Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 42
Filter
1.
BMC Med Imaging ; 24(1): 153, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38902645

ABSTRACT

BACKGROUND: While there is a scarcity of studies utilizing strain elastography (SE) for the endometrium, commonly used gynecologic ultrasound instruments are equipped with built-in elastography modalities, primarily SE. With the objective of facilitating comprehensive examinations for gynecologic patients on a single ultrasound instrument, we undertook this study. Therefore, our aim was to study the value of SE ultrasonography in the assessment of endometrial elasticity in normal women. METHODS: Three hundred and twenty normal women were recruited at our hospitals from November 2021 to December 2022. Each volunteer underwent a transvaginal two-dimensional (2D) and SE ultrasound during either the endometrial proliferative or secretory phase. The 2D ultrasound indices obtained included endometrial thickness, echo type (type A, B, and C), and blood flow grading (grades 0, 1, 2, and 3). SE indices obtained included endometrial strain values, myometrial strain values, and endometrial strain ratios. Differences in endometrial ultrasound indices between different menstrual cycles and different age groups were compared. RESULTS: Comparison of 2D ultrasound parameters revealed that endometrial thickness in the proliferative phase endometrium group was smaller than that in the secretory phase endometrium group, with a statistically significant difference. Additionally, there was a statistically significant difference in endometrial echo types between the two groups, while the disparity in endometrial blood flow grading was not significant. Regarding SE parameters, the median and mean values of endometrial strain ratio in the proliferative phase endometrium group were smaller than those in the secretory phase endometrium group, showing a statistically significant difference. However, there were no significant differences observed between the two groups in endometrial strain and myometrial strain in the fundus. Furthermore, there were no significant differences in any of the endometrial ultrasound indices among the different age groups. CONCLUSIONS: SE can reflect changes in endometrial stiffness in different menstrual cycles and is an important tool for assessing endometrial softness.


Subject(s)
Elasticity Imaging Techniques , Endometrium , Humans , Female , Elasticity Imaging Techniques/methods , Endometrium/diagnostic imaging , Endometrium/blood supply , Adult , Middle Aged , Young Adult , Menstrual Cycle
2.
Environ Geochem Health ; 46(7): 222, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38849580

ABSTRACT

In previous studies, iron-based nanomaterials, especially biochar (BC)-supported sulfidized nanoscale zero-valent iron (S-nZVI/BC), have been widely used for the remediation of soil contaminants. However, its potential risks to the soil ecological environment are still unknown. This study aims to explore the effects of 3% added S-nZVI/BC on soil environment and microorganisms during the remediation of Cd contaminated yellow-brown soil of paddy field. The results showed that after 49 d of incubation, S-nZVI/BC significantly reduced physiologically based extraction test (PBET) extractable Cd concentration (P < 0.05), and increased the immobilization efficiency of Cd by 16.51% and 17.43% compared with S-nZVI and nZVI/BC alone, respectively. Meanwhile, the application of S-nZVI/BC significantly increased soil urease and sucrase activities by 0.153 and 0.446 times, respectively (P < 0.05), improving the soil environmental quality and promoting the soil nitrogen cycle and carbon cycle. The results from the analysis of the 16S rRNA genes indicated that S-nZVI/BC treatment had a minimal effect on the bacterial community and did not appreciably alter the species of the original dominant bacterial phylum. Importantly, compared to other iron-based nanomaterials, incorporating S-nZVI/BC significantly increased the soil organic carbon (OC) content and decreased the excessive release of iron (P < 0.05). This study also found a significant negative correlation between OC content and Fe(II) content (P < 0.05). It might originate from the reducing effect of Fe-reducing bacteria, which consumed OC to promote the reduction of Fe(III). Accompanying this process, the redistribution of Cd and Fe mineral phases in the soil as well as the generation of secondary Fe(II) minerals facilitated Cd immobilization. Overall, S-nZVI/BC could effectively reduce the bioavailability of Cd, increase soil nutrients and enzyme activities, with less toxic impacts on the soil microorganisms.


