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Search Results (5,129)

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14 pages, 1182 KiB  
Article
High-Density Lipoprotein-Associated Paraoxonase-1 (PON-1) and Scavenger Receptor Class B Type 1 (SRB-1) in Coronary Artery Disease: Correlation with Disease Severity
by Manish Kumar, Wahid Ali, Kusum Yadav, Swati Kaumri, Sridhar Mishra, Paolo Nardi, Ferdinando Iellamo, Sergio Bernardini, Akshyaya Pradhan and Marco Alfonso Perrone
J. Clin. Med. 2024, 13(18), 5480; https://doi.org/10.3390/jcm13185480 (registering DOI) - 15 Sep 2024
Abstract
Background: Coronary artery disease (CAD) is the leading cause of death worldwide. High-Density lipoprotein (HDL) is a well-established marker associated with CAD. The current research goes beyond the conventional HDL-C measurement in previous studies and dives into the functional intricacies of HDL. By [...] Read more.
Background: Coronary artery disease (CAD) is the leading cause of death worldwide. High-Density lipoprotein (HDL) is a well-established marker associated with CAD. The current research goes beyond the conventional HDL-C measurement in previous studies and dives into the functional intricacies of HDL. By understanding how HDL works, rather than just how much of it exists, we can better tailor diagnostic and therapeutic strategies for CAD and related conditions. Hence, the current study quantifies the serum levels of two novel HDL-associated markers, Paraoxonase-1 (PON-1) and Scavenger Receptor Class B Type 1 (SRB-1), in CAD cases vs. controls. Methods: A total of 92 subjects, including 69 CAD and 23 healthy controls, were included, based on the prevalence of the disease. Further, based on the severity of the disease, CAD cases were subcategorized as CAD-I, -II, and -III. Serum PON-1 and SRB-1 levels were measured and compared between patient and control groups. Results: The levels of PON-1 and SRB-1 (32.6 ng/mL and 12.49 ng/mL) were significantly lower in CAD patients vs. the healthy control, at 60.36 ng/mL and 15.85 ng/mL, respectively (p < 0.000). A further intergroup comparison showed a statistically significant difference between the CAT-I and -III for PON-1 (p < 0.025), the CAT-I and -III, and CAT-II and -III for SRB-1 (p < 0.000). The receiver operating characteristics (ROC) curve showed cutoff values of 48.20 ng/mL and 14.90 ng/mL for PON-1 and SRB-1. Conclusions: The current study found that serum levels of HDL-associated PON-1 and SRB-1 are significantly lower in CAD cases, and were also inversely related to the increasing severity of coronary artery disease. This inference implies that serum PON-1 and SRB-1 could be used as non-invasive tools for the identification of coronary atherosclerosis and risk assessment in CAD cases. Full article
(This article belongs to the Special Issue Cardiovascular Medicine and Cardiac Surgery)
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<p>Scatter plot showing the level of PON-1 in cases and controls, as well as different categories of the CAD severity.</p>
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<p>Scatter plot showing the level of SRB-1 in cases and controls, as well as different categories of the CAD severity.</p>
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<p>ROC curve showing the sensitivity and specificity of PON-1 and SRB-1 in cases and controls and with different categories of CAD severity.</p>
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13 pages, 1096 KiB  
Article
Fibrosis-4 Score Is Associated with Mortality in Hemodialysis Patients with Chronic Viral Hepatitis: A Retrospective Study
by Hao-Hsuan Liu, Chieh-Li Yen, Wen-Juei Jeng, Cheng-Chieh Hung, Ching-Chung Hsiao, Ya-Chung Tian and Kuan-Hsing Chen
Diagnostics 2024, 14(18), 2048; https://doi.org/10.3390/diagnostics14182048 (registering DOI) - 15 Sep 2024
Abstract
BACKGROUND: Chronic hepatitis B and C infections are major causes of morbidity and mortality in end-stage kidney disease (ESKD) patients on hemodialysis (HD). The Fibrosis-4 (FIB-4) score is a non-invasive method to evaluate chronic liver disease. However, it is unclear whether there is [...] Read more.
