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1.
Neurochem Res ; 49(4): 815-833, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38170383

RESUMO

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.


Assuntos
Ferroptose , Sobrecarga de Ferro , AVC Isquêmico , Humanos , Ácido Glutâmico , Peroxidação de Lipídeos , Espécies Reativas de Oxigênio
2.
Plant Physiol ; 169(4): 2391-408, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26514808

RESUMO

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.


Assuntos
Antocianinas/metabolismo , Catequina/metabolismo , Frutas/enzimologia , Lacase/metabolismo , Litchi/enzimologia , Catecol Oxidase/metabolismo , Frutas/citologia , Frutas/genética , Frutas/fisiologia , Lacase/genética , Litchi/citologia , Litchi/genética , Litchi/fisiologia , Modelos Moleculares , Oxirredução , Fenóis/metabolismo , Filogenia , Folhas de Planta/citologia , Folhas de Planta/enzimologia , Folhas de Planta/genética , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Nicotiana/genética , Nicotiana/fisiologia
3.
PLoS One ; 19(3): e0298378, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38427661

RESUMO

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.


Assuntos
Terapia Comportamental , Políticas , Humanos , Inquéritos e Questionários
4.
Chin Med Sci J ; 27(4): 195-200, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23294583

RESUMO

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.


Assuntos
Fibrilação Atrial , Angiografia Coronária , Eletrocardiografia , Humanos , Estudos Prospectivos , Doses de Radiação , Tomografia Computadorizada Espiral
5.
Zhonghua Xin Xue Guan Bing Za Zhi ; 41(5): 411-5, 2013 May.
Artigo em Chinês | MEDLINE | ID: mdl-24021125

RESUMO

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.


Assuntos
Angiografia por Ressonância Magnética/métodos , Placa Aterosclerótica/diagnóstico , Animais , Modelos Animais de Doenças , Suínos , Porco Miniatura
6.
Zhonghua Yi Xue Za Zhi ; 92(47): 3336-40, 2012 Dec 18.
Artigo em Chinês | MEDLINE | ID: mdl-23328594

RESUMO

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.


Assuntos
Fístula Artério-Arterial/diagnóstico por imagem , Doença da Artéria Coronariana/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Fístula Artério-Arterial/classificação , Criança , Angiografia Coronária , Doença da Artéria Coronariana/classificação , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
7.
Am J Chin Med ; 50(1): 313-332, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34963428

RESUMO

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.


Assuntos
Carcinoma Hepatocelular , Ácido Glicirretínico , Neoplasias Hepáticas , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Transição Epitelial-Mesenquimal , Ácido Glicirretínico/farmacologia , Humanos , Neoplasias Hepáticas/patologia , Invasividade Neoplásica , Fator de Transcrição STAT3/metabolismo , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(8): 2253-5, 2011 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-22007427

RESUMO

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.


Assuntos
Asteraceae/química , Flores/química , Nanopartículas Metálicas/análise , Prata/análise , Análise Espectral
9.
Bioact Mater ; 6(12): 4729-4757, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34136723

RESUMO

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.

10.
Mol Plant ; 14(7): 1149-1167, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-33857689

RESUMO

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.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Hidrolases de Éster Carboxílico/metabolismo , Proteínas de Choque Térmico/metabolismo , Luz , Metaloendopeptidases/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Folhas de Planta/efeitos da radiação , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/efeitos da radiação , Fotossíntese , Folhas de Planta/enzimologia , Protetores contra Radiação , Tilacoides/metabolismo
11.
Bioact Mater ; 5(2): 398-409, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32258829

RESUMO

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.

12.
Bioact Mater ; 5(2): 318-333, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32181417

RESUMO

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.

13.
Mol Oncol ; 13(4): 792-810, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30556279

RESUMO

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.