Subject(s)
Cadmium , Charcoal , Iron , Soil Microbiology , Soil Pollutants , Charcoal/chemistry , Cadmium/chemistry , Iron/chemistry , Oryza , Soil/chemistry , Bacteria/metabolism , Environmental Restoration and Remediation/methods , RNA, Ribosomal, 16S , Biodegradation, Environmental
3.
Acad Radiol ; 2024 May 29.
Article in English | MEDLINE | ID: mdl-38816317

ABSTRACT

BACKGROUND: To investigate the association between cardiovascular risk estimated using the Framingham Risk Score (FRS) and carotid stiffening determined using ultrafast pulse wave velocity (ufPWV) measurements in apparently healthy individuals. METHODS: We enrolled 1034 apparently healthy participants without known cardiovascular disease who underwent ufPWV measurements. Clinical and laboratory findings, carotid intima-media thickness (cIMT), pulse wave velocity at the beginning of systole (PWV-BS), and pulse wave velocity at the end of systole (PWV-ES) were assessed. In FRS assessments based on major cardiovascular risk factors (CVRFs), participants were assigned into three risk categories: low risk (<10%, n = 679), intermediate risk (10-20%, n = 191), and high risk (>20%, n = 164); the low-risk category was further subdivided into three subcategories: < 1% (n = 58), 1%- 5% (n = 374) and > 5% (n = 247). Multivariate logistic regression analyses with crude and adjusted odds ratios (ORs) were used to evaluate the association of carotid stiffening and FRS-based risk stratification. RESULTS: Carotid stiffening indicated by PWV-BS and PWV-ES differed notably between the FRS-estimated low-risk vs. intermediate-risk and high-risk categories, but only PWV-ES differed notably among the low-risk subcategories (all p < 0.010), and correlated notably with the FRS-estimated risk most obviously in low-risk participants (r = 0.517). In participants with cIMT < 0.050 cm, only PWV-ES differed significantly among the FRS-estimated risk categories (all p < 0.001). Increased PWV-BS (adjusted OR: 1.49; p = 0.003) and PWV-ES (adjusted OR: 1.29; p = 0.007) were both associated with FRS categories independent of conventional CVRFs in low- vs. intermediate-risk categories, but not in low- vs. high-risk categories (all p > 0.050). CONCLUSION: In vivo imaging of carotid stiffening by ufPWV measurements is independently linked to FRS categories, and ufPWV indices may help stratify differing levels of cardiovascular risk in apparently healthy young people. AVAILABILITY OF DATA AND MATERIAL: Data generated or analyzed during the study are available from the corresponding author by reasonable request.

4.
Ultrasonics ; 138: 107263, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38350312

ABSTRACT

Ischemic diseases due to arterial stenosis or occlusion are common and can have serious consequences if untreated. Therapeutic ultrasound like high-intensity focused ultrasound (HIFU) ablates tissues while low-intensity pulsed ultrasound (LIPU) promotes healing at relatively low temperatures. However, blood vessel cooling effect and reduced flow in ischemia impact temperature distribution and ultrasonic treatment efficacy. This work established a rabbit limb ischemia model by ligating the femoral artery, measuring vascular changes and temperature rise during LIPU exposures. Results showed the artery diameter was narrowed by 46.2% and the downstream velocity was reduced by 51.3% after ligation. Finite element simulations verified that the reduced flow velocity impaired heat dissipation, enhancing LIPU-induced heating. Simulation results also suggested the temperature rise was almost related linearly to vessel diameter but decayed exponentially with the increasing flow velocity. Findings indicate that the proposed model could be used as an effectively tool to model the heating effects in ischemic tissues during LIPU treatment. This research on relating varied ischemic flow to LIPU-induced thermal effects is significant for developing safe and efficacious clinical ultrasound hyperthermia treatment protocols for the patients with ischemic diseases.


Subject(s)
Hyperthermia, Induced , Ultrasonic Therapy , Animals , Humans , Rabbits , Constriction, Pathologic , Ultrasonic Therapy/methods , Ischemia/therapy , Ultrasonic Waves , Ultrasonics
5.
Quant Imaging Med Surg ; 14(1): 75-85, 2024 Jan 03.
Article in English | MEDLINE | ID: mdl-38223093