BACKGROUND: Chronic hepatitis B and C infections are major causes of morbidity and mortality in end-stage kidney disease (ESKD) patients on hemodialysis (HD). The Fibrosis-4 (FIB-4) score is a non-invasive method to evaluate chronic liver disease. However, it is unclear whether there is a connection between the FIB-4 score and major adverse cardiovascular events (MACEs) and mortality in patients on HD. This study investigates the relationship between FIB-4 scores, MACEs, and mortality in HD patients. METHODS: A 5-year retrospective study included 198 HD patients with chronic hepatitis B and C from Chang Gung Memorial Hospital. FIB-4 scores were categorized into high (>2.071), middle (1.030~2.071), and low (<1.030) tertiles for cross-sectional analyses. MACEs and mortality were tracked longitudinally. RESULTS: Patients with high FIB-4 scores had lower hemoglobin and albumin levels. Cox multivariate analysis showed that high FIB-4 scores (aHR: 1.589) and diabetes mellitus (aHR: 5.688) were significant factors for all-cause mortality. The optimal FIB-4 score for 5-year mortality was 2.942. FIB-4 scores were not significant for predicting 5-year MACEs. CONCLUSIONS: High FIB-4 scores are associated with increased 5-year all-cause mortality risk in HD patients with chronic hepatitis virus infection. Full article
(This article belongs to the Section Diagnostic Microbiology and Infectious Disease)
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<p>Flowchart of included patients in this study.</p>
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<p>ROC curve and AUC of the FIB-4 score for identifying 5-year mortality. ROC curve: receiver operating characteristic curve; AUC: area under the curve; FIB-4 score: Fibrosis-4 score.</p>
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<p>Kaplan–Meier plot with the diagnostic point of the FIB-4 score (2.942) for identifying 5-year mortality. Group 1: FIB-4 score ≥ 2.942; Group 2: FIB-4 score &lt; 2.942.</p>
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18 pages, 9120 KiB  
Article
A Spatio-Temporal Capsule Neural Network with Self-Correlation Routing for EEG Decoding of Semantic Concepts of Imagination and Perception Tasks
by Jianxi Huang, Yinghui Chang, Wenyu Li, Jigang Tong and Shengzhi Du
Sensors 2024, 24(18), 5988; https://doi.org/10.3390/s24185988 (registering DOI) - 15 Sep 2024
Abstract
Decoding semantic concepts for imagination and perception tasks (SCIP) is important for rehabilitation medicine as well as cognitive neuroscience. Electroencephalogram (EEG) is commonly used in the relevant fields, because it is a low-cost noninvasive technique with high temporal resolution. However, as EEG signals [...] Read more.
Decoding semantic concepts for imagination and perception tasks (SCIP) is important for rehabilitation medicine as well as cognitive neuroscience. Electroencephalogram (EEG) is commonly used in the relevant fields, because it is a low-cost noninvasive technique with high temporal resolution. However, as EEG signals contain a high noise level resulting in a low signal-to-noise ratio, it makes decoding EEG-based semantic concepts for imagination and perception tasks (SCIP-EEG) challenging. Currently, neural network algorithms such as CNN, RNN, and LSTM have almost reached their limits in EEG signal decoding due to their own short-comings. The emergence of transformer methods has improved the classification performance of neural networks for EEG signals. However, the transformer model has a large parameter set and high complexity, which is not conducive to the application of BCI. EEG signals have high spatial correlation. The relationship between signals from different electrodes is more complex. Capsule neural networks can effectively model the spatial relationship between electrodes through vector representation and a dynamic routing mechanism. Therefore, it achieves more accurate feature extraction and classification. This paper proposes a spatio-temporal capsule network with a self-correlation routing mechaninsm for the classification of semantic conceptual EEG signals. By improving the feature extraction and routing mechanism, the model is able to more effectively capture the highly variable spatio-temporal features from EEG signals and establish connections between capsules, thereby enhancing classification accuracy and model efficiency. The performance of the proposed model was validated using the publicly accessible semantic concept dataset for imagined and perceived tasks from Bath University. Our model achieved average accuracies of 94.9%, 93.3%, and 78.4% in the three sensory modalities (pictorial, orthographic, and audio), respectively. The overall average accuracy across the three sensory modalities is 88.9%. Compared to existing advanced algorithms, the proposed model achieved state-of-the-art performance, significantly improving classification accuracy. Additionally, the proposed model is more stable and efficient, making it a better decoding solution for SCIP-EEG decoding. Full article
(This article belongs to the Section Biomedical Sensors)
27 pages, 8188 KiB  
Article
Decoding Octopus Skin Mucus: Impact of Aquarium-Maintenance and Senescence on the Proteome Profile of the Common Octopus (Octopus vulgaris)
by Sara Pérez-Polo, Alejandro Rivero Mena, Lorena Barros, Paula Borrajo, Manuel Pazos, Mónica Carrera and Camino Gestal
Int. J. Mol. Sci. 2024, 25(18), 9953; https://doi.org/10.3390/ijms25189953 (registering DOI) - 15 Sep 2024
Viewed by 78
Abstract
The common octopus (Octopus vulgaris) is an excellent candidate for aquaculture diversification, due to its biological traits and high market demand. To ensure a high-quality product while maintaining welfare in captive environments, it is crucial to develop non-invasive methods for testing health [...] Read more.
