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PURPOSE: To evaluate the predictive performance of multiparameter and histogram features derived from amide proton transfer-weighted imaging (APTWI), intravoxel incoherent motion (IVIM) and diffusion kurtosis imaging (DKI) for histopathological types of breast tumors. METHODS: Region of interest (ROI) was delineated by outlining the largest slice of the tumor on the false-color images of the DKI, IVIM and APTWI parameters, and extracted the histogram features. Receiver operating characteristic (ROC) curve was used to evaluate the performance of parameters in predicting benign and malignant breast lesions, molecular prognostic biomarkers, lymph node status, and subtypes of breast lesions. The Spearman correlation coefficient was used to determine the correlations between each parameter and clinical-pathological factors. RESULTS: All 52 breast lesions were enrolled in this prospective study, including 8 benign lesions and 44 breast cancers. To diagnose malignant and benign breast lesions, the value of APT (min) performed best, with the AUC reaching 0.983. According to the different imaging methods, the APTWI performed best. To predict the positive status of ER, PR, Ki67, the value of Dapp (uniformity), Dapp (uniformity), f (entropy) performed best, with the AUC values reaching 0.743, 0.770, 0.848, respectively. For the identification of Luminal B, HER2-enriched, and TNBC breast cancers, Kapp (max), f (kurtosis), and Dapp (uniformity) performed best, with AUC values reaching 0.679, 0.826, 0.771, respectively. CONCLUSION: This study found the APTWI, IVIM and DKI parameters could diagnose breast cancer. The histogram features of DKI and IVIM, based on tumor heterogeneity, may help to predict breast cancer subtypes.
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Neoplasias da Mama , Neoplasias Mamárias Animais , Humanos , Animais , Feminino , Prótons , Imagem de Difusão por Ressonância Magnética/métodos , Estudos Prospectivos , Imagem de Tensor de Difusão/métodos , Neoplasias da Mama/diagnóstico por imagem , Movimento (Física)RESUMO
BACKGROUND: Siamese network (SN) using longitudinal DCE-MRI for pathologic complete response (pCR) identification lack a unified approach to phases selection. PURPOSE: To identify pCR in early-stage NAC, using SN with longitudinal DCE-MRI and introducing IPS for phases selection. STUDY TYPE: Multicenter, longitudinal. POPULATION: Center A: 162 female patients (50.63 ± 8.41 years) divided 7:3 into training and internal validation cohorts. Center B: 61 female patients (50.08 ± 7.82 years) were used as an external validation cohort. FIELD STRENGTH/SEQUENCE: Center A: single vendor 3.0 T with a compressed-sensing volume interpolated breath-hold examination sequence. Center B: single vendor 1.5 T with volume interpolated breath-hold examination sequence. ASSESSMENT: Patients underwent DCE-MRI before and after two NAC cycles, with tumor regions of interest (ROI) manually delineated. Histopathology was the reference for pCR identification. Models developed included a clinical one, four SN models based on IPS-selected phases, and integrated models combining clinical and SN features. STATISTICAL TESTS: Model performance was evaluated using the area under the receiver operating characteristic curve (AUC). The DeLong test was used to compare AUCs. Net reclassification improvement and integrated discrimination improvement (IDI) tests were employed for performance comparison. P < 0.05 was considered significant. RESULTS: In internal and external validation cohorts, the clinical model showed AUCs of 0.760 and 0.718. SN and integrated models, with increasing phases via IPS, achieved AUCs ranging from 0.813 to 0.951 and 0.818 to 0.922. Notably, SN-3 and integrated-3 and integrated-4 outperformed the clinical model. However, input phases beyond 20% did not significantly enhance performance (IDI test: SN-4 vs. SN-3, P = 0.314 and 0.630; integrated-4 vs. integrated-3, P = 0.785 and 0.709). DATA CONCLUSION: The longitudinal multiphase DCE-MRI based on the SN demonstrates promise for identifying pCR in breast cancer. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 4.