ABSTRACT

Background: The mortality and disability of chronic kidney disease (CKD) are highly linked to the incidence of atherosclerotic cardiovascular events. Numerous clinical biochemical indicators of renal function often only increase in advanced stages of CKD, driving an urgent need for reliable indicators of atherosclerosis in early CKD. Ultrafast pulse wave velocity (ufPWV) can evaluate the stiffness of the straight carotid in vivo and quantitatively reflect the degree of early atherosclerosis. However, the use of ufPWV in CKD has not yet been reported. In this study, we aimed to explore the association between carotid stiffness, quantified using ufPWV, and renal function in CKD patients. Methods: This cross-sectional study enrolled a total of 582 participants between March 2017 and May 2022 in the Affiliated Hospital of Nanjing University of Traditional Chinese Medicine. Among those, 205 individuals without a history of CKD and estimated glomerular filtration rate (eGFR) ≥90 mL/min/1.73 m2 were included as controls. According to the Kidney Disease Outcomes Quality Initiative (K/DOQI) expert group of the American Kidney Foundation staging for CKD, 44 stages 1 and 2 CKD patients were included in the early CKD group, whereas 49 stages 3, 4, and 5 CKD patients were included in the advanced CKD group. Clinical and serum parameters, ultrasonic characteristics including carotid intima-media thickness (cIMT), and pulse wave velocity at the beginning of systole (PWV-BS) and pulse wave velocity at the end of systole (PWV-ES) of systole were analyzed. One-way analysis of variance (ANOVA) and least significant difference (LSD) tests were performed to compare cIMT, PWV-BS, and PWV-ES among subgroups in pairs. Pearson's correlation analysis, scatter plots, and subgroups correlation analysis were used to determine the relationships among ultrasound characteristics (cIMT, PWV-BS, PWV-ES), and major cardiovascular risk factors. Results: PWV-BS and PWV-ES for the early and advanced CKD groups were significantly higher than those for controls (all P<0.05). PWV-ES had the greatest correlation with age (r=0.474, P<0.001). PWV-ES had the greatest increase with age in the early CKD group (r=0.698, P<0.001). Conclusions: ufPWV can be used for the quantitative evaluation of carotid stiffness in CKD patients. PWV-ES may be more advantageous in the assessment of carotid atherosclerosis in early CKD patients.

6.
Eur Radiol ; 34(2): 945-956, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37644151

ABSTRACT

OBJECTIVE: To reduce the number of biopsies performed on benign breast lesions categorized as BI-RADS 4-5, we investigated the diagnostic performance of combined two-dimensional and three-dimensional shear wave elastography (2D + 3D SWE) with standard breast ultrasonography (US) for the BI-RADS assessment of breast lesions. METHODS: A total of 897 breast lesions, categorized as BI-RADS 3-5, were subjected to standard breast US and supplemented by 2D SWE only and 2D + 3D SWE analysis. Based on the malignancy rate of less than 2% for BI-RADS 3, lesions assessed by standard breast US were reclassified with SWE assessment. RESULTS: After standard breast US evaluation, 268 (46.1%) participants underwent benign biopsies in BI-RADS 4-5 lesions. By using separated cutoffs for upstaging BI-RADS 3 at 120 kPa and downstaging BI-RADS 4a at 90 kPa in 2D + 3D SWE reclassification, 123 (21.2%) participants underwent benign biopsy, resulting in a 54.1% reduction (123 versus 268). CONCLUSION: Combining 2D + 3D SWE with standard breast US for reclassification of BI-RADS lesions may achieve a reduction in benign biopsies in BI-RADS 4-5 lesions without sacrificing sensitivity unacceptably. CLINICAL RELEVANCE STATEMENT: Combining 2D + 3D SWE with US effectively reduces benign biopsies in breast lesions with categories 4-5, potentially improving diagnostic accuracy of BI-RADS assessment for patients with breast lesions. TRIAL REGISTRATION: ChiCTR1900026556 KEY POINTS: • Reduce benign biopsy is necessary in breast lesions with BI-RADS 4-5 category. • A reduction of 54.1% on benign biopsies in BI-RADS 4-5 lesions was achieved using 2D + 3D SWE reclassification. • Adding 2D + 3D SWE to standard breast US improved the diagnostic performance of BI-RADS assessment on breast lesions: specificity increased from 54 to 79%, and PPV increased from 54 to 71%, with slight loss in sensitivity (97.2% versus 98.7%) and NPV (98.1% versus 98.7%).


Subject(s)
Breast Neoplasms , Elasticity Imaging Techniques , Female , Humans , Breast/diagnostic imaging , Breast/pathology , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/pathology , Diagnosis, Differential , Elasticity Imaging Techniques/methods , Prospective Studies , Reproducibility of Results , Sensitivity and Specificity , Ultrasonography, Mammary/methods
8.
Front Physiol ; 14: 1177351, 2023.
Article in English | MEDLINE | ID: mdl-37675280

ABSTRACT

Introduction: Accurate contour extraction in ultrasound images is of great interest for image-guided organ interventions and disease diagnosis. Nevertheless, it remains a problematic issue owing to the missing or ambiguous outline between organs (i.e., prostate and kidney) and surrounding tissues, the appearance of shadow artifacts, and the large variability in the shape of organs. Methods: To address these issues, we devised a method that includes four stages. In the first stage, the data sequence is acquired using an improved adaptive selection principal curve method, in which a limited number of radiologist defined data points are adopted as the prior. The second stage then uses an enhanced quantum evolution network to help acquire the optimal neural network. The third stage involves increasing the precision of the experimental outcomes after training the neural network, while using the data sequence as the input. In the final stage, the contour is smoothed using an explicable mathematical formula explained by the model parameters of the neural network. Results: Our experiments showed that our approach outperformed other current methods, including hybrid and Transformer-based deep-learning methods, achieving an average Dice similarity coefficient, Jaccard similarity coefficient, and accuracy of 95.7 ± 2.4%, 94.6 ± 2.6%, and 95.3 ± 2.6%, respectively. Discussion: This work develops an intelligent contour extraction approach on ultrasound images. Our approach obtained more satisfactory outcome compared with recent state-of-the-art approaches . The knowledge of precise boundaries of the organ is significant for the conservation of risk structures. Our developed approach has the potential to enhance disease diagnosis and therapeutic outcomes.