The common octopus (Octopus vulgaris) is an excellent candidate for aquaculture diversification, due to its biological traits and high market demand. To ensure a high-quality product while maintaining welfare in captive environments, it is crucial to develop non-invasive methods for testing health biomarkers. Proteins found in skin mucus offer a non-invasive approach to monitoring octopus welfare. This study compares the protein profiles in the skin mucus of wild, aquarium-maintained, and senescent specimens to identify welfare biomarkers. A tandem mass tag (TMT) coupled with an Orbitrap Eclipse Tribrid mass spectrometer was used to create a reference dataset from octopus skin mucus, identifying 1496 non-redundant protein groups. Although similar profiles were observed, differences in relative abundances led to the identification of potential biomarkers, including caspase-3-like, protocadherin 4, deleted in malignant brain tumors, thioredoxin, papilin, annexin, cofilin and mucin-4 proteins. Some of these proteins also revealed potential as bioactive peptides. This investigation provides the most extensive analysis of the skin mucus proteome in the common octopus and is the first to explore how aquarium maintenance and senescence alter the mucus proteome. This research highlights the potential of skin mucus protein/peptides as non-invasive monitoring biomarkers in cultured animals. Full article
(This article belongs to the Special Issue Marine Omics)
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<p>SDS-PAGE 12% profiles of the skin mucus protein for ten samples (1A, 1S, 2A, 2S, 3W, 3S, 4W, 4S, 5W, 6S); A: aquarium-maintained; W: wild; S: senescent. MW (molecular weight in KDa).</p>
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<p>Heatmap from the proteomics analysis of the skin mucus samples of octopus under the three different conditions: wild group (3W, 4W, 5W), aquarium-maintained group (1A, 2A), and senescent group (1S, 2S, 3S, 4S, 6S). Bars correspond to the up-regulation (red) or down-regulation (green) of particular proteins. Euclidean hierarchical distances were sorted for all samples.</p>
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<p>PCA analysis of the samples grouped by conditions (aquarium-maintained group in blue, wild group in orange, and senescent group in green).</p>
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<p>Volcano plot analysis by condition. (<b>A</b>) Wild group vs. aquarium-maintained group. (<b>B</b>) Aquarium-maintained group vs. senescent group. (<b>C</b>) Wild group vs. senescent group. The red area corresponds to up-regulated proteins and the green area to down-regulated proteins.</p>
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<p>Volcano plot analysis by specimen. (<b>A</b>) Octopus specimen 1: Aquarium-maintained vs. senescent. (<b>B</b>) Octopus specimen 2: Aquarium-maintained vs. senescent. (<b>C</b>) Octopus specimen 3: Wild vs. senescent. (<b>D</b>) Octopus specimen 4: Wild vs. senescent. The red area corresponds to up-regulated proteins and the green area to down-regulated proteins.</p>
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<p>Senescent male vs. senescent female volcano plot. The red area corresponds to up-regulated proteins and the green area to down-regulated proteins.</p>
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<p>Box plot representations of the quantification ratios of selected protein biomarkers by conditions, more abundant in wild (<b>A</b>) and aquarium-maintained groups (<b>B</b>,<b>C</b>).</p>
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<p>Box plot representations of the quantification ratios of selected protein biomarkers by conditions, more abundant in senescent group (<b>A</b>,<b>B</b>) and down-regulated in senescent group (<b>C</b>,<b>D</b>).</p>
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<p>Selected box plot representations of the quantification ratios of selected protein biomarkers by time-course specimen.</p>
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<p>Box plot representations of the quantification ratios of selected protein biomarkers by sex-study of senescent specimens.</p>
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<p>Protein Class of common octopus skin mucus proteome categorized by PANTHER using the gene ID (<a href="https://pantherdb.org/" target="_blank">https://pantherdb.org/</a>, accessed on 20 May 2024).</p>
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<p>Protein network of common octopus skin mucus proteome by STRING software (v.12.0) (accessed on 22 May 2024). Nodes depict the proteins and the interactions between proteins are represented with continuous lines (physical, direct interactions) and dotted lines (functional, indirect interactions).</p>
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10 pages, 12226 KiB  
Article
Exploring Tumor Heterogeneity: Radiogenomic Assessment of ADFP in Low WHO/ISUP Grade Clear Cell Renal Cell Carcinoma
by Federico Greco, Andrea Panunzio, Valerio D’Andrea, Mariavittoria Vescovo, Alessandro Tafuri, Simone Carotti, Bruno Beomonte Zobel and Carlo Augusto Mallio
Cancers 2024, 16(18), 3164; https://doi.org/10.3390/cancers16183164 (registering DOI) - 15 Sep 2024
Viewed by 80
Abstract
This study aimed to investigate the association between metabolic lipid computed tomography (CT) features and adipose differentiation-related protein (ADFP) expression in clear cell renal cell carcinoma (ccRCC), providing insights into non-invasive methods for assessing ADFP expression and tumor characteristics. This study utilized data [...] Read more.
