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The polyphosphoric acid (PPA) modified asphalt binder is a potential choice as one of the pavement materials for its excellent high-temperature performance and low cost. To further analyze the influences of temperature and load on the service life of pavement from the perspective of deformation behavior, six kinds of asphalt binders with different PPA dosages were prepared for Multiple Stress Creep and Recovery (MSCR) tests at five temperature levels. The deformation behavior is investigated by basic deformation parameters, rheological simulation, and energy parameter changes. The results show that the percent recovery (R) drops sharply while non-recoverable creep compliance (Jnr) goes up slightly with the increase in temperature. Three-element model, composed by E1, η1, and η2, can be used to describe the creep behavior. PPA-modified asphalt binder exhibits nonlinear creep behavior, and the logarithmic model can simulate recovery behavior better than the power-law model. Stored energy and dissipated energy can characterize the change of energy in the creep process under different conditions and show a significant correlation to deformation parameters. It is concluded that the elastic component of asphalt binders is increased by PPA, which is beneficial to the improvement of the deformation resistance and recovery capacity of asphalt binders. The recommended dosage of PPA is 1.5%. This investigation is conducive to a better understanding of the deformation behavior of PPA-modified asphalt binders and provides a reference for its engineering applications.
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AIMS: Nicotine, a major component of tobacco, is an important factor contributing to atherosclerosis. However, the molecular mechanisms underlying the link between nicotine and atherosclerosis are unclear. As extracellular vesicles (EVs) are involved in intercellular communication in atherosclerosis, we investigated whether their influence on arterial pathophysiology under nicotine stimulation. METHODS AND RESULTS: EVs from the serum of smokers (smoker-EVs) were significantly increased and exacerbated endothelial inflammation, as well as apoptosis according to functional studies. Meanwhile, inhibition of EVs blunted the nicotine-induced atherosclerosis progression, and injection of nicotine-induced EVs promoted atherosclerosis progression in ApoE-/- mice. Furthermore, quantitative reverse transcription-polymerase chain reaction analysis revealed a remarkable increase in miR-155 levels in smoker-EVs, which was correlated with carotid plaque formation in patients measured by ultrasound imaging. Moreover, CD14 levels were significantly increased in EVs from smokers (representing EVs derived from monocytes), indicating that monocytes are an important source of smoker-EVs. DNA methylation and the transcription factor HIF1α may contribute to increased miR-155 levels in monocytes, as assessed with bisulfite conversion sequencing and chromatin immunoprecipitation. Mechanistically, EVs encapsulated miR-155 induced endothelial cell dysfunction by directedly targeting BCL2, MCL1, TIMP3, BCL6, and activating NF-κB pathway, as verified in a series of molecular and biological experiments. Injecting EVs from nicotine-stimulated monocytes promoted plaque formation and triggered vascular endothelial injury in ApoE-/- mice, whereas inhibition of miR-155 weakened this effect. CONCLUSION: Our findings revealed an EV-dependent mechanism of nicotine-aggravated atherosclerosis. Accordingly, we propose an EV-based intervention strategy for atherosclerosis management.
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Aterosclerose , Vesículas Extracelulares , MicroRNAs , Camundongos , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Nicotina/toxicidade , Nicotina/metabolismo , Camundongos Knockout para ApoE , Aterosclerose/induzido quimicamente , Aterosclerose/genética , Aterosclerose/metabolismo , Vesículas Extracelulares/metabolismo , Apolipoproteínas E/genéticaRESUMO
OBJECTIVES: To explore the efficacy of microwave ablation (MWA) in the treatment of benign thyroid nodules, and analyze related influencing factors. METHODS: The clinical and ultrasound data of 115 patients with 115 benign thyroid nodules treated with MWA were retrospectively analyzed. The volume of nodules at 1, 3, 6, and 12 months after the procedure was obtained, and the volume reduction rate (VRR) at each time point was calculated. With VRR > 90% as the criterion for nodule cure, binary logistic regression was employed to screen the factors that affect the efficacy. RESULTS: â At 1, 3, 6, and 12 months after the procedure, the volume of nodules continued to decrease, the VRR gradually increased, and the differences at each time point were statistically significant (p < 0.05). A total of 29 (25.21%) nodules disappeared completely at 12 months after the procedure; â¡ Multivariate stepwise logistic regression showed that there was a statistically significant difference for the internal component of nodules, enhancement mode, and immediate volume after the procedure in determining the ablation efficacy (p < 0.05); ⢠The ROC curve was plotted for predicting the efficacy of MWA, with the results showing that the AUC, sensitivity, specificity, and accuracy were 0.82, 67.50, 88.00, 79.10%, respectively; ⣠11 cases (9.56%) had side effects, 10 cases (8.70%) had minor complications, and three cases (2.61%) had major complications. CONCLUSION: MWA is safe and effective in the treatment of benign thyroid nodules. The internal component of nodules, enhancement mode, and immediate volume after the procedure are independent factors that affect the efficacy of ablation.