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The purpose of this study was to explore the effectiveness of radiomics based on multisequence MRI in predicting the expression of PD-1/PD-L1 in hepatocellular carcinoma (HCC). One hundred and eight patients with HCC who underwent contrast-enhanced MRI 2 weeks before surgical resection were enrolled in this retrospective study. Corresponding paraffin sections were collected for immunohistochemistry to detect the expression of PD-1 and PD-L1. All patients were randomly divided into a training cohort and a validation cohort at a ratio of 7:3. Univariate and multivariate analyses were used to select potential clinical characteristics related to PD-1 and PD-L1 expression. Radiomics features were extracted from the axial fat-suppression T2-weighted imaging (FS-T2WI) images and the arterial phase and portal venous phase images from the axial dynamic contrast-enhanced MRI, and the corresponding feature sets were generated. The least absolute shrinkage and selection operator (LASSO) was used to select the optimal radiomics features for analysis. Logistic regression analysis was performed to construct single-sequence and multisequence radiomics and radiomic-clinical models. The predictive performance was judged by the area under the receiver operating characteristic curve (AUC) in the training and validation cohorts. In the whole cohort, PD-1 expression was positive in 43 patients, and PD-L1 expression was positive in 34 patients. The presence of satellite nodules served as an independent predictor of PD-L1 expression. The AUC values of the FS-T2WI, arterial phase, portal venous phase and multisequence models in predicting the expression of PD-1 were 0.696, 0.843, 0.863, and 0.946 in the training group and 0.669, 0.792, 0.800 and 0.815 in the validation group, respectively. The AUC values of the FS-T2WI, arterial phase, portal venous phase, multisequence and radiomic-clinical models in predicting PD-L1 expression were 0.731, 0.800, 0.800, 0.831 and 0.898 in the training group and 0.621, 0.743, 0.771, 0.810 and 0.779 in the validation group, respectively. The combined models showed better predictive performance. The results of this study suggest that a radiomics model based on multisequence MRI has the potential to predict the preoperative expression of PD-1 and PD-L1 in HCC, which could become an imaging biomarker for immune checkpoint inhibitor (ICI)-based treatment.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Antígeno B7-H1 , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Imageamento por Ressonância Magnética/métodos , Receptor de Morte Celular Programada 1 , Estudos RetrospectivosRESUMO
Background: Hepatocellular carcinoma (HCC) is the fourth most common cause of cancer-related death worldwide. Angiogenic factors may be valuable indices of tumor recurrence and treatment and potentially useful markers for predicting the response to antiangiogenesis therapy. Vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs) are major drivers of tumor angiogenesis. Preoperatively predicting the expression of VEGF and MMPs is crucial for treating HCC. Intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) has been successfully used in the differential diagnosis of HCC, pathological grading, and treatment response evaluation. However, the correlations between IVIM-DWI parameters and VEGF and MMP expression have not been reported. This study provides a preliminary analysis of the correlation between IVIM-DWI parameters and the expression of VEGF, MMP-2, and MMP-9 to investigate the value of IVIM-DWI in the noninvasive evaluation of angiogenesis in HCC. Methods: IVIM-DWI was performed in 61 patients with HCC 1 week before they underwent surgical resection. VEGF, MMP-2, and MMP-9 expression was detected using immunohistochemistry staining. Spearman correlation analysis was used to analyze the correlations between the IVIM-DWI parameters and VEGF, MMP-2, and MMP-9 expression in HCC. Results: The fast apparent diffusion coefficient fraction (f) value was positively correlated with the expression of VEGF (P<0.001), MMP-2 (P=0.002), and MMP-9 (P<0.001). The fast apparent diffusion coefficient (D*) was positively correlated with VEGF (P<0.001) and MMP-9 (P<0.001) expression but was not correlated with MMP-2 (P=0.659) expression. The apparent diffusion coefficient (ADC) and slow apparent diffusion coefficient (D) values were not significantly correlated with the expression of VEGF (P=0.103 and P=0.543, respectively), MMP-2 (P=0.596 and P=0.338, respectively), or MMP-9 (P=0.102 and P=0.660, respectively). Conclusions: IVIM-DWI can be used to noninvasively evaluate angiogenesis in HCC.
