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1.
ESC Heart Fail ; 2021 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33838020

RESUMO

AIMS: The aims of the current study were to evaluate the association between anaemia and all-cause mortality according to chronic kidney disease (CKD) status and to explore at what level of haemoglobin concentration would the all-cause mortality risk increase prominently among CKD and non-CKD patients, respectively. METHODS AND RESULTS: This is a prospective cohort study, and 1559 patients with ischaemic heart failure (IHF) were included (mean age of 63.5 ± 11.0 years, 85.8% men) from December 2015 to June 2019. Patients were divided into the CKD (n = 481) and non-CKD (n = 1078) groups based on the estimated glomerular filtration rate of 60 mL/min/1.73 m2 . In the CKD group, the incidence rate of all-cause mortality in anaemic and non-anaemic patients was 15.4 per 100 person-years and 10.8 per 100 person-years, respectively, with an incidence rate ratio of 1.42 (95% confidence interval: 1.00-2.02; P-value = 0.05). In the non-CKD group, the incidence rate of all-cause mortality in anaemic and non-anaemic patients was 9.8 per 100 person-years and 5.5 per 100 person-years, respectively, with an incidence rate ratio of 1.78 (95% confidence interval: 1.20-2.59; P-value = 0.005). After a median follow-up of 2.1 years, the cumulative incidence rate of all-cause mortality in anaemic and non-anaemic patients was 41.5% and 44.1% (P-value = 0.05) in the CKD group, and 30.9% and 18.1% (P-value < 0.0001) in the non-CKD group. In the CKD group, cumulative incidence rate of all-cause mortality increased prominently when haemoglobin concentration was below 100 g/L, which was not observed in the non-CKD group. CONCLUSIONS: Results of the current study indicated that among IHF patients, the association between anaemia and all-cause mortality differed by the renal function status. These findings underline the importance to assess mortality risk and manage anaemia among IHF patients according to the renal function status.

2.
Pest Manag Sci ; 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33837633

RESUMO

BACKGROUND: Opsins are crucial for animal vision. The identity and function of opsins in Plutella xylostella remain unknown. The aim of the research is to confirm which opsin gene(s) contribute to phototaxis of P. xylostella. RESULTS: LW-opsin, BL-opsin and UV-opsin, were identified in the P. xylostella genome. LW-opsin was more highly expressed than the other two opsin genes, and all three genes were specifically expressed in the head. Three P. xylostella strains, LW-13 with a 13-bp deletion in LW-opsin, BL + 2 with a 2-bp insertion in BL-opsin, and UV-29 with a 5-bp insertion and a 34-bp deletion in UV-opsin, were established from the strain G88 using the CRISPR/Cas9 system. Among the three opsin-knockout strains, only male and female LW-13 exhibited weaker phototaxis to lights of different wavelengths and white light than G88 at 2.5 lx due to defective locomotion, and LW-13 was defective to sense white, green and IR lights. The locomotion of LW-13 was reduced compared with G88 at 2.5, 10, 20, 60, 80, 100, and 200 lx under the green light, but the locomotion of LW-13 female was recovered at 80, 100 and 200 lx. The defective phototaxis to the green light of male LW-13 was not affected by light intensity, while the defective phototaxis to the green light of female LW-13 was recovered at 10, 20, 60, 80, 100, and 200 lx. CONCLUSION: LW-opsin is involved in light sensing and locomotion of P. xylostella, providing a potential target gene for controlling the pest.

