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1.
EBioMedicine ; 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31767539

RESUMO

BACKGROUND: Identification of pregnancies with postpartum haemorrhage (PPH) antenatally rather than intrapartum would aid delivery planning, facilitate transfusion requirements and decrease maternal complications. MRI has been increasingly used for placenta evaluation. Here, we aim to build a nomogram incorporating both clinical and radiomic features of placenta to predict the risk for PPH in pregnancies during caesarian delivery (CD). METHODS: A total of 298 pregnant women were retrospectively enrolled from Henan Provincial People's Hospital (training cohort: n = 207) and from The Third Affiliated Hospital of Zhengzhou University (external validation cohort: n = 91). These women were suspected with placenta accreta spectrum (PAS) disorders and underwent MRI for placenta evaluation. All of them underwent CD and were singleton. PPH was defined as more than 1000 mL estimated blood loss (EBL) during CD. Radiomic features were selected based on their correlations with EBL. Radiomic, clinical, radiological, clinicoradiological and clinicoradiomic models were built to predict the risk of PPH for each patient. The model with the best prediction performance was validated with its discrimination ability, calibration curve and clinical application. FINDINGS: Thirty-five radiomic features showed strong correlation with EBL. The clinicoradiomic model resulted in the best discrimination ability for risk prediction of PPH, with AUC of 0.888 (95% CI, 0.844-0.933) and 0.832 (95% CI, 0.746-0.913), sensitivity of 91.2% (95% CI, 85.8%-96.7%) and 97.6% (95% CI, 92.7%-100%) in the training and validation cohort respectively. For patients with severe PPH (EBL more than 2000 mL), 53 out of 55 pregnancies (96.4%) in the training cohort and 18 out of 18 (100%) pregnancies in the validation cohort were identified by the clinicoradiomic model. The model performed better in patients without placenta previa (PP) than in patients with PP, with AUC of 0.983 compared with 0.867, sensitivity of 100% compared with 90.8% in the training cohort, AUC of 0.832 compared with 0.815, sensitivity of 97.6% compared with 97.2% in the validation cohort. INTERPRETATION: The clinicoradiomic model incorporating both prenatal clinical factors and radiomic signature of placenta on T2WI showed good performance for risk prediction of PPH. The predictive model can identify severe PPH with high sensitivity and can be applied in patients with and without PP.

2.
Eur J Radiol ; 121: 108711, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31677544

RESUMO

PURPOSE: We developed and validated a radiomic model based on mammography and assessed its value for predicting the pathological diagnosis of Breast Imaging Reporting and Data System (BI-RADS) category 4 calcifications. MATERIALS AND METHODS: Patients with a total of 212 eligible calcifications were recruited (159 cases in the primary cohort and 53 cases in the validation cohort). In total, 8286 radiomic features were extracted from the craniocaudal (CC) and mediolateral oblique (MLO) images. Machine learning was used to select features and build a radiomic signature. The clinical risk factors were selected from the independent clinical factors through logistic regression analyses. The radiomic nomogram incorporated the radiomic signature and an independent clinical risk factor. The diagnostic performance of the radiomic model and the radiologists' empirical prediction model was evaluated by the area under the receiver operating characteristic curve (AUC). The differences between the various AUCs were compared with DeLong's test. RESULTS: Six radiomic features and the menopausal state were included in the radiomic nomogram, which discriminated benign calcifications from malignant calcifications with an AUC of 0.80 in the validation cohort. The difference between the classification results of the radiomic nomogram and that of radiologists was significant (p < 0.05). Particularly for patients with calcifications that are negative on ultrasounds but can be detected by mammography (MG+/US- calcifications), the identification ability of the radiomic nomogram was very strong. CONCLUSIONS: The mammography-based radiomic nomogram is a potential tool to distinguish benign calcifications from malignant calcifications.