9.
Breast Cancer Res ; 25(1): 61, 2023 05 30.
Article in English | MEDLINE | ID: mdl-37254149

ABSTRACT

BACKGROUND: Multiparametric magnetic resonance imaging (MP-MRI) has high sensitivity for diagnosing breast cancers but cannot always be used as a routine diagnostic tool. The present study aimed to evaluate whether the diagnostic performance of perfluorobutane (PFB) contrast-enhanced ultrasound (CEUS) is similar to that of MP-MRI in breast cancer and whether combining the two methods would enhance diagnostic efficiency. PATIENTS AND METHODS: This was a head-to-head, prospective, multicenter study. Patients with breast lesions diagnosed by US as Breast Imaging Reporting and Data System (BI-RADS) categories 3, 4, and 5 underwent both PFB-CEUS and MP-MRI scans. On-site operators and three reviewers categorized the BI-RADS of all lesions on two images. Logistic-bootstrap 1000-sample analysis and cross-validation were used to construct PFB-CEUS, MP-MRI, and hybrid (PFB-CEUS + MP-MRI) models to distinguish breast lesions. RESULTS: In total, 179 women with 186 breast lesions were evaluated from 17 centers in China. The area under the receiver operating characteristic curve (AUC) for the PFB-CEUS model to diagnose breast cancer (0.89; 95% confidence interval [CI] 0.74, 0.97) was similar to that of the MP-MRI model (0.89; 95% CI 0.73, 0.97) (P = 0.85). The AUC of the hybrid model (0.92, 95% CI 0.77, 0.98) did not show a statistical advantage over the PFB-CEUS and MP-MRI models (P = 0.29 and 0.40, respectively). However, 90.3% false-positive and 66.7% false-negative results of PFB-CEUS radiologists and 90.5% false-positive and 42.8% false-negative results of MP-MRI radiologists could be corrected by the hybrid model. Three dynamic nomograms of PFB-CEUS, MP-MRI and hybrid models to diagnose breast cancer are freely available online. CONCLUSIONS: PFB-CEUS can be used in the differential diagnosis of breast cancer with comparable performance to MP-MRI and with less time consumption. Using PFB-CEUS and MP-MRI as joint diagnostics could further strengthen the diagnostic ability. Trial registration Clinicaltrials.gov; NCT04657328. Registered 26 September 2020. IRB number 2020-300 was approved in Chinese PLA General Hospital. Every patient signed a written informed consent form in each center.


Subject(s)
Breast Neoplasms , Multiparametric Magnetic Resonance Imaging , Humans , Female , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/pathology , Contrast Media , Sensitivity and Specificity , Prospective Studies , Ultrasonography, Mammary/methods , Magnetic Resonance Imaging/methods
10.
Quant Imaging Med Surg ; 13(3): 1711-1722, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-36915304

ABSTRACT

Background: The sonography-based risk stratification of thyroid nodules is based on the different sonographic features of benign and malignant thyroid nodules. The American College of Radiology (ACR) Thyroid Imaging Reporting and Data System (TIRADS) and the Chinese-TIRADS define different risks for malignancy categories and the size criteria for fine-needle aspiration (FNA). Few studies have compared their diagnostic performance and FNA management approaches. Thus, we sought to compare the diagnostic performance and FNA management approaches of the ACR-TIRADS and Chinese-TIRADS based on surgical histological evidence. Methods: This retrospective study included patients with complete thyroid ultrasound images and histologic evidence who were consecutively selected from The Affiliated Hospital of Nanjing University of Chinese Medicine. A total of 333 nodules from 252 patients with definitive surgical histological findings were examined. Ultrasonography categories and FNA management proposals were assigned according to the ACR-TIRADS and Chinese-TIRADS. The thyroid nodules were divided into 2 groups based on a cut-off size of 1 cm. The diagnostic performance and recommended and unnecessary FNA rates for each group were compared for both systems. Results: Overall, 280 malignant thyroid nodules (84.1%) and 53 benign nodules (15.9%) were analyzed. Across all groups, the ACR-TIRADS had higher sensitivity, specificity, positive and negative predictive values, and accuracy, and a higher area under the curve (AUC) than the Chinese-TIRADS. However, there was a significant difference in the negative predictive value between the ACR-TIRADS and Chinese-TIRADS of <1 and ≥1 cm, and the overall AUCs differed significantly (39.5% vs. 35.1%, P=0.007 for <1 cm; 70.0% vs. 62.8%, P=0.014 for ≥1 cm; 0.843 vs. 0.806, P=0.037 for all). The rate for recommending the FNA of the nodules in the ACR-TIRADS was lower than that in the Chinese-TIRADS (25.2% vs. 56.5%, P<0.0001), but there was no significant difference between the ACR-TIRADS and Chinese-TIRADS in terms of the unnecessary FNA rate (14.3% vs. 13.8%, P=0.931). The kappa statistics for the consistency of the ACR-TIRADS and Chinese-TIRADS FNA recommendations for nodules sized ≥1.0 to <1.5, ≥1.5 to <2.5, and ≥2.5 cm were 0.084, 0.635, and 0.909, respectively. Conclusions: The ACR-TIRADS had slightly better diagnostic performance and a lower recommended FNA rate than the Chinese-TIRADS for thyroid nodules. For thyroid nodules ≥1.5 cm in size, the FNA recommendations of the 2 guidelines had good consistency.