3.
BMC Cancer ; 21(1): 221, 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33663422

RESUMO

BACKGROUND: Predicting the possibility of ipsilateral lateral cervical lymph node metastasis (ipsi-LLNM) was crucial to the operation plan for patients with papillary thyroid carcinoma (PTC). This study aimed to investigate the independent risk factors for ipsi-LLNM in PTC patients by combining dual-energy computed tomography (DECT) with thyroid function indicators. METHODS: We retrospectively enrolled 406 patients with a pathological diagnosis of PTC from Jan 2016 to Dec 2019. Ensure the DECT images were clear and the thyroid function indicators were complete. Univariate and multivariate logistic analyses explored the independent risk factors for ipsi-LLNM. To evaluate the cutoff value of each risk factor by using receiver operating characteristic (ROC) curves. RESULTS: A total of 406 patients with PTC were analyzed, including 128 with ipsi-LLNM and 278 without ipsi-LLNM. There were statistical differences of parameters between the two groups (P < .0001), including serum Tg, Anti-Tg, Anti-TPO, the volume of the primary lesion, calcification, extrathyroidal extension (ETE), and iodine concentration (IC) in the arterial and the venous phases. Independent risk factors for ipsi-LLNM included serum Tg, Anti-Tg, ETE, and IC in the arterial and the venous phases (P < .05). The combined application of the above independent risk factors can predict the possibility of ipsi-LLNM, with an AUC of 0.834. Ipsi-LLNM was more likely to occur when the following conditions were met: with ETE, Tg >  100.01 ng/mL, Anti-Tg >  89.43 IU/mL, IC in arterial phase > 3.4 mg/mL and IC in venous phase > 3.1 mg/mL. CONCLUSIONS: The combined application of DECT quantitative parameters and thyroid function indicators can help clinicians accurately predict ipsi-LLNM before surgery, thereby assisting the individualized formulation of surgical procedures.

4.
Eur Radiol ; 2021 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-33585995

RESUMO

OBJECTIVES: The purpose of this study was to compare the reproducibility and diagnostic agreement of high-resolution vessel wall imaging (HR-VWI) and time-of-flight magnetic resonance angiography (TOF-MRA) with digital subtraction angiography (DSA) to evaluate intracranial arterial stenosis. METHODS: We retrospectively enrolled patients who underwent HR-VWI and TOF-MRA with suspected intracranial artery disease and had DSA results from our institutional imaging database. Two neuroradiologists separately and independently evaluated anonymous image data for the stenotic lesions. DSA was analyzed by two neurointerventionalists and it served as a standard criterion. The reproducibility of these two MR techniques was determined by the intraclass correlation coefficients (ICCs). The diagnostic agreement to DSA was assessed by the concordance correlation coefficients (CCCs). RESULTS: A total of 246 lesions from 106 individuals were analyzed for stenotic degrees. The total intra-observer and inter-observer reproducibility of HR-VWI was excellent for identifying stenosis and better than of TOF-MRA. The overall concordance of HR-VWI with DSA was excellent with CCC = 0.932, whereas TOF-MRA was 0.694. In addition, HR-VWI could provide additional vessel wall information. CONCLUSIONS: HR-VWI has more advantages over TOF-MRA, such as better reproducibilities and diagnostic agreements with DSA to analyze intracranial arterial stenosis. It provides additional information that helps in clinical diagnosis and management. KEY POINTS: • High-resolution vessel wall imaging can assess intracranial arterial stenosis with a better reproducibility than TOF-MRA and has a higher diagnostic agreement with DSA. • High-resolution vessel wall imaging had a higher diagnostic agreement with DSA compared with TOF-MRA. • Apart from evaluating vascular stenosis, HR-VWI provided additional vessel wall information to help in clinical diagnosis.

5.
Eur Radiol ; 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33566147

RESUMO

OBJECTIVES: There is close relationship between lenticulostriate arteries (LSAs) and lacunar infarctions (LIs) of the basal ganglia. The study aims to visualize the LSAs using high-resolution vessel wall imaging (VWI) on 3T system and explore the correlation between LSAs and LIs. METHODS: Fifty-six patients with LIs in basal ganglia, and 44 age-matched control patients were enrolled and analyzed retrospectively. The raw VWI images were reformatted into coronal slices in minimum intensity projection for further observation of LSAs. The risk factors of LIs in basal ganglia were analyzed by univariate and multivariate logistic regression. The correlation and linear regression analysis between the LSAs and LIs, ipsilateral MCA-M1 plaques were investigated. RESULTS: The total number (p < 0.01) and length (p < 0.01) of LSAs were statistically different between basal ganglias with and without LIs. The total number of LSAs and ipsilateral MCA-M1 plaques were independently related to LIs in basal ganglias. The mean length of LSAs were negatively correlated with number (r = - 0.33, p = 0.002) and volume (r = - 0.37, p = 0.001) of LIs. Age, drinking history, and mean length of LSAs were associated with LI occurrence in basal ganglia, and mean length of LSAs was correlated with larger volume of LIs. CONCLUSIONS: Number of LSA reduction and ipsilateral MCA-M1 plaques were associated with the presence of LIs in basal ganglias. Age increasing, drinking history, and shorter LSAs were correlated with the increasing of LIs. KEY POINTS: • Patients with LIs tend to have shorter LSAs. • The characteristics of LSAs and ipsilateral MCA-M1 plaques are associated with LIs in basal ganglias. • Age, drinking history, and mean length of LSAs are correlated with LI features in basal ganglias.