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Oxygen vacancies (OVs) on specific sites/facets can strengthen the interaction between reactants and oxide surfaces, facilitating interfacial charge transfer. However, precise monitoring of the spatial distribution of OVs remains a grand challenge. We report here that a single-particle spectroscopy technique addresses this challenge by establishing a positive correlation relationship between defects and bound exciton luminescence across different facets. Taking monoclinic BiVO4 as an example, on the basis of theoretical guidance, by in situ tracking the PL lifetimes and PL spectra of different facets on single particles before and after hydrogen treatment, we provide evidence that the PL emission originates from the OV state and determine that OVs is more inclined to be generated at the {010} facets. This anisotropic defect engineering significantly prolongs the lifetime of carriers and accelerates the activation of molecular oxygen. These findings not only verify preference rules of OVs in metal oxides but also provide a time-space-resolved monitoring method.
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Hepatocellular carcinoma (HCC) is the sixth most common malignant tumour and the third leading cause of cancer death in the world. The emerging field of radiomics involves extracting many clinical image features that cannot be recognized by the human eye to provide information for precise treatment decision making. Radiomics has shown its importance in HCC identification, histological grading, microvascular invasion (MVI) status, treatment response, and prognosis, but there is no report on the preoperative prediction of programmed death ligand-2 (PD-L2) expression in HCC. The purpose of this study was to investigate the value of MRI radiomic features for the non-invasive prediction of immunotherapy target PD-L2 expression in hepatocellular carcinoma (HCC). A total of 108 patients with HCC confirmed by pathology were retrospectively analysed. Immunohistochemical analysis was used to evaluate the expression level of PD-L2. 3D-Slicer software was used to manually delineate volumes of interest (VOIs) and extract radiomic features on preoperative T2-weighted, arterial-phase, and portal venous-phase MR images. Least absolute shrinkage and selection operator (LASSO) was performed to find the best radiomic features. Multivariable logistic regression models were constructed and validated using fivefold cross-validation. The area under the receiver characteristic curve (AUC) was used to evaluate the predictive performance of each model. The results show that among the 108 cases of HCC, 50 cases had high PD-L2 expression, and 58 cases had low PD-L2 expression. Radiomic features correlated with PD-L2 expression. The T2-weighted, arterial-phase, and portal venous-phase and combined MRI radiomics models showed AUCs of 0.789 (95% CI: 0.702-0.875), 0.727 (95% CI: 0.632-0.823), 0.770 (95% CI: 0.682-0.875), and 0.871 (95% CI: 0.803-0.939), respectively. The combined model showed the best performance. The results of this study suggest that prediction based on the radiomic characteristics of MRI could noninvasively predict the expression of PD-L2 in HCC before surgery and provide a reference for the selection of immune checkpoint blockade therapy.
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In our recent work (ACS Sens.2022, 7, 1095-1104), Mirabella et al. provided comments on our publication, mainly focusing on the controversy between the oxygen vacancy model and the ionosorbed model and the related derivation based on the law of mass action. Herein we explain the correlation between the ionosorption model and the oxygen vacancy model and provide a brief introduction of our view on these two models. Moreover, a more detailed derivation about the law of mass action is provided to explain the relationship between surface electron concentration, oxygen partial pressure, adsorbed oxygen density, and oxygen vacancy density.
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Elétrons , Oxigênio , Pressão ParcialRESUMO
Photocatalytic CO2 cycloaddition is a promising approach for CO2 value-added processes. However, the efficiency of plasmon-assisted CO2 cycloaddition still needs to be improved and the reaction mechanism is unclear. Herein, g-C3N4/Ag (ACN-Ag) hybrids exhibited superior activity of CO2 cycloaddition by coupling a semiconductor into the plasmonic system, in which the ACN grafting amino group by the formation of carbon vacancies can enhance CO2 chemisorption; meanwhile, photo-generated electrons from ACN transfer to Ag to form high-energy electrons, which can activate propylene oxide, accelerating the ring-opening step. Importantly, photo-generated electron injection from ACN to Ag and the interaction between Ag nanoparticles and ACN were confirmed by single-particle photoluminescence spectroscopy. The wavelength-dependent activity demonstrated that the plasmon excitation is crucial for the reaction. Moreover, in situ single-particle PL quenching caused by propylene oxide and in situ electron paramagnetic resonance verified the activation of propylene oxide by ACN-Ag. This work is conducive to an in-depth understanding of the mechanism of CO2 cycloaddition at the single-particle level and provides guidance for the organic synthesis.
