.2%). The most common type of CAF is coronary to pulmonary artery fistulas from both coronary arteries (50.0%). Dual source CTCA can clearly visualize types and abnormal vessels so that it plays an important role in the diagnosis and preoperative evaluation of CAF.


Subject(s)
Arterio-Arterial Fistula/diagnostic imaging , Coronary Artery Disease/diagnostic imaging , Tomography, X-Ray Computed/methods , Adolescent , Adult , Aged , Aged, 80 and over , Arterio-Arterial Fistula/classification , Child , Coronary Angiography , Coronary Artery Disease/classification , Female , Humans , Incidence , Male , Middle Aged , Retrospective Studies , Young Adult
18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(8): 2253-5, 2011 Aug.
Article in Chinese | MEDLINE | ID: mdl-22007427

ABSTRACT

The spatiotemporal distribution of nano-silver in cut gerbera (Gerbera hybrida cv. Crossfire) flowers were determined by inductively coupled plasma-atomic emission spectrometry technique (ICP-AES). The relative standard deviations of this method were between 0.14% and 2.89%, and the recovery ratio obtained by standard addition method ranged from 93.33% to 106.67%. The method was proved to be simple, rapid, reliable and highly sensitive, which can meet the demands of actual sample analysis. The experimental results also showed that Ag could be found in the basal stem end, upper stem end and petal of the cut gerbera flowers treated in nano-silver solution of 5 mg x L(-1) for 24 h and thereafter placed in distilled water. However, the Ag content in basal stem ends was much higher than those in upper stem ends and petals. The results indicated that nano-silver particles could enter into the flower stems through the cuts of stem ends and then moved to different parts of the cut gerbera flowers, but most of them located in the basal stem ends during the vase period. The fact that Ag was centred in basal stem end implied that the positive preservation effects of nano-silver on cut gerbera flowers is related to its strong and sustainable antiseptic action in the stem ends of cut flowers. The above results provide a reliable method for the determination of nano-silver and theoretical basis for its futher research and application in the preservation of cut flowers.


Subject(s)
Asteraceae/chemistry , Flowers/chemistry , Metal Nanoparticles/analysis , Silver/analysis , Spectrum Analysis
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