6.
Atherosclerosis ; 319: 72-78, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33486353

RESUMO

BACKGROUND AND AIMS: Intracranial atherosclerotic disease (ICAD) is a major etiologic cause for acute ischemic stroke (AIS) and transient ischemic attack (TIA). The study was designed to investigate if differential morphological features exist in symptomatic atherosclerotic lesions between AIS and TIA patients. METHODS: The culprit plaques from 45 AIS patients and 42 TIA patients were analyzed for the degree of stenosis, vessel wall irregularity, normalized wall index (NWI), remodeling index, plaque-wall contrast ratio (CR), high signal intensity on T1-weighted images, plaque enhancement ratio and enhancement grade. These plaque features along with clinical characteristics were compared between AIS and TIA groups as well as between their stenosis degree-matched subgroups. RESULTS: Overall, grade 2 enhancement (OR 3.85, 95%CI 1.42-10.46, p = 0.006) and hyperlipidemia (OR 3.04, 95%CI 1.13-8.22, p = 0.025) were independent indicators for AIS, whereas high NWI (OR 1.47, 95%CI 0.76-2.86, p = 0.004) was associated with TIA. In the comparison between the subgroups with moderate (30%-69%) stenosis, high plaque-wall CR (OR 5.38, 95%CI 1.39-20.75, p = 0.008) was associated with AIS, whereas high NWI (OR 2.50, 95%CI 0.61-10.00, p = 0.006) was associated with TIA. CONCLUSIONS: Our study reveals differential morphological features in symptomatic ICAD lesions between AIS and TIA patients. Probing these features with MR vessel wall imaging may provide insights into the prognosis of patients with ICAD.

7.
Eur Radiol ; 2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33512568

RESUMO

OBJECTIVES: To quantitatively evaluate the volume of the ischemic penumbra using susceptibility-weighted imaging and mapping (SWIM) of asymmetrical prominent cortical veins (APCVs) in patients with acute ischemic stroke. METHODS: Eighty-five eligible patients with acute ischemic stroke on admission within 12 h from symptom onset were studied. The APCVs on SWIM were quantitatively (SWI-volume) and semi-quantitatively (SWI-Alberta Stroke Program Early CT Score, SWI-ASPECTS) evaluated to calculate mismatch. To assess the diagnostic efficacy of APCVs on SWIM, comparative analyses were performed between SWIvolume-DWI mismatch and SWIASPECTS-DWI mismatch, using PWI-DWI mismatch as a reference. Correlations were calculated between the mismatches, as well as between SWI-volume and time-to-maximum (Tmax) > 6 s volume. Additionally, each of these mismatches was correlated with the National Institute of Health Stroke Scale (NIHSS). RESULTS: The sensitivity, negative predictive value, and accuracy of SWIvolume-DWI mismatch were demonstrably higher than SWIASPECTS-DWI mismatch (100% vs. 53.7%, 100% vs. 9.5%, 97.7% vs. 54.5%, respectively). A significant positive correlation was found between SWIvolume-DWI and PWI-DWI mismatch (r = 0.691, p < 0.01), as well as between SWI-volume and Tmax > 6 s volume (r = 0.786, p < 0.001). A significant negative correlation was found between SWIvolume-DWI mismatch and NIHSS (r = - 0.360, p = 0.022), as well as between SWIASPECTS-DWI mismatch and NIHSS (r = - 0.499, p = 0.001). CONCLUSIONS: SWIvolume-DWI mismatch had higher diagnostic efficacy than SWIASPECTS-DWI mismatch in defining the ischemic penumbra and showed good consistency with PWI-DWI mismatch in acute ischemic stroke. Quantitation of APCVs using SWIM provided an accurate method for determining hypoperfusion and provided a reliable method to reflect the hypoxia of penumbra. KEY POINTS: • SWIvolume-DWI mismatch has higher diagnostic efficacy than SWIASPECTS-DWI mismatch in defining the ischemic penumbra. • SWIvolume-DWI mismatch shows good consistency with PWI-DWI mismatch in managing penumbra in acute ischemic stroke. • Quantitation of APCV volume using SWIM provided an accurate method for determining the hypoperfusion area and provided a reliable method to reflect the hypoxia of penumbra.

