Objectives
We sought to build a high-risk plaque MRI-based model (HRPMM) using radiomics features and machine learning for differentiating symptomatic from asymptomatic carotid plaques.
Materials and ...methods
One hundred sixty-two patients with carotid stenosis were randomly divided into training and test cohorts. Multi-contrast MRI including time of flight (TOF), T1- and T2-weighted imaging, and contrast-enhanced imaging was done. Radiological characteristics of the carotid plaques were recorded and calculated to build a traditional model. After extracting the radiomics features on these images, we constructed HRPMM with least absolute shrinkage and selection operator algorithm in the training cohort and evaluated its performance in the test cohort. A combined model was also built using both the traditional and radiomics features. The performance of all the models in the identification of high-risk carotid plaque was compared.
Results
Intraplaque hemorrhage and lipid-rich necrotic core were independently associated with clinical symptoms and were used to build the traditional model, which achieved an area under the curve (AUC) of 0.825 versus 0.804 in the training and test cohorts. The HRPMM and the combined model achieved an AUC of 0.988 versus 0.984 and of 0.989 versus 0.986 respectively in the two cohorts. Both the radiomics model and combined model outperformed the traditional model, whereas the combined model showed no significant difference with the HRPMM.
Conclusions
Our MRI-based radiomics model can accurately distinguish symptomatic from asymptomatic carotid plaques. It is superior to the traditional model in the identification of high-risk plaques.
Key Points
• Carotid plaque multi-contrast MRI stores other valuable information to be further exploited by radiomics analysis.
• Radiomics analysis can accurately distinguish symptomatic from asymptomatic carotid plaques.
• The radiomics model is superior to the traditional model in the identification of high-risk plaques.
Purpose
To identify triple-negative (TN) breast cancer imaging biomarkers in comparison to other molecular subtypes using multiparametric MR imaging maps and whole-tumor histogram analysis.
Materials ...and methods
This retrospective study included 134 patients with invasive ductal carcinoma. Whole-tumor histogram-based texture features were extracted from a quantitative ADC map and DCE semi-quantitative maps (washin and washout). Univariate analysis using the Student’s
t
test or Mann–Whitney
U
test was performed to identify significant variables for differentiating TN cancer from other subtypes. The ROC curves were generated based on the significant variables identified from the univariate analysis. The AUC, sensitivity, and specificity for subtype differentiation were reported.
Results
The significant parameters on the univariate analysis achieved an AUC of 0.710 (95% confidence interval CI 0.562, 0.858) with a sensitivity of 63.6% and a specificity of 73.1% at the best cutoff point for differentiating TN cancers from Luminal A cancers. An AUC of 0.763 (95% CI 0.608, 0.917) with a sensitivity of 86.4% and a specificity of 72.2% was achieved for differentiating TN cancers from human epidermal growth factor receptor 2 (HER2) positive cancers. Also, an AUC of 0.683 (95% CI 0.556, 0.809) with a sensitivity of 54.5% and a specificity of 83.9% was achieved for differentiating TN cancers from non-TN cancers. There was no significant feature on the univariate analysis for TN cancers versus Luminal B cancers.
Conclusions
Whole-tumor histogram-based imaging features derived from ADC, along with washin and washout maps, provide a non-invasive analytical approach for discriminating TN cancers from other subtypes.
Key Points
•
Whole-tumor histogram-based features on MR multiparametric maps can help to assess biological characterization of breast cancer.
• Histogram-based texture analysis may predict the molecular subtypes of breast cancer.
• Combined DWI and DCE evaluation helps to identify triple-negative breast cancer.
Objectives
To assess whole-liver texture analysis on T1 maps for risk stratification of advanced fibrosis in patients with suspected nonalcoholic fatty liver disease (NAFLD).
Methods
This ...retrospective study included 53 patients. Histogram and texture parameters (volume, mean, SD, median, 5th percentile, 95th percentile, skewness, kurtosis, diff-entropy, diff-variance, contrast, and entropy) of T1 maps were calculated based on the semi-automatically segmented whole-liver volume. A two-step approach combining the Nonalcoholic Fatty Liver Disease Fibrosis Score (NFS) and Fibrosis-4 Index (FIB-4) with the liver stiffness measurement (LSM) for the risk stratification was used. Univariate analysis was performed to identify significant parameters. Logistic regression models were then run on the significant features. Diagnostic performance was evaluated with receiver operating characteristic (ROC) analysis.