This study aimed to investigate the association between metabolic lipid computed tomography (CT) features and adipose differentiation-related protein (ADFP) expression in clear cell renal cell carcinoma (ccRCC), providing insights into non-invasive methods for assessing ADFP expression and tumor characteristics. This study utilized data from The Cancer Genome Atlas and the Cancer Imaging Archive to analyze genetic alterations and imaging characteristics in ccRCC patients. Tumoral Hounsfield units (HU) analysis and quantification of abdominal adipose tissue compartments were performed using CT images. Statistical analyses were conducted to compare tumoral HU values according to ADFP gene expression and World Health Organization/International Society of Urological Pathology (WHO/ISUP) tumor grade, as well as to explore correlations between tumoral HU values and adipose tissue quantification. Among the 174 identified patients, those with ADFP gene expression showed significantly lower minimum tumoral HU values in low-grade cancers compared to high-grade cancers. Similarly, patients with low-grade cancers expressing ADFP exhibited lower minimum tumoral HU values compared to those without ADFP expression. Negative correlations were observed between minimum tumoral HU values and visceral adipose tissue, subcutaneous adipose tissue, and total adipose tissue in both ccRCC patients with and without ADFP expression. This study reveals a significant association between metabolic lipid CT features and ADFP expression in ccRCC patients. Lower minimum tumoral HU values, suggestive of higher intracellular lipid accumulation, were observed in tumors with low WHO/ISUP grade and ADFP expression. Full article
(This article belongs to the Collection Molecular Signaling Pathways and Networks in Cancer)
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<p>Scatterplots illustrating the relationship between minimum tumoral HU and quantification of adipose tissue compartments according to ADFP expression [(<b>A</b>): yes vs. (<b>B</b>): no].</p>
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<p>Unenhanced axial CT images of patients with low WHO/ISUP grade ccRCC with ADFP expression (<b>A</b>) and low WHO/ISUP grade ccRCC without ADFP expression (<b>B</b>) show yellow ROIs with different minimum tumor HU values (HU −35 and −7, respectively).</p>
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<p>The histological images illustrate two samples of ccRCC (same patients of <a href="#cancers-16-03164-f002" class="html-fig">Figure 2</a>) stained with hematoxylin and eosin (original magnification 20×). Image (<b>A</b>): ccRCC with ADFP expression characterized by cells with nested architecture, small nuclei, inconspicuous nucleoli, and abundant clear cytoplasm. Image (<b>B</b>): ccRCC without ADFP expression characterized by cells with granular eosinophilic cytoplasm.</p>
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16 pages, 275 KiB  
Article
Characterization and Automatic Discrimination between Predominant Hypoperfusion and Hyperperfusion Stages of NPDR
by Luís Mendes, Luísa Ribeiro, Inês Marques, Conceição Lobo and José Cunha-Vaz
J. Pers. Med. 2024, 14(9), 977; https://doi.org/10.3390/jpm14090977 (registering DOI) - 14 Sep 2024
Viewed by 213
Abstract
Background/Objectives: Diabetic retinopathy (DR) is a common diabetes complication that can lead to blindness through vision-threatening complications like clinically significant macular edema and proliferative retinopathy. Identifying eyes at risk of progression using non-invasive methods could help develop targeted therapies to halt diabetic retinal [...] Read more.
Background/Objectives: Diabetic retinopathy (DR) is a common diabetes complication that can lead to blindness through vision-threatening complications like clinically significant macular edema and proliferative retinopathy. Identifying eyes at risk of progression using non-invasive methods could help develop targeted therapies to halt diabetic retinal disease progression. Methods: A set of 82 imaging and systemic features was used to characterize the progression of nonproliferative diabetic retinopathy (NPDR). These features include baseline measurements (static features) and those capturing the temporal dynamic behavior of these static features within one year (dynamic features). Interpretable models were trained to distinguish between eyes with Early Treatment Diabetic Retinopathy Study (ETDRS) level 35 and eyes with ETDRS levels 43–47. The data used in this research were collected from 109 diabetic type 2 patients (67.26 ± 2.70 years; diabetes duration 19.6 ± 7.26 years) and acquired over 2 years. Results: The characterization of the data indicates that NPDR progresses from an initial stage of hypoperfusion to a hyperperfusion response. The performance of the classification model using static features achieved an area under the curve (AUC) of the receiver operating characteristics equal to 0.84 ± 0.07, while the model using both static and dynamic features achieved an AUC of 0.91 ± 0.05. Conclusion: NPDR progresses through an initial hypoperfusion stage followed by a hyperperfusion response. Characterizing and automatically identifying this disease progression stage is valuable and necessary. The results indicate that achieving this goal is feasible, paving the way for the improved evaluation of progression risk and the development of better-targeted therapies to prevent vision-threatening complications. Full article
(This article belongs to the Special Issue Pathophysiology of Retinopathy in Precision Medicine Era)
19 pages, 3135 KiB  
Article
Magnetic Resonance Imaging-Based Monitoring of the Accumulation of Polyethylene Terephthalate Nanoplastics
by Narmin Bashirova, Erik Butenschön, David Poppitz, Henrik Gaß, Marcus Halik, Doreen Dentel, Christoph Tegenkamp, Joerg Matysik and A. Alia
Molecules 2024, 29(18), 4380; https://doi.org/10.3390/molecules29184380 (registering DOI) - 14 Sep 2024
Viewed by 208
Abstract
Polyethylene terephthalate (PET) is one of the most produced plastic materials in the world. The emergence of microplastics and nanoplastics (MPs/NPs) as a significant environmental contaminant has become a matter of increasing concern. While the toxicological effects of PET NPs have been widely [...] Read more.