8.
Nat Commun ; 11(1): 6090, 2020 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-33257700

RESUMO

Intracranial aneurysm is a common life-threatening disease. Computed tomography angiography is recommended as the standard diagnosis tool; yet, interpretation can be time-consuming and challenging. We present a specific deep-learning-based model trained on 1,177 digital subtraction angiography verified bone-removal computed tomography angiography cases. The model has good tolerance to image quality and is tested with different manufacturers. Simulated real-world studies are conducted in consecutive internal and external cohorts, in which it achieves an improved patient-level sensitivity and lesion-level sensitivity compared to that of radiologists and expert neurosurgeons. A specific cohort of suspected acute ischemic stroke is employed and it is found that 99.0% predicted-negative cases can be trusted with high confidence, leading to a potential reduction in human workload. A prospective study is warranted to determine whether the algorithm could improve patients' care in comparison to clinicians' assessment.

9.
Sci Rep ; 10(1): 20508, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33239656

RESUMO

Anaemia is the most common complication of myeloma and is associated with worse clinical outcomes. Although marrow replacement with myeloma cells is widely considered a mechanistic rationale for anaemia, the exact process has not been fully understood. Our large cohort of 1363 myeloma patients had more than 50% of patients with moderate or severe anaemia at the time of diagnosis. Anaemia positively correlated with myeloma cell infiltration in the bone marrow (BM) and worse patient outcomes. The quantity and erythroid differentiation of HSPCs were affected by myeloma cell infiltration in the BM. The master regulators of erythropoiesis, GATA1 and KLF1, were obviously downregulated in myeloma HSPCs. However, the gene encoding the chemokine CCL3 showed significantly upregulated expression. Elevated CCL3 in the BM plasma of myeloma further inhibited the erythropoiesis of HSPCs via activation of CCL3/CCR1/p38 signalling and suppressed GATA1 expression. Treatment with a CCR1 antagonist effectively recovered GATA1 expression and rescued erythropoiesis in HSPCs. Myeloma cell infiltration causes elevated expression of CCL3 in BM, which suppresses the erythropoiesis of HSPCs and results in anaemia by downregulating the level of GATA1 in HSPCs. Thus, our study indicates that targeting CCL3 would be a potential strategy against anaemia and improve the survival of myeloma patients.

10.
Brain Imaging Behav ; 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32909105

RESUMO

The purpose of this study was to investigate cerebral blood flow (CBF) changes in hemodialysis patients with arterial spin labeling (ASL) and to correlate these changes with clinical risk factors and neurocognitive function. Thirty-two hemodialysis patients and 35 age-, sex-, and education-matched healthy controls (HCs) were recruited in this prospective study. The Mini-Mental State Examination (MMSE) was performed to evaluate neurocognitive function. Pulsed ASL was performed to measure CBF. Two independent sample t-test was used to explore the CBF difference between the patients and HCs. Multiple stepwise regression was used to investigate the risk factors for CBF in patients. Correlation analysis was used to explore the relationship between the MMSE scores and CBF changes with and without adjusting for anemia status. Compared to HCs, the hemodialysis patients showed significantly increased CBF in some neurocognition-related cerebral regions (all P < 0.001, Bonferroni corrected). Increased CBF in the right opercular and triangular part of the inferior frontal gyrus correlated with the poorer MMSE scores (r = -0.502, P = 0.004; r = -0.423, P = 0.018, FDR corrected) and these correlations still remained after adjusting for anemia status (r = -0.516, P = 0.005; r = -0.439, P = 0.019, FDR corrected). The increased dialysis duration, and decreased hemoglobin, hematocrit, and serum phosphorus were predictive risk factors for increased CBF (P < 0.05). In conclusion, long-term hemodialysis patients had increased CBF, which correlated with neurocognitive impairment, and after adjusting for the effect of anemia, the correlation still remained.