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Ablação por Radiofrequência , Nódulo da Glândula Tireoide , Humanos , Micro-Ondas , Estudos Retrospectivos , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/cirurgia , Resultado do TratamentoRESUMO
Adiposederived stem cells (ADSCs) and bone marrowderived stem cells (BMSCs) are considered to be prospective sources of mesenchymal stromal cells (MSCs), that can be used in cell therapy for atherosclerosis. The present study investigated whether ADSCs cocultured with M1 foam macrophages via treatment with oxidized lowdensity lipoprotein (oxLDL) would lead to similar or improved antiinflammatory effects compared with BMSCs. ADSCs, peripheral blood monocytes, BMSCs and oxLDL were isolated from ten coronary heart disease (CHD) patients. After three passages, the supernatants of the ADSCs and BMSCs were collected and systematically analysed by liquid chromatographyquadrupole timeofflightmass spectrometry (6530; Agilent Technologies, Inc., Santa Clara, CA, USA). Cis9, trans11 was deemed to be responsible for the potential differences in the metabolic characteristics of ADSCs and BMSCs. These peripheral blood monocytes were characterized using flow cytometry. Following peripheral blood monocytes differentiation into M1 macrophages, the formation of M1 foam macrophages was achieved through treatment with oxLDL. Overall, 2x106 ADSCs, BMSCs or BMSCs+cis9, trans11 were cocultured with M1 foam macrophages. Antiinflammatory capability, phagocytic activity, antiapoptotic capability and cell viability assays were compared among these groups. It was demonstrated that the accumulation of lipid droplets decreased following ADSCs, BMSCs or BMSCs+cis9, trans11 treatment in M1 macrophages derived from foam cells. Consistently, ADSCs exhibited great advantageous antiinflammatory capabilities, phagocytic activity, antiapoptotic capability activity and cell viability over BMSCs or BMSCs+cis9, trans11. Additionally, BMSCs+cis9, trans11 also demonstrated marked improvement in antiinflammatory capability, phagocytic activity, antiapoptotic capability activity and cell viability in comparison with BMSCs. The present results indicated that ADSCs would be more appropriate for transplantation to treat atherosclerosis than BMSCs alone or BMSCs+cis9, trans11. This may be an important mechanism to regulate macrophage immune function.