Polyethylene terephthalate (PET) is one of the most produced plastic materials in the world. The emergence of microplastics and nanoplastics (MPs/NPs) as a significant environmental contaminant has become a matter of increasing concern. While the toxicological effects of PET NPs have been widely researched, there is a lack of methodologies for studying their accumulation. The present study introduces a novel method to monitor the distribution of PET NPs in germinating wheat (Triticum aestivum L.) seeds. This involves the functionalization of superparamagnetic iron oxide nanoparticles (SPIONs) with PET NPs (PET–fSPIONs) coupled with magnetic resonance microimaging (µMRI) to provide insight into their distribution within the seed. The present study has demonstrated that PET–fSPIONs accumulate in specific regions of germinating wheat seeds, including the shoot apical meristem, the radicle, the coleoptile, the plumule, and the scutellum. Furthermore, the accumulation of PET–fSPIONs has been shown to exert a discernible effect on spin–spin relaxation (T2), as observed via MRI and quantitative T2 relaxation time analysis. The accumulation of PET NPs in embryo regions was also confirmed by SEM. Diffusion-weighted magnetic resonance imaging (DW-MRI) and non-invasive chemical shift imaging analyses demonstrated that PET NPs resulted in restricted diffusion within the highlighted areas, as well as an impact on lipid content. Our study reveals that using µMRI with fSPIONs provides a non-invasive method to monitor the biodistribution of PET nanoparticles in wheat seeds. Additionally, it offers valuable insights into the microstructural interactions of PET. Full article
20 pages, 833 KiB  
Review
The Neuroanatomy of Induced Pluripotent Stem Cells: In Vitro Models of Subcortical Nuclei in Neurodegenerative Disorders
by Alessandro Galgani, Marco Scotto and Filippo S. Giorgi
Curr. Issues Mol. Biol. 2024, 46(9), 10180-10199; https://doi.org/10.3390/cimb46090607 (registering DOI) - 14 Sep 2024
Viewed by 183
Abstract
Neuromodulatory subcortical systems (NSSs) are monoaminergic and cholinergic neuronal groups that are markedly and precociously involved in the pathogenesis of many neurodegenerative disorders (NDDs), including Parkinson’s and Alzheimer’s diseases. In humans, although many tools have been developed to infer information on these nuclei, [...] Read more.
Neuromodulatory subcortical systems (NSSs) are monoaminergic and cholinergic neuronal groups that are markedly and precociously involved in the pathogenesis of many neurodegenerative disorders (NDDs), including Parkinson’s and Alzheimer’s diseases. In humans, although many tools have been developed to infer information on these nuclei, encompassing neuroimaging and neurophysiological methods, a detailed and specific direct evaluation of their cellular features in vivo has been difficult to obtain until recent years. The development of induced pluripotent stem cell (iPSC) models has allowed research to deeply delve into the cellular and molecular biology of NSS neurons. In fact, iPSCs can be produced easily and non-invasively from patients’ fibroblasts or circulating blood monocytes, by de-differentiating those cells using specific protocols, and then be re-differentiated towards neural phenotypes, which may reproduce the specific features of the correspondent brain neurons (including NSS ones) from the same patient. In this review, we summarized findings obtained in the field of NDDs using iPSCs, with the aim to understand how reliably these might represent in vitro models of NSS. We found that most of the current literature in the field of iPSCs and NSSs in NDDs has focused on midbrain dopaminergic neurons in Parkinson’s disease, providing interesting results on cellular pathophysiology and even leading to the first human autologous transplantation. Differentiation protocols for noradrenergic, cholinergic, and serotoninergic neurons have also been recently defined and published. Thus, it might be expected that in the near future, this approach could extend to other NSSs and other NDDs. Full article
(This article belongs to the Special Issue Latest Review Papers in Molecular Biology 2024)
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<p>A schematic synthesis of NSS iPCS differentiation protocols. Starting from human somatic cells, either fibroblast or PBMC, a quite standardized reprogramming protocol is applied. Neural induction is obtained by inhibiting SMAD signaling and alternatively enhancing SHH and/or WNT pathways. Specific NSS phenotypes are then developed using standardized approaches, requiring specific growth factors, which are listed sequentially next to each arrow that connects the neural phenotype to the NSS phenotype. Abbreviations. AA—ascorbic acid; BDNF—brain-derived neurotrophic factor; BMP9—bone morphogenetic protein 9; c-MYC—myelocytomatosis oncogene; DAPT—N-[N-(3,5-difluorophenyl acetyl)-L-alanyl]-S-phenylglycine t-butyl ester; dbcAMP—dibutyryl cyclic AMP; FGF8—fibroblastic growth factor 8; GDNF—glial-derived neurotrophic factor; IGF-1—insulin growth factor 1; KLF4—Kruppel-like factor 4; NGF—nerve growth factor; OCT3/4—transcription factor POU domain class 5 transcription factor 1 (OCT3/4); SHH—sonic hedgehog; SOX2—sex-determining region Y-box2; TGFβ—transforming growth factor β.</p>
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20 pages, 3457 KiB  
Article
Non-Invasive Endometrial Cancer Screening through Urinary Fluorescent Metabolome Profile Monitoring and Machine Learning Algorithms
by Monika Švecová, Katarína Dubayová, Anna Birková, Peter Urdzík and Mária Mareková
Cancers 2024, 16(18), 3155; https://doi.org/10.3390/cancers16183155 (registering DOI) - 14 Sep 2024
Viewed by 199
Abstract
Endometrial cancer is becoming increasingly common, highlighting the need for improved diagnostic methods that are both effective and non-invasive. This study investigates the use of urinary fluorescence spectroscopy as a potential diagnostic tool for endometrial cancer. Urine samples were collected from endometrial cancer [...] Read more.