11.
Eur Radiol ; 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32997174

RESUMO

OBJECTIVES: We aimed to investigate differential characteristics of plaque in the middle cerebral artery (MCA) and hemodynamics in patients with ischemic stroke and transient ischemic attack (TIA), and to develop a predictive model for the presence of ischemic stroke and neurological impairment. METHODS: Sixty-seven patients with acute ischemic events in MCA territory who underwent high-resolution vessel wall imaging between September 2016 and August 2018 were reviewed retrospectively. Patients were assigned to either the stroke group or TIA group, according to diffusion-weighted imaging and neurological examination. Plaque characteristics and anterograde score (AnS) were calculated. Tmax > 6.0-s volume was acquired by RApid Processing of perfusIon and Diffusion software. Multivariate logistic regression analysis and multiple linear regression analysis were performed to establish a predictive model for irreversible infarction occurrence and clinical severity. RESULTS: Forty-five patients were assigned to the stroke group, and 22 were assigned to the TIA group. Plaque length, intraplaque hemorrhage (IPH), enhancement, AnS, and Tmax > 6.0-s volumes were significantly different between the two groups (p < 0.05). IPH and AnS were independent predictors for patients with stroke (p = 0.020 and 0.034, respectively). Tmax > 6.0-s volume, IPH, hypertension, and AnS were associated with high National Institutes of Health Stroke Scale (NIHSS) scores (all p < 0.05, R = 0.725, and adjusted R2 = 0.494). CONCLUSIONS: IPH and AnS are useful in predicting stroke occurrence. Tmax > 6.0-s volume, IPH, hypertension, and AnS are associated with neurological impairment of the patients. KEY POINTS: • Ischemic stroke and TIA patients have different plaque characteristics and hemodynamics. • Intraplaque hemorrhage and anterograde score have high diagnostic efficiency for ischemic stroke. • The combination of Tmax > 6.0-s volume, intraplaque hemorrhage, hypertension, and anterograde score can predict the National Institutes of Health Stroke Scale scores of patients.

12.
Sensors (Basel) ; 20(18)2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32948053

RESUMO

Analogue-to-digital converters (ADC) using oversampling technology and the Σ-∆ modulation mechanism are widely applied in digital audio systems. This paper presents an audio modulator with high accuracy and low power consumption by using a discrete second-order feedforward structure. A 5-bit successive approximation register (SAR) quantizer is integrated into the chip, which reduces the number of comparators and the power consumption of the quantizer compared with flash ADC-type quantizers. An analogue passive adder is used to sum the input signals and it is embedded in a SAR ADC composed of a capacitor array and a dynamic comparator which has no static power consumption. To validate the design concept, the designed modulator is developed in a 180 nm CMOS process. The peak signal to noise distortion ratio (SNDR) is calculated as 106 dB and the total power consumption of the chip is recorded as 3.654 mW at the chip supply voltage of 1.8 V. The input sine wave of 0 to 25 kHz is sampled at a sampling frequency of 3.2 Ms/s. Moreover, the results achieve a 16-bit effective number of bits (ENOB) when the amplitude of the input signal is varied between 0.15 and 1.65 V. By comparing with other modulators which were realized by a 180 nm CMOS process, the proposed architecture outperforms with lower power consumption.