Assuntos
Carcinogênese/patologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Transição Epitelial-Mesenquimal , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Idoso , Animais , Caderinas/metabolismo , Carcinogênese/genética , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Ciclina D1/metabolismo , Ativação Enzimática , Feminino , Regulação Neoplásica da Expressão Gênica , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Metástase Neoplásica , Estabilidade Proteica , Fatores de Transcrição da Família Snail/metabolismo , Regulação para Cima/genética , beta Catenina/metabolismo
14.
AJR Am J Roentgenol ; 191(6): 1734-9, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19020244

RESUMO

OBJECTIVE: The purpose of this study was to evaluate the potential for improving the image quality of 3D bolus-chase peripheral MR angiography by injecting contrast medium at a slow rate. SUBJECTS AND METHODS: Using similar imaging parameters in all cases, we performed bolus-chase MR angiography of the abdominal and lower limb arteries of 80 patients. The injection protocol for 40 patients had three parts: 20 mL of gadopentetate dimeglumine at 2 mL/s, 8 mL of gadopentetate dimeglumine at 1 mL/s, and 20 mL of saline solution at 1 mL/s. For the other 40 patients, the injection protocol was 20 mL of gadopentetate dimeglumine at 1.2 mL/s, 8 mL of gadopentetate dimeglumine at 0.7 mL/s, and 20 mL of saline solution at 0.7 mL/s. Using independent Student's t tests between groups, we compared signal-to-noise and contrast-to-noise ratios in the abdomen and pelvis, the thigh, and the calf. Arterial visibility and venous contamination on 3D images of the calf were graded and compared. RESULTS: The lower injection rate increased arterial visibility (p < 0.001), reduced venous contamination in the calf (p < 0.001), and increased the contrast-to-noise ratio in the calf (p < 0.001). At the upper levels, signal-to-noise and contrast-to-noise ratios did not differ between the two groups. CONCLUSION: At 3-T MRI, a lower injection rate may alleviate venous contamination and increase arterial visibility in the calf while signal-to-noise and contrast-to-noise ratios at higher levels are maintained.


Assuntos
Arteriopatias Oclusivas/diagnóstico , Gadolínio DTPA/administração & dosagem , Aumento da Imagem/métodos , Angiografia por Ressonância Magnética/métodos , Doenças Vasculares Periféricas/diagnóstico , Adulto , Idoso , Meios de Contraste/administração & dosagem , Extravasamento de Materiais Terapêuticos e Diagnósticos/prevenção & controle , Feminino , Humanos , Injeções Intravenosas , Perna (Membro)/irrigação sanguínea , Perna (Membro)/patologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Veias/patologia
15.
J Interv Card Electrophysiol ; 22(3): 199-203, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18459040

RESUMO

BACKGROUND AND OBJECTIVE: Recent advances in multi-slice computed tomography (MSCT) have allowed an improved analysis of left atrial (LA) and left atrial appendage (LAA) anatomy prior to catheter ablation of atrial fibrillation (AF). However, data regarding the ability of MSCT to identify LA/LAA thrombus are limited. This prospective study compared the efficacy of 64-slice contrast-enhanced computed tomography (64CCT) with transesophageal echocardiography (TEE) of the heart in the identification of LA/LAA thrombus. MATERIALS AND METHODS: One-hundred and seventy consecutive patients scheduled for first-time catheter ablation of paroxysmal (n = 120) or persistent (n = 50) AF were enrolled for study. Each patient underwent non-gated 64CCT and TEE of the heart for exclusion of LA/LAA thrombus prior to ablation procedure. RESULTS: Fourteen cases (8.2%) of LA/LAA thrombi were interpreted by 64CCT (ten false-positive, four true positive), whereas 11 actual thrombi (6.5%) were detected by TEE (seven false-negative by 64CCT) in the same population. Maximal dimension of TEE identified thrombi did not differ between the false-negative by 64CCT group and the true-positive group (17 +/- 6 vs. 18 +/- 5 mm P = 0.677). Results indicated 64CCT sensitivity = 36.4%, specificity = 93.7%, positive predictive value = 28.6%, and negative predictive value = 95.5% in the detection of LA/LAA thrombus. The Kappa value in evaluating the agreement between 64CCT and TEE for detection of LA/LAA thrombus was 0.267. CONCLUSION: Compared to gold standard TEE, 64CCT was shown to be less reliable in the detection of LA/LAA thrombus prior to catheter ablation in patients with AF.