Endometrial cancer is becoming increasingly common, highlighting the need for improved diagnostic methods that are both effective and non-invasive. This study investigates the use of urinary fluorescence spectroscopy as a potential diagnostic tool for endometrial cancer. Urine samples were collected from endometrial cancer patients (n = 77), patients with benign uterine tumors (n = 23), and control gynecological patients attending regular checkups or follow-ups (n = 96). These samples were analyzed using synchronous fluorescence spectroscopy to measure the total fluorescent metabolome profile, and specific fluorescence ratios were created to differentiate between control, benign, and malignant samples. These spectral markers demonstrated potential clinical applicability with AUC as high as 80%. Partial Least Squares Discriminant Analysis (PLS-DA) was employed to reduce data dimensionality and enhance class separation. Additionally, machine learning models, including Random Forest (RF), Logistic Regression (LR), Support Vector Machine (SVM), and Stochastic Gradient Descent (SGD), were utilized to distinguish between controls and endometrial cancer patients. PLS-DA achieved an overall accuracy of 79% and an AUC of 90%. These promising results indicate that urinary fluorescence spectroscopy, combined with advanced machine learning models, has the potential to revolutionize endometrial cancer diagnostics, offering a rapid, accurate, and non-invasive alternative to current methods. Full article
(This article belongs to the Special Issue Image Analysis and Machine Learning in Cancers)
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<p>Semiquantitive strip analysis comparison of positive urine parameters.</p>
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<p>Urinary total fluorescent metabolome profiles (uTFMP) divided into fluorescent zones.</p>
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<p>Fluorescent urinary zones. Values are expressed as median ± interquartile range. **** indicates <span class="html-italic">p</span> &lt; 0.0001, *** indicates <span class="html-italic">p</span> &lt; 0.001, * <span class="html-italic">p</span> &lt; 0.05.</p>
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<p>Fluorescent ratios (<b>A</b>) Ratio Z4a/Z5. (<b>B</b>) Ratio Z6/Z7. Values are expressed as median ± interquartile range. **** indicates <span class="html-italic">p</span> &lt; 0.0001, *** indicates <span class="html-italic">p</span> &lt; 0.001, * <span class="html-italic">p</span> &lt; 0.05.</p>
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<p>Receiver operating characteristic curves (<b>A</b>) Ratio Z4a/Z5 (<b>B</b>) Ratio Z6/Z7.</p>
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<p>Partial Least Squares Discriminant Analysis (PLS-DA) (<b>A</b>) Train set between controls and malignant samples; (<b>B</b>) Test set between controls and malignant samples; (<b>C</b>) Train set between controls and benign samples; (<b>D</b>) Test set between controls and malignant samples; (<b>E</b>) ROC curve between controls and malignant samples; (<b>F</b>) ROC curve between controls and benign samples.</p>
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<p>ROC curves of built machine learning models (<b>A</b>) ML based on fluorescent zones and spectral ratios (<b>B</b>) ML based overall urinary total fluorescent metabolome profile.</p>
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<p>Confusion matrices for machine learning models: (<b>A</b>) fluorescent zones and spectral ratios. (<b>B</b>) overall urine total fluorescent metabolome profiles.</p>
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30 pages, 2672 KiB  
Systematic Review
The Diagnostic Potential of Non-Invasive Tools for Oral Cancer and Precancer: A Systematic Review
by Tania Vanessa Pierfelice, Emira D’Amico, Chiara Cinquini, Giovanna Iezzi, Camillo D’Arcangelo, Simonetta D’Ercole and Morena Petrini
Diagnostics 2024, 14(18), 2033; https://doi.org/10.3390/diagnostics14182033 - 13 Sep 2024
Viewed by 340
Abstract
Objectives: This systematic review aimed to analyse the published evidence for the use of non-invasive methods for the early detection of oral squamous cell carcinoma (OSCC) and oral potentially malignant disorders (OPMDs). Methods: The literature was systematically searched through several databases: PubMed, Cochrane [...] Read more.
Objectives: This systematic review aimed to analyse the published evidence for the use of non-invasive methods for the early detection of oral squamous cell carcinoma (OSCC) and oral potentially malignant disorders (OPMDs). Methods: The literature was systematically searched through several databases: PubMed, Cochrane Library, and Web of Science. Additional exploration was performed through cross-checks on the bibliographies of selected reviews. The inclusion criteria involved studies assessing the application of non-invasive tests on humans in the screening, diagnosis, or surveillance of OSCC or OPMDs and reporting sensitivity (SE) and specificity (SP). The Newcastle–Ottawa scale (NOS) was applied to assess the quality of the studies included. Results: The search strategy resulted in 8012 preliminary records. After a duplicate check, 116 titles remained. After abstract analysis, 70 papers remained. After full text analysis, only 54 of the 70 papers fit the inclusion criteria (28 were original articles and 26 were reviews). Those 26 reviews were used to manually search for further original articles. From this last search, 33 original articles were found. Thus, a total of 61 original studies were included and investigated. Findings from this systematic review indicate useful information, such as a description of the mechanisms, ease of use, limitations, and SE and SP values, to drive the choice of the optimal minimally invasive method to be utilized as an adjunctive tool to examine the suspicious lesions. Conclusions: Each of the analysed tools can be improved or implemented, considering their high SE and low SP. Despite advancements, incisional biopsy continues to be the gold standard for the definitive diagnosis of oral cancer and precancerous lesions. Further research and development are essential to improving the sensitivity, specificity, and reliability of non-invasive tools for widespread clinical application. Full article
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<p>Flow-chart diagram for the selection of the 61 studies included in the present analysis, according to “The PRISMA 2020 statement: an updated guideline for reporting systematic reviews.” The document can be accessed at the following link: <a href="https://www.prisma-statement.org/prisma-2020-flow-diagram" target="_blank">https://www.prisma-statement.org/prisma-2020-flow-diagram</a> (accessed on 5 August 2024).</p>
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<p>Illustration of non-invasive tools for the diagnosis of oral cancer and precancer, grouped by their class. Created with BioRender.com and Microsoft(R) PowerPointR for Microsoft 365 MSO (Version 2406).</p>
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<p>Sensitivity with the relative standard deviation of non-invasive visual diagnostic tools. This graph has been built including values reported in each study. The mean and standard deviations were then calculated.</p>
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<p>Specificity with the relative standard deviation of non-invasive visual diagnostic tools. This graph has been built including the values reported in each study. The mean and standard deviations were then calculated.</p>
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11 pages, 2254 KiB  
Article
Tracking Varroa Parasitism Using Handheld Infrared Cameras: Is Eusocial Fever the Key?