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BACKGROUND: A cervical aortic arch (CAA) refers to a high-riding aortic arch (AA) that often extends above the level of the clavicle. This condition is very rare, with an incidence of less than 1/10000. CASE SUMMARY: A 29-year-old woman was admitted to the otolaryngology department of our hospital for repeated bilateral purulent nasal discharge for the prior 3 mo. The patient was diagnosed with chronic sinusitis and chronic rhinitis at admission. A preoperative noncontrast chest computed tomography scan showed a high-riding, tortuous AA extending to the mid-upper level of the first thoracic vertebra with local cystic dilatation. A further computed tomography angiography examination showed that the brachiocephalic trunk, left common carotid artery, left vertebral artery (LVA) (slender), and left subclavian artery sequentially branched off of the aorta from the proximal end to the distal end of the AA. The proximal end of the right subclavian artery (RSCA) was tortuous and dilated. The AA showed tumor-like local expansion, with a maximum diameter of approximately 4 cm. After consultation with the department of cardiac macrovascular surgery, the patient was diagnosed with left CAA with aneurysm formation and an anomalous RSCA and LVA and was transferred to that department. The patient underwent AA aneurysm resection and artificial blood vessel replacement under general anesthesia and cardiopulmonary bypass. No abnormality was found during the 2-mo follow-up after discharge. CONCLUSION: A CAA is a rare congenital anomaly of vascular development. The present unique case of CAA with aneurysm formation and an anomalous RSCA and LVA enriches existing CAA data.
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Although the increasing trend of sensor signal with decreasing oxygen partial pressure was observed quite early, the underlying mechanism is still elusive, which is a hindrance to accurate gas detection under varying oxygen partial pressure. In this work, a sensing model based on previous experimental and theoretical results is proposed, in which the O2- species is determined to be the main oxygen species because O- species has not been observed by direct spectroscopic studies. On this basis, combined with the band bending of SnO2 at different oxygen partial pressures, the functional relationship between the surface electron concentration, oxygen partial pressure, and reducing gas concentration is established, which includes three forms corresponding to the depletion layer, accumulation layer, and flat band. In the depletion layer case, the variation of the sensor resistance to different concentrations of CO and oxygen can be well fitted with our function model. Besides, this model predicts that the response of sensors will no longer maintain the increasing trend in an extremely hypoxic atmosphere but will decrease and approach 1 with the background oxygen content further going down to 0.
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Elétrons , Oxigênio , Pressão ParcialRESUMO
BACKGROUND: Hepatocellular carcinoma (HCC) is the sixth most common cancer in the world and the third leading cause of cancer-related death. Although the diagnostic scheme of HCC is currently undergoing refinement, the prognosis of HCC is still not satisfactory. In addition to certain factors, such as tumor size and number and vascular invasion displayed on traditional imaging, some histopathological features and gene expression parameters are also important for the prognosis of HCC patients. However, most parameters are based on postoperative pathological examinations, which cannot help with preoperative decision-making. As a new field, radiomics extracts high-throughput imaging data from different types of images to build models and predict clinical outcomes noninvasively before surgery, rendering it a powerful aid for making personalized treatment decisions preoperatively. OBJECTIVE: This study reviewed the workflow of radiomics and the research progress on magnetic resonance imaging (MRI) radiomics in the diagnosis and treatment of HCC. METHODS: A literature review was conducted by searching PubMed for search of relevant peer-reviewed articles published from May 2017 to June 2021.The search keywords included HCC, MRI, radiomics, deep learning, artificial intelligence, machine learning, neural network, texture analysis, diagnosis, histopathology, microvascular invasion, surgical resection, radiofrequency, recurrence, relapse, transarterial chemoembolization, targeted therapy, immunotherapy, therapeutic response, and prognosis. RESULTS: Radiomics features on MRI can be used as biomarkers to determine the differential diagnosis, histological grade, microvascular invasion status, gene expression status, local and systemic therapeutic responses, and prognosis of HCC patients. CONCLUSION: Radiomics is a promising new imaging method. MRI radiomics has high application value in the diagnosis and treatment of HCC.