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Tecido Adiposo/citologia , Células da Medula Óssea/metabolismo , Células Espumosas/metabolismo , Inflamação/etiologia , Inflamação/metabolismo , Lipoproteínas LDL/efeitos adversos , Células-Tronco Mesenquimais/metabolismo , Idoso , Apoptose , Células da Medula Óssea/citologia , Sobrevivência Celular , Citocinas/metabolismo , Feminino , Células Espumosas/citologia , Expressão Gênica , Perfilação da Expressão Gênica , Humanos , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Metabolismo dos Lipídeos , Macrófagos/metabolismo , Masculino , Células-Tronco Mesenquimais/citologia , Metaboloma , Metabolômica/métodos , Pessoa de Meia-IdadeRESUMO
Recently, elastography has become very popular in clinical investigation for thyroid cancer detection and diagnosis. In elastogram, the stress results of the thyroid are displayed using pseudo colors. Due to variation of the rendering results in different frames, it is difficult for radiologists to manually select the qualified frame image quickly and efficiently. The purpose of this study is to find the qualified rendering result in the thyroid elastogram. This paper employs an efficient thyroid ultrasound image segmentation algorithm based on neutrosophic graph cut to find the qualified rendering images. Firstly, a thyroid ultrasound image is mapped into neutrosophic set, and an indeterminacy filter is constructed to reduce the indeterminacy of the spatial and intensity information in the image. A graph is defined on the image and the weight for each pixel is represented using the value after indeterminacy filtering. The segmentation results are obtained using a maximum-flow algorithm on the graph. Then the anatomic structure is identified in thyroid ultrasound image. Finally the rendering colors on these anatomic regions are extracted and validated to find the frames which satisfy the selection criteria. To test the performance of the proposed method, a thyroid elastogram dataset is built and totally 33 cases were collected. An experienced radiologist manually evaluates the selection results of the proposed method. Experimental results demonstrate that the proposed method finds the qualified rendering frame with 100% accuracy. The proposed scheme assists the radiologists to diagnose the thyroid diseases using the qualified rendering images.
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OBJECTIVES: The aim of this work was to assess left ventricular (LV) regional systolic function in rabbits with myocardial infarction after allogeneic mesenchymal stem cell (MSC) transplantation using quantitative tissue velocity imaging. METHODS: Thirty New Zealand White rabbits were assigned into 3 groups randomly: a sham-operated group (n = 10), a myocardial infarction (MI) group (n = 10), and a MSC transplantation group (n = 10). Mesenchymal stem cells (1 × 10(7) in total) were delivered into 5 spots around the left anterior descending artery (LAD) blood supply area via direct intramyocardial injections 1 hour after LAD ligation in the MSC group, whereas the MI group received the same amount of phosphate-buffered saline injections. Echocardiography was performed before LAD ligation and 1 day and 2 weeks after MSC transplantation, respectively. The peak systolic velocity (Vs) of each LV wall segment was measured. The myocardial slices were harvested for histologic staining after the last echocardiographic examination. RESULTS: The velocity curves for the LV myocardium before LAD ligation had a trend showing that the Vs value decreased gradually from basal to apical segments. The Vs values for the LV segments around the infarcted area in the MSC group decreased significantly compared with the sham group (P < .05) 1 day after MSC transplantation, whereas they increased significantly 2 weeks after MSC transplantation compared with 1 day after LAD ligation (P < .05). CONCLUSIONS: This study demonstrates that quantitative tissue velocity imaging may provide a promising approach to quantitatively assessing LV regional systolic function before and after MSC transplantation.
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Ecocardiografia Doppler , Transplante de Células-Tronco Mesenquimais , Infarto do Miocárdio/diagnóstico por imagem , Disfunção Ventricular Esquerda/diagnóstico por imagem , Animais , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Infarto do Miocárdio/fisiopatologia , Coelhos , Disfunção Ventricular Esquerda/fisiopatologiaRESUMO
PURPOSE: The aim of this study was to identify the ultrasound features and clinicopathological characteristics of basal-like subtype of triple negative breast cancers (TNBCs). MATERIALS AND METHODS: This study was approved by the ethical board of the Second Affiliated Hospital of Harbin Medical University. The patients' clinicopathological information was available. The ultrasound features of 62 tumors from 62 TNBC patients were interpreted. The immunohistochemical results of cytokertain5/6 (CK5/6) and Epidermal Growth Factor Receptor (EGFR) were used to classify the tumor into basal-like and normal-like groups. The association of the ultrasound features interpreted by experienced ultrasound doctors with the immunohistochemical classification was studied. RESULTS: Of the 62 TNBC cases, 42 (67.7%) exhibited the basal-like phenotype and 20 (32.3%) exhibited the normal-like phenotype based on the immunohistochemical CK5/6 and EGFR markers. Of all the tumors, 90.3% were invasive carcinomas. The basal-like tumors were significantly associated with a maximum diameter on ultrasound of more than 20 mm (36, 85.7%) (P = 0.0014). The normal-like tumors usually exhibited lateral shadows (15, 75%) (P = 0.0115) as well as microlobulated margins (12, 60%) (P = 0.0204) compared to the basal-like subtype. Other ultrasound features showed no significant differences between the two groups. CONCLUSIONS: Although ultrasound cannot yet be used to differentiate between the basal-like subtype and normal-like subtype of TNBC, ultrasound can be used to provide some useful information to the clinicians.