by Tamás Sipos, Szilvia Orsi-Gibicsár, Tamás Schieszl, Tamás Donkó, Zsombor Zakk, Sándor Farkas, Antal Binder and Sándor Keszthelyi
Insects 2024, 15(9), 693; https://doi.org/10.3390/insects15090693 - 13 Sep 2024
Viewed by 184
Abstract
The Varroa destructor is the most significant bee parasite and the greatest threat to bee health all around the world. Due to its hidden lifestyle, detection within the brood cell is only possible through invasive techniques. Enhancing detection methods is essential for advancing [...] Read more.
The Varroa destructor is the most significant bee parasite and the greatest threat to bee health all around the world. Due to its hidden lifestyle, detection within the brood cell is only possible through invasive techniques. Enhancing detection methods is essential for advancing research on population dynamics, spread, selection efforts, and control methodologies against the mite. In our study, we employed infrared imaging to measure the thermal differences in parasite and intact Apis mellifera worker broods. Experiments were conducted over two years at the MATE Kaposvár Campus in Hungary involving five beehives in 2022 and five beehives in 2023. A FLIR E5-XT WIFI handheld infrared camera was used to create a heat map of capped brood frames. Our results indicate that the resolution of these cameras is sufficient to provide detailed IR images of a bee colony, making them suitable to detect temperature differences in intact and Varroa parasitized capped brood cells. Mite parasitism causes a time-dependent and sustained temperature increase in developing bee pupae, observable regardless of mite number. Our work demonstrates two different heating patterns: hotspot heating and heating cells that are responsible for the elevated temperature of the Varroa-infested cells as a social fever response by the worker bees. Based on our results, future research combined with AI-based image evaluation software could offer beekeepers and researchers practical and valuable tools for high-throughput, non-invasive Varroa detection in the field. Full article
(This article belongs to the Section Insect Pest and Vector Management)
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<p>Plots of the relative abundance of mites in dissected brood cells over two years revealed differing trends.</p>
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<p>Thermal images of the same hive and frame captured at different time points ((<b>A1</b>) 23.10.14; (<b>A2</b>) 23.10.15), along with pixel intensity histograms (<b>B1</b>,<b>B2</b>) generated from digital image processing.</p>
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<p>Thermal map of brood with capped larvae (marked white hexagons), pre-pupae (scattered white hexagons), and older pupae (black hexagons).</p>
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<p>The two most common forms of elevated temperatures caused by Varroa mite. (<b>I.</b>) parasitized cell next to a heating cell; (<b>II.</b>) A hotspot pattern with the mite-infested brood cell in the center; black hexagon indicates intact; red hexagon indicates parasitized cells.</p>
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<p>Temperature distribution of the surface of intact and parasitized brood cells as a function of different numbers of Varroa mites (<span class="html-italic">n</span> = 508).</p>
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24 pages, 2905 KiB  
Review
Potential for Resveratrol to Combine with Hydrogel for Photodynamic Therapy against Bacteria and Cancer—A Review
by Siu Kan Law, Cris Wai Ching Liu, Christy Wing Sum Tong and Dawn Ching Tung Au
Biomedicines 2024, 12(9), 2095; https://doi.org/10.3390/biomedicines12092095 - 13 Sep 2024
Viewed by 328
Abstract
Bacterial infections and cancers are important issues in public health around the world. Currently, Western medicine is the most suitable approach when dealing with these issues. “Antibiotics” and “Corticosteroids” are the Western medicines used for bacterial infection. “Chemotherapy drugs”, “surgery”, and “radiotherapy” are [...] Read more.