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This is a retrospective study to analyze the efficacy of uterine artery chemoembolization (UACE) combined with ultrasound-guided curettage in the treatment of cervical pregnancy and the factors affecting the postoperative outcome. A total of 26 subjects were included in the study and were divided into a control group of 12 and an observer group of 14, all patients with cervical pregnancy diagnosed in our hospital from January 2016 to January 2020. Patients in the control group were treated with methotrexate injection (MTX) combined with ultrasound-guided curettage in our hospital, while the observer group was treated with UACE combined with ultrasound-guided curettage. The efficacy of the two groups was evaluated at 3 months postoperatively, and data on patients' age, days of menopause, pregnancy frequency, and vaginal bleeding were collected retrospectively. Intraoperative bleeding, time to recovery of serum human chorionic gonadotropin (HCG), hospitalization time, time to return to normal menstruation, time to disappearance of gestational sac, pregnancy frequency, presence of endometrial inflammation, gestational week, maximum diameter of gestational sac, thinnest myometrium, endogenous-exogenous type, gestational sac size, and HCG level were recorded in both groups. Single-factor analysis and multifactor logistic regression models were used to analyze the factors influencing the surgical outcomes of patients. The results of the study showed that the overall efficiency of the observer group was significantly higher than that of the control group, while intraoperative bleeding, hospital stay, time to return to normal menstruation, and time to disappearance of the gestational sac were all lower than those of the control group (p < 0.05). The results of univariate and multifactorial analyses showed that endometrial inflammation, gestational week, maximum diameter of the gestational sac, thinnest myometrium, and endogenous-exogenous type could affect the patients' postoperative recovery (p < 0.05); gestational week, maximum diameter of the gestational sac, and thinnest myometrium were independent factors affecting the patients' postoperative recovery (p < 0.05). The above results suggest that UACE combined with ultrasound-guided uterine clearance for cervical pregnancy can significantly improve treatment efficacy, reduce intraoperative bleeding, and improve recovery time from postoperative related symptoms. The treatment efficacy of patients with cervical pregnancy was related to the gestational week, the maximum diameter of the gestational sac, and the thinnest muscle layer.
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The present study aimed to investigate the value of intravoxel incoherent motion diffusion weighted imaging (IVIM-DWI) in the preoperative prediction of the histologic differentiation of hepatocellular carcinoma (HCC). Seventy HCC patients were scanned with a 3.0 T magnetic resonance scanner. The values of apparent diffusion coefficient (ADC), slow apparent diffusion coefficient (D), fast apparent diffusion coefficient (D*), and the fraction of the fast apparent diffusion coefficient (f) were measured. Analysis of variance was used to compare the differences in parameters between groups with different degrees of histologic differentiation. p < 0.05 was considered statistically significant. Receiver operating characteristic (ROC) curves were used to analyse the efficacy of IVIM-DWI parameters for predicting the histologic differentiation of HCC. The ADC and D values for well, moderately and poorly differentiated HCC were 1.35 ± 0.17 × 10-3 mm2/s, 1.16 ± 0.17 × 10-3 mm2/s, 0.98 ± 0.21 × 10-3 mm2/s, and 1.06 ± 0.15 × 10-3 mm2/s, 0.88 ± 0.16 × 10-3 mm2/s, 0.76 ± 0.18 × 10-3 mm2/s, respectively, and all differences were significant. The D* and f values of the three groups were 32.87 ± 14.70 × 10-3 mm2/s, 41.68 ± 17.90 × 10-3 mm2/s, 34.54 ± 18.60 × 10-3 mm2/s and 0.22 ± 0.07, 0.23 ± 0.08, 0.18 ± 0.07, respectively, with no significant difference. When the cut-off values of ADC and D were 1.25 × 10-3 mm2/s and 0.97 × 10-3 mm2/s, respectively, their diagnostic sensitivities and specificities for distinguishing well differentiated HCC from moderately differentiated and poorly differentiated HCC were 73.3%, 85.5%, 86.7%, and 78.2%, and their areas under the ROC curve were 0.821 and 0.841, respectively. ADC and D values can be used preoperatively to predict the degree of histologic differentiation in HCC, and the D value has better diagnostic value.