Assuntos
Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Ecocardiografia Transesofagiana/métodos , Átrios do Coração/diagnóstico por imagem , Cardiopatias/diagnóstico , Trombose/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Zhonghua Nei Ke Za Zhi ; 47(3): 202-5, 2008 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-18785502

RESUMO

OBJECTIVE: To prospectively investigate the neurological complications (NC) after off-pump coronary artery bypass grafting (OPCABG), including the kinds of NC and their mobility, risk factors, prevention and treatment. METHODS: A total of 55 consecutive patients with undergoing OPCABG were evaluated from March to June 2006 at the Department of Cardiosurgery in Beijing Anzhen Hospital. Risk factors of NC were collected before operation. Nervous system physical examination, the NIH Stroke Scale (NIHSS) score evaluation, cognitive tests, imaging examination (MRI, MRA and f-MRI), anxious and depression scale were performed before and after OPCABG. NC and their kinds were identified after surgery. According to the presence or absence of NC after the operation, the patients were divided into two groups, and univariate analysis was used between the two groups. P < 0.05 was considered of statistically significant difference. RESULTS: (1) 2 cases of ischemic stroke developed after surgery (2/55), but there no case of mortality. The risk factors were not statistically different between the two groups (P > 0.05); (2) For all the patients, cognitive evaluation was normal and unchanged before and after surgery (P > 0.05), including Mini-Mental State Examination (MMSE), Clinical dementia rating (CDR) and Global Deterioration Scale (GDS); (3) Except the 2 cases of stroke, the others were normal and had no change on MRI, MRA, and f-MRI (P > 0.05) before and after surgery; (4) 7 patients with slight anxiety and one with slight depression before operation recovered completely after surgery without treatment. Both the Self-rating Anxiety Scale (SAS) and Self-rating Depression Scale (SDS) were normal and unchanged before and after surgery (P > 0.05). CONCLUSIONS: 2 cases of ischemic stroke were found among 55 patients undergoing OPCABG (2/55) and there was no mortality. There was no obvious change of cognitive function, imaging finding, anxiety and depression before and after the operation (P > 0.05). OPCABG is relatively safe for nervous system, but more exploratory work and clinical data are needed.


Assuntos
Ponte de Artéria Coronária sem Circulação Extracorpórea/efeitos adversos , Transtornos Mentais/diagnóstico , Complicações Pós-Operatórias/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/etiologia , Isquemia Encefálica/prevenção & controle , Feminino , Humanos , Masculino , Transtornos Mentais/tratamento farmacológico , Transtornos Mentais/prevenção & controle , Pessoa de Meia-Idade , Exame Neurológico , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Estudos Prospectivos
17.
Sci Rep ; 8(1): 9365, 2018 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-29921924

RESUMO

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.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Carcinoma Hepatocelular/metabolismo , Ácido Glicirretínico/análogos & derivados , Neoplasias Hepáticas/metabolismo , Resposta a Proteínas não Dobradas/genética , Apoptose/genética , Autofagia/genética , Carcinoma Hepatocelular/genética , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Endorribonucleases/genética , Endorribonucleases/metabolismo , Fase G1/efeitos dos fármacos , Fase G1/genética , Ácido Glicirretínico/farmacologia , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Fase de Repouso do Ciclo Celular/genética , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Proteína 1 de Ligação a X-Box/genética , Proteína 1 de Ligação a X-Box/metabolismo
18.
Zhonghua Yi Xue Za Zhi ; 87(16): 1113-6, 2007 Apr 24.
Artigo em Chinês | MEDLINE | ID: mdl-17672993