Results
In total, 33 (62%) subjects had a low risk and 20 (38%) subjects had an intermediate-to-high risk of advanced fibrosis. The following significantly different parameters with the best performance were diff-entropy, entropy, and diff-variance, with AUROC 0.837 (95% CI 0.73–0.95), 0.821 (95% CI 0.71–0.94), and 0.807 (95% CI 0.69–0.93). The optimal combination of median, 5th percentile, and diff-entropy as a multivariate model improved the diagnostic performance to diagnose an intermediate-to-high risk of advanced fibrosis with AUROC 0.902(95% CI 0.79–0.97).
Conclusions
Parameters obtained by histogram and texture analysis of T1 maps may be a noninvasive analytical approach for stratifying the risk of advanced fibrosis in NAFLD.
Key Points
•
Variable flip angle (VFA) T1 mapping can be used to acquire 3D T1 maps within a clinically acceptable duration.
•
Whole-liver histogram and texture parameters on T1 maps in patients with NAFLD can distinguish those with an intermediate-to-high risk of advanced fibrosis.
•
The multivariate model of combination of texture parameters improved the diagnostic performance for a high risk of advanced fibrosis and clinical parameters offer no added value to the multivariate model.
Under extreme acidic environments, bacteria exploit several acid resistance (AR) mechanisms for enhancing their survival, which is concerned with several aspects, such as issues in human health and ...fermentation for acidic products. Currently, knowledge of bacterial AR mainly comes from the strong acid (such as hydrochloric acid) stresses, whereas AR mechanisms against organic weak acids (such as acetic acid), which are indeed encountered by bacteria, are less understood. Acetic acid bacteria (AAB), with the ability to produce acetic acid up to 20 g/100 mL, possess outstanding acetic acid tolerance, which is conferred by their unique AR mechanisms, including pyrroloquinoline quinine-dependent alcohol dehydrogenase, acetic acid assimilation and molecular chaperons. The distinguished AR of AAB toward acetic acid may provide a paradigm for research in bacterial AR against weak organic acids. In order to understand AAB's AR mechanism more holistically, omics approaches have been employed in the corresponding field. However, the currently reported transcriptomic study was processed under a low-acidity (1 g/100 mL) environment, which could not reflect the general conditions that AAB are usually faced with. This study performed RNA-Seq transcriptomic analysis investigating AR mechanisms in
CGMCC 1.41, a widely used vinegar-brewing AAB strain, at different stages of fermentation, namely, under different acetic acid concentrations (from 0.6 to 6.03 g/100 mL). The results demonstrated the even and clustered genomic distribution of up- and down-regulated genes, respectively. Difference in AR between AAB and other microorganisms was supported by the down-regulation of urea degradation and trehalose synthesis-related genes in response to acetic acid. Detailed analysis reflected the role of ethanol respiration as the main energy source and the limited effect of acetic acid assimilation on AR during fermentation as well as the competition between ethanol respiratory chain and NADH, succinate dehydrogenase-based common respiratory chain. Molecular chaperons contribute to AR, too, but their regulatory mechanisms require further investigation. Moreover, pathways of glucose catabolism and fatty acid biosynthesis are also related to AR. Finally, 2-methylcitrate cycle was proposed as an AR mechanism in AAB for the first time. This study provides new insight into AR mechanisms of AAB, and it also indicates the existence of numerous undiscovered AR mechanisms.
Objective
To determine whether a radiomics signature (rad-score) outperforms ADC in TSR estimation by developing a radiomics biomarker for preoperative TSR diagnosis in rectal cancer.
Methods
This ...study included 149 patients (119 and 30 in the training and validation cohorts, respectively). All patients underwent T2-weighted, diffusion-weighted, and contrast-enhanced T1-weighted imaging. A rad-score was generated using the least absolute shrinkage and selection operator (LASSO) algorithm and stepwise multivariate logistic regression. Meanwhile, the mean ADCs were calculated from ADC maps. For both the mean ADC and rad-score, binary logistic regression and Spearman correlation coefficients were used to determine associations with the TSR, and the area under the receiver operating characteristic (ROC) curve was used to assess the diagnostic performance. The reliability of the rad-score was quantified by comparing the imaging-estimated TSR with the actual TSR of each patient.
Results
Both the mean ADC and rad-score were positively correlated with the TSR in the training cohort (mean ADC:
p
< 0.001,
r
= 0.566; rad-score:
p
< 0.001,
r
= 0.559) and validation cohort (mean ADC:
p
< 0.001,
r
= 0.671; rad-score:
p
= 0.002,
r
= 0.536). The rad-score, with AUCs of 0.917 (95% CI 0.869–0.965) and 0.787 (95% CI 0.602–0.972) in the training and validation cohorts, respectively, outperformed the mean ADC (training cohort: AUC = 0.776, 95% CI 0.693–0.859; validation cohort: AUC = 0.764, 95% CI 0.592–0.936) in TSR estimation.