11.
J Digit Imaging ; 36(3): 947-963, 2023 06.
Article in English | MEDLINE | ID: mdl-36729258

ABSTRACT

Accurate prostate segmentation in ultrasound images is crucial for the clinical diagnosis of prostate cancer and for performing image-guided prostate surgery. However, it is challenging to accurately segment the prostate in ultrasound images due to their low signal-to-noise ratio, the low contrast between the prostate and neighboring tissues, and the diffuse or invisible boundaries of the prostate. In this paper, we develop a novel hybrid method for segmentation of the prostate in ultrasound images that generates accurate contours of the prostate from a range of datasets. Our method involves three key steps: (1) application of a principal curve-based method to obtain a data sequence comprising data coordinates and their corresponding projection index; (2) use of the projection index as training input for a fractional-order-based neural network that increases the accuracy of results; and (3) generation of a smooth mathematical map (expressed via the parameters of the neural network) that affords a smooth prostate boundary, which represents the output of the neural network (i.e., optimized vertices) and matches the ground truth contour. Experimental evaluation of our method and several other state-of-the-art segmentation methods on datasets of prostate ultrasound images generated at multiple institutions demonstrated that our method exhibited the best capability. Furthermore, our method is robust as it can be applied to segment prostate ultrasound images obtained at multiple institutions based on various evaluation metrics.


Subject(s)
Prostate , Prostatic Neoplasms , Male , Humans , Prostate/diagnostic imaging , Neural Networks, Computer , Prostatic Neoplasms/diagnostic imaging , Ultrasonography , Models, Theoretical , Image Processing, Computer-Assisted/methods
12.
Ultrasonography ; 42(1): 89-99, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36588181

ABSTRACT

PURPOSE: The aim of this study was to assess carotid stiffening in a pre-hypertensive (PHT) population using ultrafast pulse wave velocity (ufPWV). METHODS: This study retrospectively enrolled 626 individuals who underwent clinical interviews, serum tests, and assessments of the systolic blood pressure (SBP), diastolic blood pressure (DBP), carotid intima-media thickness (cIMT), pulse wave velocity-beginning of systole (PWV-BS), and pulse wave velocity-end of systole (PWV-ES) between January 2017 and December 2021. The patients were divided into three groups according to their blood pressure (BP)-normal BP (NBP): SBP <130 mmHg and DBP <80 mmHg (n=215); PHT: 130 mmHg≤SBP<140 mmHg and/or 80 mmHg≤DBP<90 mmHg (n=119); hypertensive (HT): SBP ≥140 mmHg and/or DBP ≥90 mmHg (n=292). Correlation analyses and comparisons were performed among the groups and in the cIMT subgroups (cIMT ≥0.050 cm and <0.050 cm). RESULTS: cIMT and PWV-ES significantly differed among the BP groups (P<0.05). The BP groups had similar PWV-BS when cIMT <0.050 cm or cIMT ≥0.050 cm (all P>0.05). However, the NBP group had a notably lower PWV-ES than the PHT (P<0.001 and P=0.024) and HT (all P<0.001) groups in both cIMT categories, while the PWV-ES in the PHT group were not significantly lower than in the HT group (all P>0.05). CONCLUSION: Carotid morphological and biomechanical properties in the PHT group differed from those in the NBP group. ufPWV could be used for an early evaluation of carotid stiffening linked to pre-hypertension.