13.
Eur Radiol ; 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32740814

RESUMO

OBJECTIVES: To assess plaque vulnerability of the middle cerebral artery (MCA) using strategically acquired gradient echo (STAGE) versus high-resolution vessel wall MRI (hr-vwMRI), and explore the relationship between plaque characteristics and misery downstream perfusion. METHODS: Ninety-one patients with single MCA atherosclerotic plaques underwent STAGE and hr-vwMRI were categorized into a group with misery perfusion and a group without based on the Alberta Stroke Program Early CT score (MTT-ASPECTS) with a threshold of 6. Plaque characteristics including inner lumen area (IWA), susceptibility, presence of hyperintensity within plaque (HIP), surface irregularity, stenosis degree, remodeling index, lipid ratio, and enhancement grade were compared between the two groups. The vulnerability of each plaque was retrospectively assessed on both STAGE and hr-vwMRI according to the combination of plaque features. Logistic regression analysis and ROC curve were performed to evaluate the effect of plaque characteristics on the presence of misery perfusion. RESULTS: Taking hr-vwMRI as the reference, STAGE showed good efficiency in detecting vulnerable plaques. Patients with misery perfusion had less IWA, higher stenosis degree, more irregular surface and HIP, higher enhancement grade, and susceptibility (p < 0.01 for all). Higher susceptibility and stenosis degree were independent predictors for the occurrence of misery perfusion (p = 0.025, p = 0.048). The AUC was 0.900 for the combination of the two variables. CONCLUSION: STAGE shows good efficiency to assess MCA plaque vulnerability versus hr-vwMRI. Plaque susceptibility evaluated using STAGE provides incremental value to predict misery perfusion combined with hr-vwMRI plaque features. KEY POINTS: • STAGE has good efficiency in evaluating MCA plaque vulnerability versus hr-vwMRI. • Higher plaque susceptibility assessed using STAGE and higher grade luminal stenosis based on hr-vwMRI attribute to misery downstream perfusion. • STAGE provides incremental value on the understanding of plaque vulnerability in addition to conventional hr-vwMRI.

14.
J Med Chem ; 63(18): 10396-10411, 2020 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-32847363

RESUMO

Aldo-keto reductase (AKR) 1C3 catalyzes the synthesis of active androgens that promote the progression of prostate cancer. AKR1C3 also contributes to androgen-independent cell proliferation and survival through the metabolism of prostaglandins and reactive aldehydes. Because of its elevation in castration-resistant prostate cancer (CRPC) tissues, AKR1C3 is a promising therapeutic target for CRPC. In this study, we found a novel potent AKR1C3 inhibitor, N-(4-fluorophenyl)-8-hydroxy-2-imino-2H-chromene-3-carboxamide (2d), and synthesized its derivatives with IC50 values of 25-56 nM and >220-fold selectivity over other AKRs (1C1, 1C2, and 1C4). The structural factors for the inhibitory potency were elucidated by crystallographic study of AKR1C3 complexes with 2j and 2l. The inhibitors suppressed proliferation of prostate cancer 22Rv1 and PC3 cells through both androgen-dependent and androgen-independent mechanisms. Additionally, 2j and 2l prevented prostate tumor growth in a xenograft mouse model. Furthermore, the inhibitors significantly augmented apoptotic cell death induced by anti-CRPC drugs (abiraterone or enzalutamide).

15.
Eur Radiol ; 30(9): 5170-5182, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32350658

RESUMO

OBJECTIVES: To build models based on conventional logistic regression (LR) and machine learning (ML) algorithms combining clinical, morphological, and hemodynamic information to predict individual rupture status of unruptured intracranial aneurysms (UIAs), afterwards tested in internal and external validation datasets. METHODS: Patients with intracranial aneurysms diagnosed by computed tomography angiography and confirmed by invasive cerebral angiograph or clipping surgery were included. The prediction models were developed based on clinical, aneurysm morphological, and hemodynamic parameters by conventional LR and ML methods. RESULTS: The training, internal validation, and external validation cohorts were composed of 807 patients, 200 patients, and 108 patients, respectively. The area under curves (AUCs) of conventional LR models 1 (clinical), 2 (clinical and aneurysm morphological), and 3 (clinical, aneurysm morphological and hemodynamic characteristics) were 0.608, 0.765, and 0.886, respectively (all p < 0.05). The AUCs of ML models using random forest (RF), multilayer perceptron (MLP), and support vector machine (SVM) were 0.871, 0.851, and 0.863, respectively. There were no difference among AUCs of conventional LR, RF, and SVM (all p > 0.05/6), while the AUC of MLP was lower than that of conventional LR (p = 0.0055). CONCLUSION: Hemodynamic parameters play an important role in the prediction performance of the models. ML methods cannot outperform conventional LR in prediction models for rupture status of UIAs integrating clinical, aneurysm morphological, and hemodynamic parameters. KEY POINTS: • The addition of hemodynamic parameters can improve prediction performance for rupture status of unruptured intracranial aneurysms. • Machine learning algorithms cannot outperform conventional logistic regression in prediction models for rupture status integrating clinical, aneurysm morphological, and hemodynamic parameters. • Models integrating clinical, aneurysm morphological, and hemodynamic parameters may help choose the optimal management.