3.
Radiother Oncol ; 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31668985

RESUMO

BACKGROUND AND PURPOSE: We used radiomic analysis to establish a radiomic signature based on anatomical magnetic resonance imaging (MRI) sequences and explore its effectiveness as a novel prognostic biomarker for skull base chordoma (SBC). MATERIALS AND METHODS: In this retrospective study, radiomic analysis was performed using preoperative axial T1 FLAIR, T2-weighted, and enhanced T1 FLAIR from a single hospital. The primary clinical endpoint was progression-free survival. A total of 1860 3-D radiomic features were extracted from manually segmented region of interest. Pearson correlation coefficient was used for feature dimensional reduction and a ridge regression-based Cox proportional hazards model was used to determine a radiomic signature. Afterwards, radiomic signature and nine other potential prognostic factors, including age, gender, histological subtype, dural invasion, blood supply, adjuvant radiotherapy, extent of resection, preoperative KPS, and postoperative KPS were analyzed to build a radiomic nomogram and a clinical model. Finally, we compared the nomogram with each prognostic factor/model by DeLong's test. RESULTS: A total of 148 SBC patients were enrolled, including 64 with disease progression. The median follow-up time was 52 months (range 4-122 months). The Harrell's concordance index of the radiomic signature was 0.745 (95% CI, 0.709-0.781) for the validation cohort, and its discrimination accuracy in predicting progression risk at 5 years in the same cohort was 82.4% (95% CI, 72.6-89.7%). CONCLUSIONS: The radiomics is a low-cost, non-invasive method to predict SBC prognosis preoperatively. Radiomic signature is a potential prognostic biomarker that may allow the individualized evaluation of patients with SBC.

4.
Curr Drug Targets ; 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31670620

RESUMO

AIMS: This study provided an overview of several emerging anti-diabetic molecules. BACKGROUND: Diabetes is a complex metabolic disorder involving dysregulation of glucose homeostasis at various levels. Insulin, which is produced by ß-pancreatic cells, is a chief orchestrator of glucose metabolism, regulating its consumption within cells, which leads to energy generation or storage as glycogen. Abnormally lower insulin secretion from ß-cells, insulin insensitivity, and insulin tolerance lead to higher plasma glucose levels, resulting in metabolic complications. The last century has witnessed extraordinary efforts by the scientific community to develop anti-diabetic drugs, and these efforts yielded the discovery of exogenous insulin and various classes of oral anti-diabetic drugs. OBJECTIVE: Despite these exhaustive anti-diabetic pharmaceutical and therapeutic efforts, long-term glycemic control, hypoglycemic crisis, safety issues, large-scale economic burden, side effects remain core problems. METHOD: The last decade has witnessed the development of various new classes of anti-diabetic drugs with different pharmacokinetic and pharmacodynamics profiles. Details of their FDA approvals and advantages/disadvantages are summarized in this review, Result: Salient features of insulin degludec, sodium glucose co-transporter 2 inhibitors, glucokinase activators, fibroblast growth factor 21 receptor agonists, and GLP-1 agonists are discussed. CONCLUSION: In the future, these new anti-diabetic drugs should have broad clinical applicability.

5.
Epilepsia ; 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31769021

RESUMO

OBJECTIVE: Temporal lobe epilepsy is a common form of epilepsy that might be amenable to surgery. However, magnetic resonance imaging (MRI)-negative hippocampal sclerosis (HS) can hamper early diagnosis and surgical intervention for patients in clinical practice, resulting in disease progression. Our aim was to automatically detect and evaluate the structural alterations of HS. METHODS: Eighty patients with pharmacoresistant epilepsy and histologically proven HS and 80 healthy controls were included in the study. Two automated classifiers relying on clinically empirical and radiomics features were developed to detect HS. Cross-validation was implemented on all participants, and specificity was assessed in the 80 controls. The performance, robustness, and clinical utility of the model were also evaluated. Structural analysis was performed to investigate the morphological abnormalities of HS. RESULTS: The computational model based on clinical empirical features showed excellent performance, with an area under the curve (AUC) of 0.981 in the primary cohort and 0.993 in the validation cohort. One of the features, gray-white matter boundary blurring in the temporal pole, exhibited the highest weight in model performance. Another model based on radiomics features also showed satisfactory performance, with AUC of 0.997 in the primary cohort and 0.978 in the validation cohort. In particular, the model improved the detection rate of MRI-negative HS to 96.0%. The novel feature of cortical folding complexity of the temporal pole not only played a crucial role in the classifier but also had significant correlation with disease duration. SIGNIFICANCE: Machine learning with quantitative clinical and radiomics features is shown to improve HS detection. HS-related structural alterations were similar in the MRI-positive and MRI-negative HS patient groups, indicating that misdiagnosis originates mainly from empirical interpretation. The cortical folding complexity of the temporal pole is a potentially valuable feature for exploring the nature of HS.