Conclusion
The ADC possesses potential diagnostic value for TSR estimation in rectal cancer, and the rad-score shows increased diagnostic value over the ADC and may be a promising supplemental tool for patient stratification and informing decision-making.
Key Points
• Tumor-stroma ratio has been verified as an independent prognostic factor for various solid tumors including rectal cancer.
• The ADC and multiparametric MRI-based radiomics features were significantly and positively correlated with the tumor-stroma ratio in rectal cancer.
• The radiomics signature outperformed the ADC in discriminating TSR in rectal cancer.
Background:
Previous studies have examined patients with chronic lateral ankle instability (CLAI) undergoing open and arthroscopic anterior talofibular ligament (ATFL) reconstruction, reporting ...equivalent clinical results between the 2 procedures. However, data on the magnetic resonance imaging (MRI) outcomes on cartilage health after the 2 procedures are limited.
Purpose:
To compare the cartilage MRI T2 values of the talar and subtalar joints between patients with CLAI undergoing open and arthroscopic ATFL reconstruction.
Study Design:
Cohort study; Level of evidence, 3.
Methods:
A prospective study was conducted on patients who underwent open or arthroscopic ATFL reconstruction between January 2018 and December 2019, with a mean follow-up duration of 3 years. MRI scans and American Orthopaedic Foot & Ankle Society (AOFAS) and Tegner score estimations were completed by patients ≤1 week before surgery, as a baseline measurement, and at a 3-year follow-up. A total of 21 healthy volunteers were included who underwent MRI at baseline. Cartilage health was evaluated using MRI T2 mapping. The talar and subtalar cartilage regions were segmented into 14 subregions.
Results:
At baseline, patients with CLAI had substantially higher T2 values in the medial anterior, medial center, medial posterior, and lateral center regions on the talus compared with the healthy controls (P = .009, .003, .001, and .025, respectively). Remarkable increases in T2 values in the lateral posterior region on the talus were observed from baseline to follow-up in the open group (P = .007). Furthermore, T2 values were considerably higher in the medial center, medial posterior, lateral posterior, and lateral posterior calcaneal facets of the posterior subtalar joint at follow-up in the arthroscopic group compared with the baseline values (P = .025, .002, .006, and .044, respectively). No obvious differences in ΔT2 values were noted between the 2 groups at follow-up. The AOFAS and Tegner scores remarkably improved from baseline to follow-up for the 2 groups (open: 3.25 ± 0.58 vs 5.13 ± 0.81, P < .001; arthroscopic: 3.11 ± 0.90 vs 5.11 ± 1.08, P < .001), with no considerable difference between them.
Conclusion:
The elevated T2 values of cartilage could not be fully recovered after open or arthroscopic ATFL reconstruction. Both arthroscopic and open ATFL reconstruction displayed similar effects on cartilage health concerning ΔT2, but the arthroscopic group demonstrated more degenerative cartilage subregions than the open group.
Purpose
To compare advanced non-parallel transmission zoomed diffusion-weighted imaging (nonPTX zoom-DWI) to conventional DWI (conv-DWI) for the assessment of prostate cancer (PCa).
Methods
This ...retrospective study included 98 patients who underwent conv-DWI, nonPTX zoom-DWI, and T2-weighted imaging of the prostate. The image qualities of the two DWI sets, including the distortion of the prostate and the existence of artifacts, were evaluated. To compare the overall PCa and clinically important PCa (ciPCa) detection ability between the sets, lesions were scored using the Prostate Imaging Reporting and Data System (PI-RADS) version 2. Apparent diffusion coefficient (ADC) values of the lesions were also measured and compared. The Mann–Whitney
U
test was used to compare continuous variables, and the
χ
2
test was used to compare categorical variables. Two-sided
P
values of < 0.05 were considered significant.
Results
Non-PTX zoom-DWI yielded significantly better image quality and image analysis reproducibility than conv-DWI (all
P
< 0.001). Compared with conv-ADC, nonPTX zoom-ADC showed slightly better detection performance for overall PCa (AUC: 0.827 vs. 0.797;
P
= 0.55) and ciPCa (AUC: 0.822 vs. 0.749;
P
= 0.58). At a PI-RADS score of 4 as the cutoff value for PCa prediction, nonPTX zoom-DWI showed significantly higher diagnostic efficiency for overall PCa detection (sensitivity: 87.9% vs. 72.4%; specificity: 87.5% vs. 77.5%; both
P
< 0.05) and ciPCa detection (sensitivity: 86.3% vs. 74.5%; specificity: 72.3% vs. 63.8%; both
P
≤ 0.001).
Conclusion
Non-PTX zoom-DWI yields better image quality and higher PCa detection performance than Conv-DWI.