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Carcinoma Hepatocelular/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Interpretação de Imagem Assistida por Computador , Neoplasias Hepáticas/diagnóstico por imagem , Adulto , Idoso , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Movimento (Física)RESUMO
BACKGROUND: Bone metastasis is one of the most common complications of Prostate Cancer (PCa). The detection of distal bone metastasis at the time of initial PCa diagnosis is valuable for the determination of therapeutic methods and for the prognosis of PCa. Many current therapeutic methods target PCa bone metastasis, but no uniform evaluation standard for therapeutic efficacy has been established; in addition, traditional therapeutic evaluation standards that rely on changes in the measured tumor volume are quite controversial. In clinical practice, the volumes of some tumors often change nonsignificantly at the early stage of therapy (especially targeted therapy), while the volumes of other tumors, such as metastatic bone lesions, are difficult to measure. Diffusion-Weighted Imaging (DWI) not only reflects the diffusion characteristics of tissues but can also allow the analysis of microstructural and functional changes in tissues. Therefore, DWI is suitable for evaluations of early responses to tumor therapy. OBJECTIVE: This study mainly reviews the principle of DWI and its progress in the detection and therapy evaluation of PCa bone metastasis. METHODS: PubMed was searched to identify eligible articles up to December 26, 2020. The keywords of the analysis included DWI, PCa, bone metastasis, therapeutic response, targeted therapy, Bone Scintigraphy (BS), Positron Emission Tomography/Computed Tomography (PET/CT) and metastatic Castration-Resistant Prostate Cancer (mCRPC). RESULTS: This review based on collected articles achieved an imaging biomarker for detection and therapy evaluation of PCa bone metastasis. CONCLUSION: DWI is a promising imaging method for the detection and therapeutic evaluation of PCa bone metastases.
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Antineoplásicos/uso terapêutico , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/tratamento farmacológico , Imagem de Difusão por Ressonância Magnética , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/tratamento farmacológico , Neoplasias Ósseas/secundário , Humanos , MasculinoRESUMO
The incidence of vascular cognitive impairment (VCI) has been increasing for years and has become a major disabling factor in middle-aged and elderly populations. The pathogenesis of VCI is unclear, and there are no standard diagnostic criteria. Resting-state functional magnetic resonance imaging (rs-fMRI) can be used to detect spontaneous brain functional activity in a resting state, which facilitates in-depth investigation of the pathogenesis of VCI and provides an objective reference for early diagnosis, differential diagnosis, and prognostic evaluation. This article mainly reviews the principle and analysis of rs-fMRI data, as well as the progress of its application for VCI diagnosis.
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Traditional magnetic resonance (MR) diffusion-weighted imaging (DWI) uses a single exponential model to obtain the apparent diffusion coefficient to quantitatively reflect the diffusion motion of water molecules in living tissues, but it is affected by blood perfusion. Intravoxel incoherent motion (IVIM)-DWI utilizes a double-exponential model to obtain information on pure water molecule diffusion and microcirculatory perfusion-related diffusion, which compensates for the insufficiency of traditional DWI. In recent years, research on the application of IVIM-DWI in the diagnosis and treatment of hepatic diseases has gradually increased and has achieved considerable progress. This study mainly reviews the basic principles of IVIM-DWI and related research progress in the diagnosis and treatment of hepatic diseases.
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The present study aimed to explore the value of intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) in differentiating hepatocellular carcinoma (HCC) from intrahepatic cholangiocarcinoma (ICC). This study included 65 patients with malignant hepatic nodules (55 with HCC, 10 with ICC), and 17 control patients with normal livers. All patients underwent IVIM-DWI scans on a 3.0 T magnetic resonance imaging (MRI) scanner. The standard apparent diffusion coefficient (ADC), pure diffusion coefficient (Dslow), pseudo-diffusion coefficient (Dfast), and perfusion fraction (f) were obtained. Differences in the parameters among the groups were analysed using one-way ANOVA, with p < 0.05 indicating statistical significance. Receiver operating characteristic (ROC) curve analysis was used to compare the efficacy of each parameter in differentiating HCC from ICC. ADC, Dslow, Dfast, f significantly differed among the three groups. ADC and Dslow were significantly lower in the HCC group than in the ICC group, while Dfast was significantly higher in the HCC group than in the ICC group; f did not significantly differ between the HCC and ICC groups. When the cut-off values of ADC, Dslow, and Dfast were 1.27 × 10-3 mm2/s, 0.81 × 10-3 mm2/s, and 26.04 × 10-3 mm2/s, respectively, their diagnostic sensitivities for differentiating HCC from ICC were 98.18%, 58.18%, and 94.55%, their diagnostic specificities were 50.00%, 80.00%, and 80.00%, and their areas under the ROC curve (AUCs) were 0.687, 0.721, and 0.896, respectively. Dfast displayed the largest AUC value. IVIM-DWI can be used to differentiate HCC from ICC.