6.
Bioelectrochemistry ; 131: 107396, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31704455

RESUMO

We report a novel chiral interface based on polysaccharides that was integrated via an amidation reaction between the COOH of sodium alginate and the NH2 of chitosan to form a chiral selector (SA-CS) with three dimensional N-doped graphene-CNT (NGC) as the substrate material. This interface was used for chiral discrimination of tryptophan (Trp) enantiomers via electrochemical measurements. The FT-IR, SEM, TEM and XPS characterization showed that the chiral selector and substrate materials were prepared successfully. Compared with individual SA-CS and NGC, the integrated polysaccharides/3D NGC showed higher enantioselectivity for L-Trp than D-Trp due to the smaller steric hindrance for D-Trp during the formation of three-point interactions between the two diastereoisomeric enantiomer-selector complexes, which allowed L-Trp to more easily detach from the electrode modification layer and approach the electrode surface, facilitating its approach and confirming that SA-CS had a higher constant for L-Trp when applied to real samples.

7.
ACS Nano ; 13(10): 12127-12136, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31566944

RESUMO

Organic-inorganic hybrid perovskites (OHPs) have garnered much attention among the photovoltaic and light-emitting diode research community due to their excellent optoelectronic properties and low-cost fabrication. Defects in perovskites have been proposed to affect device efficiency and stability and to have a potential role in enabling ion migration. In this study, the dynamic behavior and electronic properties of intrinsic defects in CH3NH3PbBr3 (MAPbBr3) were explored at the atomic scale. We use scanning tunneling microscopy to show unambiguously the occurrence of vacancy-assisted transport of individual ions as well as the existence of vacancy defect clusters at the OHP surface. We combine these observations with density functional theory (DFT) calculations to identify the mechanisms for this ion motion and show that ion transport energy barriers, as well as transport mechanisms, at the surface depend on crystal direction. DFT calculations also reveal that vacancy defect clusters can significantly modify the local work function of the perovskite surface, which is then expected to alter interfacial charge transport in a device. Our work provides a microscopic insight into the mechanism of ion migration in OHPs and also delivers the useful information for device improvement from the perspective of interface engineering.

8.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(10): 1049-1054, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31642443

RESUMO

OBJECTIVE: To study the changes and significance of apoptosis signal-regulating kinase 1 (ASK1) in left ventricular remodeling in FVB/N mice. METHODS: A total of 54 FVB/N mice were randomly divided into 4 groups: 0 d group with 8 mice, 7 d group with 10 mice, 14 d group with 16 mice, and 21 d group with 20 mice. A model of cardiac remodeling was established by intraperitoneal injection of isoproterenol (ISO) at a daily dose of 30 mg/kg, and the 7 d, 14 d, and 21 d groups were injected for 7, 14, and 21 consecutive days respectively. The 0 d group was given intraperitoneal injection of an equal volume of normal saline. Echocardiography was used to measure left ventricular posterior wall thickness at end diastole (dLVPW) and the ratio of heart weight to tibia length (HW/TL) was measured. Hematoxylin-eosin staining was used to measure left ventricular myocardial fiber diameter. Picric-Sirius red staining was used to measure myocardial collagen deposition area in the left ventricle. Quantitative real-time PCR was used to measure the mRNA expression of ASK1, type I collagen (collagen I), and B-type natriuretic peptide (BNP). The mortality rate was observed for each group. RESULTS: There were gradual increases in HW/TL, myocardial fiber diameter, and dLVPW after 0, 7, and 14 days of ISO injection (P<0.05). There were no significant changes in HW/TL ratio and dLVPW from days 14 to 21 of ISO injection (P>0.05), while there was a significant reduction in myocardial fiber diameter (P<0.05), which was similar to the value on day 7 (P>0.05). There were significant increases in myocardial collagen deposition area and the mRNA expression of collagen I, ASK1, and BNP after 0, 7, 14, and 21 days of ISO injection, which reached the peaks on day 21 (P<0.01). The mRNA expression of ASK1 was positively correlated with myocardial collagen deposition area and the mRNA expression of collagen I and BNP and had a weak correlation with HW/TL, myocardial fiber diameter, and dLVPW. There was a significant increase in the mortality rate of the mice over the time of ISO injection. CONCLUSIONS: The expression of ASK1 in the myocardium is closely associated with left ventricular remodeling. The increase of ASK1 expression may lead to the aggravation of left ventricular remodeling, and the mechanism of which needs further study.