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Neoplasias de Mama Triplo Negativas/diagnóstico por imagem , Neoplasias de Mama Triplo Negativas/patologia , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Carcinoma/diagnóstico por imagem , Carcinoma/patologia , Receptores ErbB/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Queratina-5/metabolismo , Queratina-6/metabolismo , Modelos Logísticos , Pessoa de Meia-Idade , Fenótipo , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , UltrassonografiaRESUMO
PURPOSE: The aim of the study was to evaluate the correlation of ultrasound features with breast cancer molecular status. MATERIALS AND METHODS: A retrospective review was performed of ultrasound findings in 263 patients diagnosed with breast invasive ductal carcinoma for comparison with immunohistochemistric results were obtained from each lesion. Relationships between ultrasound findings and molecular status were investigated by using multiple regression analysis by means of stepwise logistic regression. Differences in ultrasound criteria were assessed among women with different molecular status. RESULTS: ER positivity was associated with small size, lobulate, angular or spiculated margin contours, absence of calcification, posterior tumor shadowing and low elasticity score; PR positivity was associated with small size, lobulate or angular or spiculated margin contours and absence of calcification; HER2 positivity was associated with presence of calcification and absence of any echogenic halo. The calculated models of predicted molecular status were accurate and discriminating with AUCs of 0.78, 0.74, and 0.74, respectively. CONCLUSIONS: Breast cnacer ultrasound features show some correlation with the molecular status. These models may help to expand the scope of ultrasound in predicting tumor biology.
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Neoplasias da Mama/diagnóstico por imagem , Ultrassonografia Mamária/estatística & dados numéricos , Adulto , Idoso , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Estudos Retrospectivos , Adulto JovemRESUMO
To study the association between known risk factors for cardiovascular disease and intima-media thickness (IMT) in the carotid and popliteal arteries in middle-aged and elderly Chinese adults. 686 middle aged and elderly Chinese adults from the China Da Qing Diabetes Prevention Study who had full clinical, laboratory, ultrasound examination results were enrolled in the study. Common carotid artery (CCA) and popliteal artery (PA) IMT were obtained using high resolution ultrasound machine. Pearson's or Spearman's correlation analysis and logistic regression analysis were used to determine association between risk factors [age, gender, tobacco smoking, body mass index (BMI), diabetes mellitus (DM), systolic blood pressure (SBP), diastolic blood pressure (DBP), total cholesterol, total triglyceride, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol, glycosylated hemoglobin (HbA1c)] and CCA- or PA-IMT. The age range of the study population was 45-87 years, 384 of them (56 %) were women. The prevalence of high blood pressure and DM was 60.6 and 68.8 %, respectively. Participants in DM group tended to be older, had greater value for SBP, HbA1c and PA-IMT, but smaller value for DBP than those in control group. Smoke status, BMI, blood lipids and CCA-IMT were not statistically different between groups. Pearson's or Spearman's rank correlation analysis showed that CCA-IMT had a positive correlation with age, gender, DM, SBP, BMI and HbA1c, negative correlation with HDL-C. PA-IMT showed a positive correlation with age, gender and SBP. Univariate logistic regression analysis showed that elevation of age, SBP, BMI, HbA1c and having DM were significant predictors of CCA-IMT thickening, so was reduction of HDL-C. Risk factors that predicted significant thickening of PA-IMT were age, gender, tobacco smoking. After adjusted for age and gender, except HDL-C, the other four risk factors (SBP, BMI, HbA1c and having DM) that predicted CCA-IMT thickening remained significant; however none of the risk factors predicted PA-IMT thickening after adjusted for age and gender. The current results provide evidence that CCA-IMT is a superior marker for atherosclerosis compared with PA-IMT. Aggressive control of SBP, HbA1c and proper control of weight may postpone thickening of CCA-IMT.