13.
J Clin Hypertens (Greenwich) ; 25(2): 199-212, 2023 02.
Article in English | MEDLINE | ID: mdl-36695004

ABSTRACT

Evidence of the triglyceride-glucose (TyG) index as an independent predictor of arterial stiffness in stage 1 hypertension patients is scarce. This study aimed to explore the association between TyG index and arterial stiffness in this population. A total of 1041 individuals from 32 centers with normal/elevated blood pressure (BP, <130/80 mmHg; 345 men (33%); median age, 37 years) and 585 stage 1 hypertension patients (BP ≥130/80 and <140/90 mmHg; 305 men (52%); median age, 47 years) were prospectively enrolled. Arterial stiffness was determined by measuring carotid ultrafast pulse-wave velocity (ufPWV). TyG index was calculated as ln (fasting triglyceride (TG) × fasting blood glucose/2). Patients with a higher TyG index tended to have higher ufPWV. The TyG index was positively associated with ufPWV at the end of systole in stage 1 hypertension patients after adjusting for confounding factors (ß for per unit .48), and restricted cubic spline analysis confirmed a linear association. Subgroup analyses in terms of age, sex, and body mass index yielded similar results. However, no significant relationship was observed between the TyG index and ufPWV in the population with normal/elevated BP. The fully adjusted ß between ufPWV and the TyG index was higher than the TG/high-density lipoprotein cholesterol ratio, TG, and pulse pressure. In conclusion, patients with a higher TyG index had greater arterial stiffness, and the TyG index independently and positively correlated with arterial stiffness in stage 1 hypertension patients. The TyG index may provide a simple and reliable marker to monitor arterial stiffness in hypertensive patients.


Subject(s)
Hypertension , Vascular Stiffness , Male , Humans , Adult , Middle Aged , Blood Pressure/physiology , Hypertension/diagnosis , Glucose , Triglycerides , Vascular Stiffness/physiology , Blood Glucose , Risk Factors , Biomarkers
14.
Polymers (Basel) ; 14(22)2022 Nov 21.
Article in English | MEDLINE | ID: mdl-36433175

ABSTRACT

The increase in the use of additive manufacturing (AM) has led to the need for filaments with specific and functional properties in face of requirements of structural parts production. The use of eco-friendly reinforcements (i.e., natural fibers) as an alternative to those more traditional synthetic counterparts is still scarce and requires further investigation. The main objective of this work was to develop short curauá fiber-reinforced polylactic acid (PLA) composites made via fused deposition modeling. Three different fiber lengths (3, 6, and 8 mm), and three concentrations in terms of weight percentage (2, 3.5, and 5 wt.%) were used to fabricate reinforced PLA filaments. Tensile and flexural tests in accordance with their respective American Society for Testing and Materials (ASTM) standards were performed. A thermal analysis was also carried out in order to investigate the thermal stability of the new materials. It was found that the main driving factor for the variation in mechanical properties was the fiber weight fraction. The increase in fiber length did not provide any significant benefit on the mechanical properties of the curauá fiber-reinforced PLA composite printed parts. The composites produced with PLA filaments reinforced by 3 mm 2% curauá fiber presented the overall best mechanical and thermal properties of all studied groups. The curauá fiber-reinforced PLA composites made via fused deposition modeling may be a promising innovation to improve the performance of these materials, which might enable them to serve for new applications.

15.
Front Oncol ; 12: 878104, 2022.
Article in English | MEDLINE | ID: mdl-35747834

ABSTRACT

Accurate prostate segmentation in transrectal ultrasound (TRUS) is a challenging problem due to the low contrast of TRUS images and the presence of imaging artifacts such as speckle and shadow regions. To address this issue, we propose a semi-automatic model termed Hybrid Segmentation Model (H-SegMod) for prostate Region of Interest (ROI) segmentation in TRUS images. H-SegMod contains two cascaded stages. The first stage is to obtain the vertices sequences based on an improved principal curve-based model, where a few radiologist-selected seed points are used as prior. The second stage is to find a map function for describing the smooth prostate contour based on an improved machine learning model. Experimental results show that our proposed model achieved superior segmentation results compared with several other state-of-the-art models, achieving an average Dice Similarity Coefficient (DSC), Jaccard Similarity Coefficient (Ω), and Accuracy (ACC) of 96.5%, 95.2%, and 96.3%, respectively.