Assuntos
Remodelação Ventricular , Animais , Isoproterenol , MAP Quinase Quinase Quinase 5 , Camundongos , Miocárdio , Miócitos Cardíacos
9.
Sensors (Basel) ; 19(20)2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31652626

RESUMO

In the indoor location field, the quality of received-signal-strength-indicator (RSSI) fingerprints plays a key role in the performance of indoor location services. However, changes in an indoor environment may lead to the decline of location accuracy. This paper presents a localization method employing a Hybrid Wireless fingerprint (HW-fingerprint) based on a convolutional neural network (CNN). In the proposed scheme, the Ratio fingerprint was constructed by calculating the ratio of different RSSIs from important contribution access points (APs). The HW-fingerprint combined the Ratio fingerprint and the RSSI to enhance the expression of indoor environment characteristics. Moreover, a CNN architecture was constructed to learn important features from the complex HW-fingerprint for indoor locations. In the experiment, the HW-fingerprint was tested in an actual indoor scene for 15 days. Results showed that the average daily location accuracy of the K-Nearest Neighbor (KNN), Support Vector Machines (SVMs), and CNN was improved by 3.39%, 8.03% and 9.03%, respectively, when using the HW-fingerprint. In addition, the deep-learning method was 4.19% and 16.37% higher than SVM and KNN in average daily location accuracy, respectively.

10.
Acta Histochem ; : 151455, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31587886

RESUMO

As the the major functional component of Paeonia suffruticosa, paeonol (PAE) has shown its potential to inhibit the progression of multiple cancer types. In the current study, the mechanism driving the effect of PAE on osteosarcoma (OS) was investigated by focusing on its influence on TLR4-mediated MAPK/NF-κB pathway. Human OS cells were firstly administrated with PAE of different concentrations to assess its effect on the proliferation, apoptosis, metastasis, and TLR4/MAPK/NF-κB pathway in OS cells. Thereafter, the level of TLR4 was induced in OS cells before PAE administration to explore the role of the molecule in the anti-OS function of PAE. The results of in vitro assays were further validated with xenograft mice models. The administration of PAE of two doses both suppressed the proliferation and induced apoptosis in OS cells in a dose-dependent manner. Regarding the effect on the metastasis potential of OS cells, PAE inhibited the migration and invasion potential of the cells, but the effect did not change with concentrations. The administration of PAE also inhibited the expression of TLR4 and deactivated MAPK/NF-κB pathway. Moreover, the induced expression of TLR4 counteracted the anti-OS function of PAE. Further validation with xenograft models also showed that PAE inhibited solid tumor growth and TLR4 expression in OS mice. In conclusion, it was inferred that the anti-OS function of PAE depended on the inhibition of TLR4 and its downstream MAPK/NF-κB pathway.

11.
Int J Mol Sci ; 20(20)2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31627272

RESUMO

Aberrant expression of programmed death ligand 1 (PD-L1) on tumor cells impedes antitumor immunity and instigates immune evasion. The remarkable efficacy of immune checkpoint blockade has been confirmed in various solid tumors. However, the correlation between PD-L1 expression and host immunological landscape remains of considerable controversy in non-small cell lung cancer (NSCLC). In the present study, PD-L1 expression and CD8+ tumor-infiltrating lymphocyte (TIL) infiltration levels were determined by immunohistochemistry (IHC) in tumor sections of 138 NSCLC patients. The expression level of PD-L1 was positively correlated with the abundance of CD8 + TILs (p < 0.0001). Furthermore, no constitutive expression of PD-L1 was observed in the majority of six NSCLC cell lines detected by Western blot; but exposure to interferon-γ (IFN-γ), a primary cytokine secreted by activated CD8+ T cells, prominently increased PD-L1 expression. Notably, a significantly positive association was determined within PD-L1, CD8 and IFN-γ gene expression by qRT-PCR, which was corroborated by RNA-sequencing from TCGA lung cancer dataset. These findings demonstrate that PD-L1 expression indicates an adaptive immune resistance mechanism adopted by tumor cells in the aversion of immunogenic destruction by CD8+ TILs. Both higher expression of PD-L1 and infiltration of CD8+ TILs were correlated with superior prognosis (p = 0.044 for PD-L1; p = 0.002 for CD8). Moreover, Cox multivariate regression analysis showed that the combination of PD-L1 and CD8 were independent prognostic factors, which was more accurate in prediction of prognosis in NSCLC than individually. Finally, we found that IFN-γ induced the upregulation of PD-L1 in NSCLC cells, mainly through the JAK/STAT1 signaling pathway. In conclusion, PD-L1 expression is mainly induced by activated CD8+ TILs via IFN-γ in the immune milieu and indicates pre-existing adaptive immune response in NSCLC.