RESUMO

OBJECTIVE: To analyze characteristic imagery of renal cell carcinoma with distinct histological subtypes and to increase the level of the diagnose and treatment in renal cell carcinoma. METHODS: 32 cases of parenchymatous renal cell cancer consisting of 26 conventional clear cell renal cell carcinoma, 5 cases of indolent papillary and 1 case of chromophobe carcinomas were compared with the different imagery features. RESULTS: All parenchymatous renal cell cancer patients underwent ultrasound, renal lesions showed parenchymatous echo of cortex renis. Most of the clear-cell carcinoma (20/26) demonstrated a low echo-level, papillary carcinoma (4/5) showed an ambly-high-level echo, chromophobe carcinoma showed a high-level echo. There was a significant differences the echo level between the conventional clear cell renal cell carcinoma and nonconventional clear cell RCC (P=0.005). 29 of 32 case, including 23 cases of conventional clear cell tumors and 6 cases of nonconventional clear cell RCC, underwent CT scanning: all renal lesions showed soft tissue density, but there was a significant difference between conventional and nonconventional clear cell renal cell carcinoma in contrast enhancement in either inhomogeneous enhancement (22/23 vs 3/6, P=0.004). 17 cases (11 with conventional clear cell renal cell carcinoma, 1 with chromophobe carcinoma and 5 with papillary carcinoma) underwent MRI. 10 of the conventional clear cell renal cell carcinoma showed hyperintense on T2WI (10/11) cases papillary tumor showed hypointensity on T2WI (5/5) them (P<0.01). CONCLUSION: The different imagery features in conventional and nonconventional clear cell renal cell carcinoma according to preoperative imaging examination (ultrasound and computed tomography and magnetic resonance imaging) are helpful in the diagnosis and treatment of renal cell carcinoma.


Assuntos
Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Carcinoma de Células Renais/diagnóstico por imagem , Diagnóstico por Imagem , Feminino , Humanos , Neoplasias Renais/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Ultrassonografia
19.
Sci Rep ; 7(1): 16674, 2017 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-29192231

RESUMO

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.


Assuntos
Etilenos/metabolismo , Frutas/genética , Regulação da Expressão Gênica de Plantas , Pigmentação/genética , Solanum lycopersicum/genética , Fatores de Transcrição/genética , Perfilação da Expressão Gênica , Inativação Gênica , Genes Reporter , Estudos de Associação Genética , Interações Hospedeiro-Patógeno , Solanum lycopersicum/classificação , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/virologia , Fenótipo , Filogenia , Regiões Promotoras Genéticas , Ligação Proteica , Transporte Proteico , Fatores de Transcrição/metabolismo , Ativação Transcricional , Transcriptoma
20.
Acad Radiol ; 13(10): 1180-6, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16979066

RESUMO

RATIONALE AND OBJECTIVES: We sought to test the hypothesis that magnetic resonance imaging (MRI)-defined vulnerable plaques correlate to accelerated reoccurrence of cerebrovascular events and to evaluate the potential use of MRI in secondary prevention of ischemic stroke. MATERIALS AND METHODS: Fifty-three symptomatic participants were recruited from patients sustaining their second MRI-confirmed cerebral infarction. Nine participants were women and 44 were men; the mean age was 69.2 years (range, 55-94 years). Patients were imaged within 7 days after the reoccurrence of cerebral infarction. The MRI diagnostic signals defined a classification of lesion type. We compare the interval between two cerebral infarctions with plaque vulnerability defined by the MRI lesion type. We used a Cox proportional hazards model to calculate the relationship between vulnerable lesions and the interval of cerebral infarction, and we followed these patients for 180 days and compared the recurrent rate for the third-time cerebral infarction between patients with and without vulnerable plaque. RESULTS: The mean infarction recurrence interval for patients with vulnerable lesions was shorter than the mean interval for patients without vulnerable lesion (310.1 versus 1697.2, P< .001). In patients with recurrent cerebral infarction within 1 year, vulnerable lesions were more frequently detected (76% versus 19%, P< .001). The patients with vulnerable lesions had an 8.8-fold higher hazard risk (8.8; P< .001, 95% confidence interval, 3.9-19.7) than those without vulnerable lesions after adjustment for risk factors. For those with vulnerable plaque, the morbidity of third-time cerebral infarction was higher than those without (24% versus 3%, P = .023). CONCLUSION: MRI-defined vulnerable lesions in carotid arteries are related to accelerated recurrent cerebral infarction and high recurrent rate. MRI demonstrates clinical value in the secondary prevention of cerebral infarction.


Assuntos
Doenças das Artérias Carótidas/complicações , Doenças das Artérias Carótidas/diagnóstico , Infarto Cerebral/diagnóstico , Infarto Cerebral/prevenção & controle , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Medição de Risco/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Reprodutibilidade dos Testes , Fatores de Risco , Prevenção Secundária , Sensibilidade e Especificidade
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