16.
Ultrasound Med Biol ; 48(8): 1528-1536, 2022 08.
Article in English | MEDLINE | ID: mdl-35595590

ABSTRACT

To establish and preliminarily validate an individualized reference of carotid stiffness quantified by ultrafast pulse wave velocity (ufPWV), our study included 225 healthy individuals in the modeling cohort and 628 individuals in the validation cohort. All participants underwent assessment of carotid intima-media thickness (cIMT), pulse wave velocity-beginning of systole and pulse wave velocity-end of systole (PWV-ES). A threshold equation of estimated PWV-ES was obtained by multiple linear regression analysis in the modeling cohort as follows: estimated PWV-ES (m/s) = 0.080 × age (y) + 0.767 × low-density lipoprotein (mmol/L) + 0.040 × systolic blood pressure (mm Hg) + 0.372 × sex (male = 1, female = 0) - 2.803. With this equation, the validation cohort was divided into the low PWV-ES (actual PWV-ES ≤ estimated PWV-ES) and high PWV-ES (actual PWV-ES > estimated PWV-ES) groups. A clear boundary was found to be present between the low PWV-ES and high PWV-ES groups in the validation cohort. Participants with increasing PWV-ES increased with age gradually. We further subdivided participants into cIMT subgroups using a cutoff thickness of 0.050 cm. Diagnostic performance analysis revealed that the sensitivity and specificity of the threshold equation were 78.9% and 73.9%, respectively. We established and validated a novel individualized reference equation for estimated PWV-ES, which can likely expand the application of prospective ufPWV assessment.


Subject(s)
Carotid Arteries/diagnostic imaging , Carotid Intima-Media Thickness , Pulse Wave Analysis , Vascular Stiffness/physiology , Cohort Studies , Female , Humans , Linear Models , Male , Prospective Studies , Sensitivity and Specificity , Ultrasonography
17.
Ultrasonography ; 41(3): 462-472, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35589550

ABSTRACT

PURPOSE: The present study investigated the association between Systematic COronary Risk Evaluation (SCORE)-estimated cardiovascular risk and carotid stiffening in a middle-aged population using ultrafast pulse wave velocity (ufPWV). METHODS: This study enrolled 683 participants without known cardiovascular disease or diabetes mellitus who underwent ufPWV measurements. Clinical interviews, physical examinations, laboratory findings, carotid intima-media thickness (cIMT), pulse wave velocity (PWV) at the beginning of systole (PWV-BS), and PWV at the end of systole (PWV-ES) were assessed. Each participant underwent an assessment of SCORE risk based on major cardiovascular risk factors (CVRFs), including age, sex, smoking, systolic blood pressure (SBP), and total cholesterol (TC). Crude and adjusted odds ratios (ORs) with 95% confidence intervals and ordinal logistic regression were used. Overall CVRFs were adjusted to assess ORs. RESULTS: cIMT and carotid stiffening in PWV-BS and PWV-ES were significantly different between sex subgroups (all P<0.05), but only PWV-ES increased gradually in age and SCORE-estimated risk subgroups (all P<0.05). Compared with cIMT (r=0.388, P<0.001) and PWV-BS (r=0.159, P<0.001), PWV-ES was more strongly correlated with SCORE categories (r=0.405, P<0.001). Higher PWV-ES values were associated with SCORE categories independently of sex, SBP, TC, and smoking in moderate-risk and high-risk subgroups (OR, 1.63; P<0.001 and OR, 2.12; P=0.024, respectively), but were not independent of age in all risk subgroups (all P>0.05). CONCLUSION: Carotid stiffening quantified by ufPWV is linked to SCORE categories, and elevated PWV-ES may aid in cardiovascular risk stratification.

18.
Comput Methods Programs Biomed ; 219: 106752, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35338887

ABSTRACT

BACKGROUND AND OBJECTIVE: Accurate and robust prostate segmentation in transrectal ultrasound (TRUS) images is of great interest for image-guided prostate interventions and prostate cancer diagnosis. However, it remains a challenging task for various reasons, including a missing or ambiguous boundary between the prostate and surrounding tissues, the presence of shadow artifacts, intra-prostate intensity heterogeneity, and anatomical variations. METHODS: Here, we present a hybrid method for prostate segmentation (H-ProSeg) in TRUS images, using a small number of radiologist-defined seed points as the prior points. This method consists of three subnetworks. The first subnetwork uses an improved principal curve-based model to obtain data sequences consisting of seed points and their corresponding projection index. The second subnetwork uses an improved differential evolution-based artificial neural network for training to decrease the model error. The third subnetwork uses the parameters of the artificial neural network to explain the smooth mathematical description of the prostate contour. The performance of the H-ProSeg method was assessed in 55 brachytherapy patients using Dice similarity coefficient (DSC), Jaccard similarity coefficient (Ω), and accuracy (ACC) values. RESULTS: The H-ProSeg method achieved excellent segmentation accuracy, with DSC, Ω, and ACC values of 95.8%, 94.3%, and 95.4%, respectively. Meanwhile, the DSC, Ω, and ACC values of the proposed method were as high as 93.3%, 91.9%, and 93%, respectively, due to the influence of Gaussian noise (standard deviation of Gaussian function, σ = 50). Although the σ increased from 10 to 50, the DSC, Ω, and ACC values fluctuated by a maximum of approximately 2.5%, demonstrating the excellent robustness of our method. CONCLUSIONS: Here, we present a hybrid method for accurate and robust prostate ultrasound image segmentation. The H-ProSeg method achieved superior performance compared with current state-of-the-art techniques. The knowledge of precise boundaries of the prostate is crucial for the conservation of risk structures. The proposed models have the potential to improve prostate cancer diagnosis and therapeutic outcomes.