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Carcinoma Hepatocelular/diagnóstico , Colangiocarcinoma/diagnóstico , Imagem de Difusão por Ressonância Magnética , Neoplasias Hepáticas/diagnóstico , Adolescente , Adulto , Idoso , Ductos Biliares Intra-Hepáticos/diagnóstico por imagem , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Colangiocarcinoma/diagnóstico por imagem , Colangiocarcinoma/patologia , Diagnóstico Diferencial , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Fígado/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
The prosperous development of stretchable electronics poses a great demand on stretchable conductive materials that could maintain their electrical conductivity under tensile strain. Previously reported strategies to obtain stretchable conductors usually involve complex structure-fabricating processes or utilization of high-cost nanomaterials. It remains a great challenge to produce stretchable and conductive materials via a scalable and cost-effective process. Herein, a large-scalable pyrolysis strategy is developed for the fabrication of intrinsically stretchable and conductive textile in utilizing low-cost and mass-produced weft-knitted textiles as raw materials. Due to the intrinsic stretchability of the weft-knitted structure and the excellent mechanical and electrical properties of the as-obtained carbonized fibers, the obtained flexible and durable textile could sustain tensile strains up to 125% while keeping a stable electrical conductivity (as shown by a Modal-based textile), thus ensuring its applications in elastic electronics. For demonstration purposes, stretchable supercapacitors and wearable thermal-therapy devices that showed stable performance with the loading of tensile strains have been fabricated. Considering the simplicity and large scalability of the process, the low-cost and mass production of the raw materials, and the superior performances of the as-obtained elastic and conductive textile, this strategy would contribute to the development and industrial production of wearable electronics.
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Phycoerythrins (PE) in phycobilisomes from Polysiphonia urceolata were studied in this research. Dissociative products of phycobilisomes were analyzed by sucrose density gradient centrifugation and native-PAGE. At least three types of PEs were found in the dissociative products of phycobilisomes. According to their molecular weights, absorption spectra and subunit components, they should be PE hexamer containing γ1 subunit, PE hexamer containing γ2 subunit and PE monomer containing no γ subunit. PEs bigger than hexmer were also found in the dissociative products of phycobilisomes in 200mM phosphate buffer when dissociated phycobilisomes were analyzed by sucrose density gradient centrifugation. PE trimers containing no γ subunits were also found in products of dissociated phycobilisomes in deionized water when dissociated phycobilisomes were analyzed by native-PAGE. This is the first time that pure PE hexamers containing γ2 subunits were isolated from P. urceolata. The PE monomers containing no γ subunits should come from PE trimers or hexamers containing no γ subunits in the "rod" of phycobilisomes. It can be concluded that there are three types of PEs in "rod" of phycobilisomes from P. urceolata: PE containing γ1 subunit, PE containing γ2 subunit and PE containing no γ subunit.
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Ficoeritrina/química , Rodófitas/química , Ficobiliproteínas/química , Ficobiliproteínas/isolamento & purificação , Ficobilissomas/química , Ficoeritrina/isolamento & purificaçãoRESUMO
Three buffer systems of Imidazole-Acetic acid, HEPES-Imidazole/Bis-tris and Bis-tris-HEPES-MES were designed based on the principle of discontinuous polyacrylamide gel electrophoresis (PAGE) for the native PAGE which could be performed in pH 7.0 and 6.5 in order to analyze and prepare the minor components of allophycocyanin (AP) and R-phycocyanin (R-PC) from marine red macroalga Polysiphonia urceolata. These AP and R-PC phycobiliproteins are easily denatured in alkaline environments. The obtained results demonstrated that the PAGE modes performed in the buffer systems of HEPES-Imidazole/Bis-tris and Bis-tris-HEPES-MES gave the satisfactory resolution and separation of AP and R-PC proteins. The absorption and fluorescence spectra of the AP and R-PC proteins which were prepared by the established PAGE modes proved that they maintained natural spectroscopic characteristics. The established PAGE modes may also provide useful references and selections for some other proteins that are sensitive to alkaline environments or are not effectively separated by the classical PAGE modes performed normally in alkaline buffer systems.