Graphic Abstract
Operation performance and bacterial community structure of sulfur-based autotrophic denitrification (SAD) based on different sulfur sources served as electron donor was first parallelly compared ...among three sequencing batch reactors. Sulfur and sodium thiosulfate systems achieved similar operation performance and were superior to that of sodium sulfide. When the influent NO
3
−
–N concentration ranged from 50 to 150 mg/L, the effluent NO
3
−
–N concentrations of the sulfur and sodium thiosulfate systems were 0–5.99 mg/L and 0–4.52 mg/L, respectively, without NO
2
−
–N accumulation. However, when the effluent concentration of NO
3
−
–N in the sodium sulfide system was 0–10.38 mg/L, that of NO
2
−
–N in the effluent was 0–39.85 mg/L. In addition, participation of sulfur sources presented obvious pressure on the bacterial community structure based on the high-throughput sequencing. Microbial diversity results indicated that sludge with elemental sulfur as electron donor had the richest microbial diversity, followed by sodium thiosulfate and sodium sulfide. Moreover, sludge with elemental sulfur and sodium thiosulfate as electron donor demonstrated more similar community structure compared with the sludge that denitrified with sodium sulfide according to the microbial similarity analysis. The 9.34%, 24.3% and 29.6% of sequences could be assigned to potential SAD organisms from sludge denitrifying with elemental sulfur, sodium thiosulfate and sodium sulfide, respectively. Furthermore, all sludge denitrifying with different sulfur sources showed an enrichment of separate core functional microorganisms. This study could provide an insight into improving the understanding of SAD in engineering applications.
Although Bisphenol F (BPF), a bisphenol A (BPA) analogue with a similar chemical structure to that of BPA, is widely used in commercial products, little is known about its potential toxic effects on ...the reproductive neuroendocrine system in vivo. The present study aimed to comprehensively evaluate the effects of BPF on the reproductive neuroendocrine system in zebrafish and to assess the potential mechanisms underlying its association with estrogen receptor (ER) and aromatase (AROM) pathways. Long-term exposure to environmentally relevant and low levels of BPF led to increased expression of reproductive neuroendocrine-related genes (kiss1, kiss1r, gnrh3, lhβ, and fshβ) in the zebrafish brain, as well as increased levels of adrenocorticotropic, gonadotropin-releasing, luteinizing, and follicle-stimulating hormones in the zebrafish brain and vitellogenin in the zebrafish liver. In addition, these effects were associated with an increase in erα, erβ, cyp19a, and cyp19b activity. Meanwhile, ER and AROM antagonists, alone or in combination, significantly attenuated the stimulation of kiss1, lhβ, vtg, and gnrh3 expression, thereby suggesting that chronic BPF exposure affects the regulation of the reproductive neuroendocrine system through activation of the ER and AROM pathways. Moreover, since BPF and bisphenol S induced toxic and reproductive neuroendocrine effects similar to those of BPA, the current accepted usage of BPA and its analogs should be reconsidered in the future.
Display omitted
•Low levels of BPF led to increased expression of reproductive neuroendocrine-related genes.•BPF increased hormone levels of ACTH, GnRH, LH, FSH in brain and VTG in liver of zebrafish.•BPF affects reproductive neuroendocrine system through the ER and AROM pathways.•BPF and BPS induced similar toxic and reproductive neuroendocrine effects to those of BPA.
Purpose: To investigate the potential of diffusion kurtosis imaging (DKI) for the assessment of renal fibrosis in chronic kidney disease (CKD), using histopathology as the reference standard.
...Methods: Eighty-nine CKD patients and twenty healthy volunteers were recruited in this study. DKI was performed in all participants and all CKD patients received renal biopsy. The values of mean diffusivity (MD) and mean kurtosis (MK) in the renal cortex and medulla were compared between CKD patients and healthy volunteers. The Spearman correlation coefficient was calculated to assess the relationship between MD, MK values and the estimated glomerular filtration rate (eGFR), serum creatinine (SCr), 24 h urinary protein (24 h-UPRO), histopathological fibrosis score.
Results: The medullary MD values were significantly lower than cortex, while the cortical MK values were significantly lower than medulla for all participants. Renal parenchymal MD values were significantly lower in the CKD patients than healthy controls, whereas MK values were significantly higher in the CKD patients than healthy controls. In the CKD patients, the significantly negative correlation was observed between the renal parenchymal MD values and the 24 h-UPRO, SCr, histopathological fibrosis score, as well as between the renal parenchymal MK values and the eGFR, while the significantly positive correlation was found between the renal parenchymal MD values and the eGFR, as well as between the renal parenchymal MK values and the 24 h-UPRO, SCr, histopathological fibrosis score.
Conclusion: DKI shows great potential in the noninvasive assessment of renal fibrosis in CKD.
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