12.
Eur J Radiol ; 121: 108647, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31561943

RESUMO

PURPOSE: The preoperative prediction of treatment response is important for determining individual treatment strategies for invasive functional pituitary adenoma (IFPA). This study aimed to develop and validate a magnetic resonance imaging (MRI)-based radiomic signature for preoperative prediction of treatment response in IFPA. METHOD: One hundred and sixty-three patients with IFPA were enrolled and divided into primary (n = 108) and validation cohorts (n = 55) according to time point. IFPA patients were divided into remission and non-remission according to postoperative hormone levels. Radiomic features were extracted from their MR images and a radiomic signature was built using a support vector machine. Subsequently, multivariable logistic regression analysis was used to select the most informative clinical features, and a radiomic model incorporating the radiomic signature and selected clinical features was constructed and used as the final predictive model. RESULTS: Seven radiomic features were selected to construct the radiomic signature, which achieved an area under the curve (AUC) of 0.834 and 0.808 on the primary and validation cohorts respectively. The radiomic model incorporating the radiomic signature and Knosp grade showed good discrimination abilities and calibration, with AUCs of 0.832 and 0.811 for the primary and validation cohorts respectively. The radiomic signature and radiomic model better estimated the treatment responses of patients with IFPA than our clinical features model. Decision curve analysis showed the radiomic model was clinically useful. CONCLUSIONS: This radiomic model may help neurosurgeons predict the treatment responses of patients with IFPA before surgery and determine individual treatment strategies.

13.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 33(10): 1265-1269, 2019 Oct 15.
Artigo em Chinês | MEDLINE | ID: mdl-31544437

RESUMO

Objective: To analyze the effectiveness of fast track protocol of geriatric intertrochanteric fracture on operative waiting time, operation time, perioperative blood loss, providing data support for clinical therapy. Methods: The clinical data of 240 elderly patients with intertrochanteric fracture admitted between January 2015 and December 2018 were retrospectively analyzed. They were divided into traditional protocol group (148 cases, group A) and fast track group (92 cases, group B). All patients were treated with closed reduction intramedullary nail (proximal femoral nail antirotation) surgery. There was no significant difference in gender, age, sides, fracture classification, fracture type, complications, the proportion of patients with more than 3 kinds of medical diseases, and the time from injury to admission between the two groups ( P>0.05). Analysis index included operative waiting time (hospitalization to operation time), operation time, percentage of operation performing in 48 and 72 hours, percentage of transfusion, changes of hematocrit (Hct) at different stage (admission, operation day, and postoperative 1, 3 days), blood loss by fracture and cephalomedullary nail, intraoperative dominant blood loss, total blood loss in perioperative period were recorded and compared. Results: The operative waiting time, operation time, Hct on operation day and postoperative 3 days, blood loss by fracture, transfusion volume, and total blood loss in perioperative period in group B were significantly less than those in group A ( P<0.05), and the percentage of operation performing in 48 and 72 hours in group B were significantly higher than those in group A ( P<0.05). There was no signifcant difference in Hct on admission and postoperative 1 day, intraoperative dominant blood loss, percentage of transfusion, blood loss by cephalomedullary nail between the two groups ( P>0.05). Conclusion: Fast track can shorten the operative waiting time of geriatric intertrochanteric fracture, reduce the blood loss by fracture, total blood loss in perioperative period, and transfusion volume. Early operation is conducive to improve the anemia status of patients during perioperative period.