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Doenças das Artérias Carótidas/diagnóstico por imagem , Espessura Intima-Media Carotídea , Doença Arterial Periférica/diagnóstico por imagem , Artéria Poplítea/diagnóstico por imagem , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , Doenças das Artérias Carótidas/etnologia , Doenças das Artérias Carótidas/prevenção & controle , Distribuição de Qui-Quadrado , China/epidemiologia , Diabetes Mellitus/etnologia , Feminino , Humanos , Hipertensão/etnologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Obesidade/etnologia , Razão de Chances , Doença Arterial Periférica/etnologia , Doença Arterial Periférica/prevenção & controle , Valor Preditivo dos Testes , Prevalência , Fatores de RiscoRESUMO
OBJECTIVE: To assess the clinical value of strain ratio in differentiating thyroid solid nodules and explore its distribution characters based on pathological results. MATERIALS AND METHODS: The study was approved by the ethic committee and the informed consents were signed. Ninety nine solid thyroid nodules (67 benign and 32 malignant) from 71 female (mean age 46.3 ± 9.8 years) and 28 male (mean age 54.9 ± 11.7 years) patients were evaluated. Five radiologists evaluated the nodules based on a four-degree elastography score system. Strain ratio was calculated on-line. Diagnostic performances of the two evaluations were compared using Receiver Operating Characteristic (ROC) curves. Values of different pathological nodules were compared by one-way ANOVA. RESULTS: Areas under the ROC curve (AUC) of the five readers were 0.82, 0.81, 0.79, 0.73 and 0.83, respectively. The AUC of strain ratio evaluation was higher (0.88 vs. 0.79, p < 0.001) than that of the ES score evaluation. Best cut-off points of the two evaluations were 3.5 (82% sensitivity, 72% specificity) and 4.225 (81% sensitivity, 83% specificity), respectively. Both the ES score and strain ratio were higher for malignant nodules than that for benign ones (p < 0.001). CONCLUSIONS: Strain ratio was a useful index in differential diagnosis of thyroid solid nodules. It can provide quantitative information on thyroid nodule characterization and improve diagnostic confidence. The best cut-off point for benign and malignant nodules was 4.2.
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Técnicas de Imagem por Elasticidade/métodos , Interpretação de Imagem Assistida por Computador/métodos , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/fisiopatologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anisotropia , Criança , Módulo de Elasticidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto JovemRESUMO
For a successful computer-aided diagnosis (CAD) approach, investigating the benefit of the output for radiologist diagnosis is as important as developing the computer algorithm itself. To evaluate the accuracy and the interobserver variability of two newly developed CAD algorithms for breast mass discrimination, eight radiologists with varied experience in breast ultrasonography (US) independently reviewed the lesions according to Breast Imaging Reporting and Data System (BI-RADS)-US. They interpreted the original ultrasound images, provided a final assessment category to indicate the probability of malignancy and then made a further diagnosis using the images processed by the proposed CAD algorithms. The receiver operating characteristic (ROC) curve and Cohen's kappa statistics were employed to evaluate the effect of the CAD algorithms on radiologist diagnoses. By using the proposed CAD approach, the quality of the images was improved and more information was provided to the observers. With the processed images, the areas under the ROC (Az) of each reader (0.86 approximately 0.89) were greater than those with the original ultrasound images (0.81 approximately 0.86) and all the radiologists improved their performance significantly (p < 0.05) except two senior radiologists (p > 0.05). The Az values of the junior radiologists with CAD were comparable to those of the senior radiologists. Cohen's kappa statistics showed that better interobserver agreement was obtained by using the processed images. We conclude that the proposed CAD method is more helpful for the junior radiologists than for the senior ones and it also showed the advantage of decreasing interobserver variability.