16.
Eur Radiol ; 30(9): 5110-5119, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32307565

RESUMO

OBJECTIVES: This study aimed to compare the performance of strategically acquired gradient echo (STAGE)-derived MR angiography and time-of-flight MR angiography (TOF-MRA) in visualization of leptomeningeal collaterals (LMCs). METHODS: Between May 2018 and January 2020, 75 participants (47 healthy volunteers and 28 intracranial atherosclerotic disease [ICAD] patients) undergoing TOF-MRA and STAGE-MRA were prospectively included. Image quality was scored at the internal carotid artery (ICA) terminus, proximal middle cerebral artery (MCA), and LMCs. Quantitative analysis included calculation of contrast-to-noise ratios (CNRs) in the M1-4 segments and number of LMCs counted in the line signal intensity profiles. Comparisons of image qualitative scores, CNRs, and number of LMCs were calculated using the Wilcoxon rank-sum test. RESULTS: Image qualitative scores were significantly higher in STAGE-MRA than in TOF-MRA for the ICA terminus, proximal MCA, and LMCs (ps < 0.05) in 75 participants. When referred to digital subtraction angiography (DSA) in 25 ICAD patients, STAGE-MRA showed higher qualitative scores only at LMCs. CNRs in the M1-4 segments were significantly higher in STAGE-MRA than in TOF-MRA (218.7 ± 90.7 vs 176.2 ± 72.6, 195.7 ± 86.0 vs 146.6 ± 71.7, 176.4 ± 71.6 vs 125.8 ± 61.1, 126.2 ± 62.9 vs 78.8 ± 43.6; all ps < 0.001). STAGE-MRA showed more LMCs (11.4 ± 3.4) than TOF-MRA (8.4 ± 3.3) with p < 0.05. CONCLUSIONS: STAGE-MRA might be superior to TOF-MRA in qualitative and quantitative assessment of LMCs in both healthy volunteers and ICAD patients; thus, it may serve as an alternative method in evaluating LMC. KEY POINTS: • Strategically acquired gradient echo (STAGE)-derived magnetic resonance angiography is a newly developed sequence with a pair of rephasing/dephasing gradient echoes. • STAGE-MRA enables higher image qualitative score, improves contrast-to-noise ratio, and shows greater number of leptomeningeal collaterals (LMCs) in healthy volunteers and patients with intracranial atherosclerotic disease. • LMC visualization by STAGE-MRA shows good to excellent inter-observer agreement.

17.
ACS Appl Mater Interfaces ; 12(11): 13156-13164, 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32083457

RESUMO

Although desirable in next-generation flexible electronics, fabricating hybrid film materials with excellent integration of mechanical and thermally conductive yet electrically insulating properties is still a challenge. In mollusk nacre, a small volume of the chitin nanofiber framework hosts 95 vol % CaCO3 microplatelets, enabling the high-loading natural composites to exhibit a ductile deformation behavior. Inspired by this, we fabricate a large-area, boron nitride-based bio-inspired paper using a facile sol-gel-film conversion approach, in which BN microplatelets with a loading of 40-80 wt % are embedded into a 3D poly(p-phenylene benzobisoxazole) nanofiber framework. Because of the vital role of the 3D nanofiber framework, the BN-based paper exhibits plastic-like ductility (38-80%), ultrahigh toughness (10-100 MJ m-3), and good folding endurance. The high-loading BN platelets form an oriented, percolative network and endow the paper with outstanding in-plane thermal conductivity (77.1-214.2 W m-1 K-1) comparable to that of some metals, such as aluminum alloys (108-230 W m-1 K-1). Using the electrically insulating BN-based paper as a flexible substrate, we demonstrate its promising application for lowering the temperature of electronic devices.