Assuntos
Fixação Intramedular de Fraturas , Fraturas do Quadril , Idoso , Perda Sanguínea Cirúrgica , Pinos Ortopédicos , Humanos , Duração da Cirurgia , Estudos Retrospectivos
14.
Nat Commun ; 10(1): 4011, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31488814

RESUMO

Ammonia represents a promising liquid fuel for hydrogen storage, but its large-scale application is limited by the need for precious metal ruthenium (Ru) as catalyst. Here we report on highly efficient ammonia decomposition using novel high-entropy alloy (HEA) catalysts made of earth abundant elements. Quinary CoMoFeNiCu nanoparticles are synthesized in a single solid-solution phase with robust control over the Co/Mo atomic ratio, including those ratios considered to be immiscible according to the Co-Mo bimetallic phase diagram. These HEA nanoparticles demonstrate substantially enhanced catalytic activity and stability for ammonia decomposition, with improvement factors achieving >20 versus Ru catalysts. Catalytic activity of HEA nanoparticles is robustly tunable by varying the Co/Mo ratio, allowing for the optimization of surface property to maximize the reactivity under different reaction conditions. Our work highlights the great potential of HEAs for catalyzing chemical transformation and energy conversion reactions.

15.
Sci Rep ; 9(1): 12748, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31485009

RESUMO

Here, we propose the concept of an "optical vacuum cleaner" for optomechanical manipulation of nanoparticles. We utilize a dielectric cuboid to generate an optical gradient force exerted on the nanoparticles for particle's hovering and trapping. We show that the permittivity contrast between the particle and the nanohole leads to the deep subwavelength light confinement and enhancement at the opening of the nanohole located at the shadow surface of the particle. The proposed "optical vacuum cleaner" can be utilized in optomechanical manipulations on particles such as noble metal nanoparticles adsorbed on surfaces or controlling the particles taking part in cellular uptake.

16.
Eur J Radiol ; 118: 81-87, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31439263

RESUMO

PURPOSE: Patients with skull base chordoma and chondrosarcoma have different prognoses and are not readily differentiated preoperatively on imaging. Multiparametric magnetic resonance imaging (MRI) is a routine diagnostic tool that can noninvasively characterize the salient characteristics of tumors. In the present study, we developed and validated a preoperative multiparametric MRI-based radiomic signature for differentiating these tumors. METHOD: This retrospective study enrolled 210 patients and consecutively divided them into the primary and validation cohorts. A total of 1941 radiomic features were acquired from preoperative T1-weighted imaging, T2-weighted imaging and contrast-enhanced T1-weighted imaging for each patient. The most discriminative features were selected by minimum-redundancy maximum-relevancy and recursive feature elimination algorithms in the primary cohort. The multiparametric and single-sequence MRI signatures were constructed with the selected features using a support vector machine model in the primary cohort. The ability of the novel radiomic signatures to differentiate chordoma from chondrosarcoma were assessed using receiver operating characteristic curve analysis in the validation cohort. RESULTS: The multiparametric radiomic signature, which consisted of 11 selected features, reached an area under the receiver operating characteristic curve of 0.9745 and 0.8720 in the primary and validation cohorts, respectively. Moreover, compared with each single-sequence MRI signature, the multiparametric radiomic signature exhibited better classification performance with significant improvement (p <  0.05, Delong's test) in the primary cohorts. CONCLUSION: By combining features from three MRI sequences, the multiparametric radiomics signature can accurately and robustly differentiate skull base chordoma from chondrosarcoma.

17.
Clin Transl Gastroenterol ; 10(8): e00070, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31373932

RESUMO

OBJECTIVES: Models should be developed to assist choice between liver resection (LR) and transarterial chemoembolization (TACE) for hepatocellular carcinoma. METHODS: After separating 520 cases from 5 hospitals into training (n = 302) and validation (n = 218) data sets, we weighted the cases to control baseline difference and ensured the causal effect between treatments (LR and TACE) and estimated progression-free survival (PFS) difference. A noninvasive PFS model was constructed with clinical factors, radiological characteristics, and radiomic features. We compared our model with other 4 state-of-the-art models. Finally, patients were classified into subgroups with and without significant PFS difference between treatments. RESULTS: Our model included treatments, age, sex, modified Barcelona Clinic Liver Cancer stage, fusion lesions, hepatocellular carcinoma capsule, and 3 radiomic features, with good discrimination and calibrations (area under the curve for 3-year PFS was 0.80 in the training data set and 0.75 in the validation data set; similar results were achieved in 1- and 2-year PFS). The model had better accuracy than the other 4 models. A nomogram was built, with different scores assigned for LR and TACE. Separated by the threshold of score difference between treatments, for some patients, LR provided longer PFS and might be the better option (training: hazard ratio [HR] = 0.50, P = 0.014; validation: HR = 0.52, P = 0.026); in the others, LR provided similar PFS with TACE (training: HR = 0.84, P = 0.388; validation: HR = 1.14, P = 0.614). TACE may be better because it was less invasive. DISCUSSION: We propose an individualized model predicting PFS difference between LR and TACE to assist in the optimal treatment choice.