Subject(s)
Brachytherapy , Prostatic Neoplasms , Humans , Image Processing, Computer-Assisted/methods , Male , Models, Theoretical , Prostate/diagnostic imaging , Prostatic Neoplasms/diagnostic imaging , Ultrasonography
19.
J Environ Manage ; 302(Pt A): 113980, 2022 Jan 15.
Article in English | MEDLINE | ID: mdl-34689028

ABSTRACT

Since climate change is the paramount concern of recent literature, macroeconomic factors such as green growth and economic globalization may play an integral role in achieving ecological sustainability in the presence of eco-innovation. However, the combined contributions of green growth, economic globalization, and eco-innovation towards achieving ecological sustainability are missing from the existing knowledge. Therefore, we investigate the combined influence of these variables in the presence of human capital, financial development, and gross domestic product on ecological footprint per capita for a panel of 20 Organization for Economic Co-operation and Development (OECD) countries from 1990 through 2017. The method of panel quantile regression is used to produce sound results across varying levels of the ecological footprint of OECD nations. The main results are as follows: firstly, green productivity growth linearly and non-linearly mitigates the ecological degradation, presenting a more pronounced ecological protection impact for higher quantiles, followed by medium and lower quantiles. Secondly, economic globalization manifests mixed effects: it induces ecological deterioration impact in the absence of its interaction with eco-innovation, while it brings about an ecological protection impact with the interaction term. Thirdly, eco-innovation demonstrates an ecological protection impact for all quantiles, with the most influential impact in countries with higher ecological footprint per capita, followed by medium and lower footprints. Based on empirical results, we propose productive utilization of environmental resources for ecological sustainability through product and process innovation and efficient management practices. Besides, we recommend cultivating energy-efficient and clean environmental technologies for long-term ecological sustainability.


Subject(s)
Economic Development , Organisation for Economic Co-Operation and Development , Carbon Dioxide , Gross Domestic Product , Humans , Internationality
20.
Sci Total Environ ; 806(Pt 4): 150969, 2022 Feb 01.
Article in English | MEDLINE | ID: mdl-34656600

ABSTRACT

Because of their highly persistent, bioaccumulative and toxic properties, short-chain chlorinated paraffins (SCCPs) have become emerging contaminants and have been included in Annex A (elimination) of the Stockholm Convention since 2017. The contamination of SCCPs has been observed in the environment and biota worldwide but has not been detected in Taiwanese river ecosystems. Thus, this study aimed to determine the occurrence of SCCPs in sediments and fish from 30 major rivers in Taiwan and to evaluate the risk of SCCPs to river ecosystems and human health. The concentrations of SCCPs in sediments and fish ranged from ND (not detected) to 12.6 mg/kg dw and ND to 2.07 mg/kg ww, respectively. The concentrations of SCCPs in sediments were significantly correlated with some indicators of the discharge sources and water quality variables, indicating that SCCPs were released via human activities and various discharges into rivers and accumulated in sediments. The bioaccumulation of SCCPs in fish exhibited species-specific profiles and was related to environmental contamination levels and the living pattern and trophic level of the fish. The SCCP levels in sediments from 20 major rivers in Taiwan might pose a potential ecological risk to river ecosystems according to the criteria of the Federal Environmental Quality Guidelines in Canada, the biota-sediment accumulation factor and the risk quotient. Consumption of SCCP-contaminated river fish by different gender and age groups showed no significant health risk to residents in Taiwan evaluated by the estimated daily intake and hazard quotient. However, there was a health concern for the 0- to 3-year-old group due to the consumption of contaminated river fish at a bioaccessibility of 100% for SCCPs by the margin of exposure. Routine monitoring of SCCPs in river ecosystems is needed to protect aquatic organisms and human health.


Subject(s)
Hydrocarbons, Chlorinated , Paraffin , Animals , Child, Preschool , China , Ecosystem , Environmental Monitoring , Humans , Hydrocarbons, Chlorinated/analysis , Infant , Infant, Newborn , Paraffin/analysis , Risk Assessment , Taiwan
SELECTION OF CITATIONS
SEARCH DETAIL
...