18.
Int J Comput Assist Radiol Surg ; 15(4): 715-723, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32056126

RESUMO

PURPOSE: Cerebrovascular aneurysms are being observed with rapidly increasing incidence. Therefore, tools are needed for accurate and efficient detection of aneurysms. We used deep learning techniques with CT angiography acquired from multiple medical centers and different machines to develop and evaluate an automatic detection model. METHODS: In this study, we have introduced a deep learning model, the faster RCNN model, in order to develop a tool for automatic detection of aneurysms from medical images. The inputs of the model were 2D nearby projection (NP) images from 3D CTA, which were made by the NP method proposed in this study. This method made aneurysms clearly visible on images and improved the model's performance. The study included 311 patients with 352 aneurysms, selected from three hospitals, and 208 and 103 of these patients, respectively, were randomly selected to train and test the models. RESULTS: The sensitivity of the trained model was 91.8%. For aneurysm sizes larger than 3 mm, the sensitivity of successful aneurysm detection was 96.7%. We achieved state-of-the-art sensitivity for > 3 mm aneurysms. The sensitivities also indicated that there was no significant difference among aneurysms at different locations in the body. Computing time for the detection process was less than 25 s per case. CONCLUSIONS: We successfully developed a deep learning model that can automatically detect aneurysms. The model performed well for aneurysms of different sizes or in different locations. This finding indicates that the deep learning model has the potential to vastly improve clinician performance by providing automated aneurysm detection.


Assuntos
Angiografia Cerebral/métodos , Aprendizado Profundo , Processamento de Imagem Assistida por Computador/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Bases de Dados Factuais , Humanos , Sensibilidade e Especificidade
19.
ACS Nano ; 14(1): 611-619, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31891484

RESUMO

The rapid development of modern electrical equipment toward miniaturization and high power puts forward stringent requirements to the mechanical reliability, dielectric property, and heat resistance of electrical insulating materials. Simultaneous integration of all these properties for mica-based materials remains unresolved. Herein, inspired by the three-dimensional (3D) chitin nanofiber framework within the layered architecture of natural nacre, we report a large-area layered mica-based nanopaper containing a 3D aramid nanofiber framework, which is prepared by a sol-gel-film transformation process. The coupling of 3D aramid nanofiber framework and oriented mica nanoplatelets imparts the nanopaper with good mechanical strength, particularly outstanding ductility (close to 80%) and toughness (up to 109 MJ m-3), which are 4-240 and 6-220 times higher than those of all other nacre-mimetics. Meanwhile, the excellent mechanical properties are integrated with high dielectric strength (164 kV mm-1), excellent heat resistance (Tg = 268 °C), good solvent resistance, and nonflammability, much better than conventional mica-based materials. Additionally, we successfully demonstrate its continuous production in the form of nanotape. The fabulous multiproperty combination and continuous production capability render the mica-based nanopaper a very promising electrical insulating material in miniaturized high-power electrical equipment.

20.
Macromol Rapid Commun ; 41(2): e1900533, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31856366

RESUMO

Mussel-inspired polymers attract much research interest due to their potential as effective adhesives. In this work, a new kind of mussel-inspired polymer, poly(dopamine phosphonate-co-PEGMA), is prepared via a one-pot multicomponent polymerization system. The multicomponent polymerization system refers to a combination of multicomponent Kabachnik-Fields (KF) reaction and reversible addition-fragmentation chain transfer (RAFT) polymerization system. Reactants are converted to dopamine phosphonate monomers in situ through the KF reaction and polymerized simultaneously along with poly(ethylene glycol methyl ether) methacrylate (PEGMA) co-monomers by the RAFT process in a one-pot operation. Target polymers with dopamine phosphonate as side groups and well-defined polymer structures are thus facilely and successfully prepared. Afterwards, a series of polymers with various ratios of dopamine phosphonates as well as the crosslinked polymer analogues are prepared. Benefiting from the dopamine phosphonate side groups, aqueous solutions of those polymers show potential as effective adhesives in both dry and wet conditions, and their adhesive strengths are highly related to ratios of dopamine phosphonates in the polymers. Those polymers are non-cytotoxic and show strong bonding affinities on various substrates including metals, polymers, and bovine bones, suggesting their potential as environmentally friendly general adhesives in broad areas.


Assuntos
Bivalves/química , Dopamina/química , Metacrilatos/química , Polietilenoglicóis/química , Polímeros/química , Adesivos , Animais , Organofosfonatos/química , Polimerização , Resistência ao Cisalhamento
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