18.
Cereb Cortex ; 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31408101

RESUMO

The aim of this study was to develop and validate a method of disease classification for bipolar disorder (BD) by functional activity and connectivity using radiomics analysis. Ninety patients with unmedicated BD II as well as 117 healthy controls underwent resting-state functional magnetic resonance imaging (rs-fMRI). A total of 4 types of 7018 features were extracted after preprocessing, including mean regional homogeneity (mReHo), mean amplitude of low-frequency fluctuation (mALFF), resting-state functional connectivity (RSFC), and voxel-mirrored homotopic connectivity (VMHC). Then, predictive features were selected by Mann-Whitney U test and removing variables with a high correlation. Least absolute shrinkage and selection operator (LASSO) method was further used to select features. At last, support vector machine (SVM) model was used to estimate the state of each subject based on the selected features after LASSO. Sixty-five features including 54 RSFCs, 7 mALFFs, 1 mReHo, and 3 VMHCs were selected. The accuracy and area under curve (AUC) of the SVM model built based on the 65 features is 87.3% and 0.919 in the training dataset, respectively, and the accuracy and AUC of this model validated in the validation dataset is 80.5% and 0.838, respectively. These findings demonstrate a valid radiomics approach by rs-fMRI can identify BD individuals from healthy controls with a high classification accuracy, providing the potential adjunctive approach to clinical diagnostic systems.

19.
EBioMedicine ; 46: 160-169, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31395503

RESUMO

BACKGROUND: We aimed to investigate whether pre-therapeutic radiomic features based on magnetic resonance imaging (MRI) can predict the clinical response to neoadjuvant chemotherapy (NACT) in patients with locally advanced cervical cancer (LACC). METHODS: A total of 275 patients with LACC receiving NACT were enrolled in this study from eight hospitals, and allocated to training and testing sets (2:1 ratio). Three radiomic feature sets were extracted from the intratumoural region of T1-weighted images, intratumoural region of T2-weighted images, and peritumoural region of T2-weighted images before NACT for each patient. With a feature selection strategy, three single sequence radiomic models were constructed, and three additional combined models were constructed by combining the features of different regions or sequences. The performance of all models was assessed using receiver operating characteristic curve. FINDINGS: The combined model of the intratumoural zone of T1-weighted images, intratumoural zone of T2-weighted images,and peritumoural zone of T2-weighted images achieved an AUC of 0.998 in training set and 0.999 in testing set, which was significantly better (p < .05) than the other radiomic models. Moreover, no significant variation in performance was found if different training sets were used. INTERPRETATION: This study demonstrated that MRI-based radiomic features hold potential in the pretreatment prediction of response to NACT in LACC, which could be used to identify rightful patients for receiving NACT avoiding unnecessary treatment.

20.
Nat Commun ; 10(1): 3447, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31371730

RESUMO

Interfacial reactions between electrode and electrolyte are critical, either beneficial or detrimental, for the performance of rechargeable batteries. The general approaches of controlling interfacial reactions are either applying a coating layer on cathode or modifying the electrolyte chemistry. Here we demonstrate an approach of modification of interfacial reactions through dilute lattice doping for enhanced battery properties. Using atomic level imaging, spectroscopic analysis and density functional theory calculation, we reveal aluminum dopants in lithium nickel cobalt aluminum oxide are partially dissolved in the bulk lattice with a tendency of enrichment near the primary particle surface and partially exist as aluminum oxide nano-islands that are epitaxially dressed on the primary particle surface. The aluminum concentrated surface lowers transition metal redox energy level and consequently promotes the formation of a stable cathode-electrolyte interphase. The present observations demonstrate a general principle as how the trace dopants modify the solid-liquid interfacial reactions for enhanced performance.

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