Bacterial infections and cancers are important issues in public health around the world. Currently, Western medicine is the most suitable approach when dealing with these issues. “Antibiotics” and “Corticosteroids” are the Western medicines used for bacterial infection. “Chemotherapy drugs”, “surgery”, and “radiotherapy” are common techniques used to treat cancer. These are conventional treatments with many side effects. PDT is a non-invasive and effective therapy for bacterial infection and cancer diseases. Methods: Nine electronic databases, namely WanFang Data, PubMed, Science Direct, Scopus, Web of Science, Springer Link, SciFinder, and China National Knowledge Infrastructure (CNKI), were searched to conduct this literature review, without any regard to language constraints. Studies focusing on the photodynamic actions of hydrogel and Resveratrol were included that evaluated the effect of PDT against bacteria and cancer. All eligible studies were analyzed and summarized in this review. Results: Resveratrol has antibacterial and anticancer effects. It can also act as PS in PDT or adjuvant but has some limitations. This is much better when combined with a hydrogel to enhance the effectiveness of PDT in the fight against bacteria and cancer. Conclusions: Resveratrol combined with hydrogel is possible for PDT treatment in bacteria and cancer. They are compatible and reinforce each other to increase the effectiveness of PDT. However, much more work is required, such as cytotoxicity safety assessments of the human body and further enhancing the effectiveness of PDT in different environments for future investigations. Full article
(This article belongs to the Special Issue Photodynamic Therapy (3rd Edition))
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<p>Crosslinking compounds of hydrogel: (<b>a</b>) Glutaraldehyde, (<b>b</b>) Formaldehyde, and (<b>c</b>) Epoxy.</p>
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<p>Synthetic diagram for the synthesis of a chitosan-based hydrogel with hydrogen peroxide of antimicrobial peptide against <span class="html-italic">Staphylococcus aureus</span>.</p>
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<p>Synthetic diagram for the synthesis of a curcumin-chrysin-alginate-chitosan hydrogel against breast (T47D) and lung cancers (A549).</p>
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<p>Synthetic diagram for the synthesis of a polyacrylamide hydrogel against <span class="html-italic">Staphylococcus aureus</span> and <span class="html-italic">Escherichia coli</span>.</p>
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<p>Synthetic diagram for the synthesis of a stimuli−responsive hydrogel for cancer treatment.</p>
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<p>Schematic diagram of the PDT Types I and II mechanisms.</p>
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<p>Chemical structures of (<b>a</b>) Pheophorbide a (Pa), (<b>b</b>) Hypocrellin B (HB), and (<b>c</b>) Curcumin (Cur).</p>
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<p>Chemical structures of (<b>a</b>) <span class="html-italic">trans</span>-Resveratrol, and (<b>b</b>) <span class="html-italic">cis</span>-Resveratrol.</p>
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<p><span class="html-italic">Trans</span>-Resveratrol photooxidation of ergosterol via a [4+2] cycloaddition.</p>
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<p>Synthetic diagram for the incorporation of Resveratrol–hydroxypropyl–β-cyclodextrin complexes into hydrogel formulation against bacteria.</p>
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<p>Synthetic diagram for the chitosan-based hydrogels containing dopamine-reduced graphene oxide and Resveratrol against breast cancer.</p>
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14 pages, 897 KiB  
Review
Exploring Hydrogel Nanoparticle Systems for Enhanced Ocular Drug Delivery
by Zohreh Arabpour, Majid Salehi, Seungwon An, Amirhossein Moghtader, Khandaker N. Anwar, Seyed Mahbod Baharnoori, Rohan Jaimin Shah, Farshad Abedi and Ali R. Djalilian
Gels 2024, 10(9), 589; https://doi.org/10.3390/gels10090589 - 13 Sep 2024
Viewed by 380
Abstract
Drug delivery to the ocular system is affected by anatomical factors like the corneal epithelium, blinking reflex, aqueous blood barrier, and retinal blood barrier, which lead to quick removal from the site and inefficient drug delivery. Developing a drug delivery mechanism that targets [...] Read more.
Drug delivery to the ocular system is affected by anatomical factors like the corneal epithelium, blinking reflex, aqueous blood barrier, and retinal blood barrier, which lead to quick removal from the site and inefficient drug delivery. Developing a drug delivery mechanism that targets specific eye tissue is a major hurdle for researchers. Our study examines the challenges of drug absorption in these pathways. Hydrogels have been researched as a suitable delivery method to overcome some obstacles. These are developed alone or in conjunction with other technologies, such as nanoparticles. Many polymer hydrogel nanoparticle systems utilizing both natural and synthetic polymers have been created and investigated; each has pros and cons. The complex release mechanism of encapsulated agents from hydrogel nanoparticles depends on three key factors: hydrogel matrix swelling, drug-matrix chemical interactions, and drug diffusion. This mechanism exists regardless of the type of polymer. This study provides an overview of the classification of hydrogels, release mechanisms, and the role of controlled release systems in pharmaceutical applications. Additionally, it highlights the integration of nanotechnology in ocular disease therapy, focusing on different types of nanoparticles, including nanosuspensions, nanoemulsions, and pharmaceutical nanoparticles. Finally, the review discusses current commercial formulations for ocular drug delivery and recent advancements in non-invasive techniques. The objective is to present a comprehensive overview of the possibilities for enhancing ocular medication delivery through hydrogel nanoparticle systems. Full article
(This article belongs to the Special Issue Designing Gels for Wound Dressing)
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<p>Depiction of the blood-aqueous barrier, which is composed of the ciliary body, Schlemm’s canal, and iris vessels, and the blood-retinal barrier, which is composed of the retinal pigment epithelium and the endothelial membrane of retinal vessels.</p>
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24 pages, 8434 KiB  
Article
Computational Modeling Approach to Profile Hemodynamical Behavior in a Healthy Aorta
by Ahmed M. Al-Jumaily, Mohammad Al-Rawi, Djelloul Belkacemi, Radu Andy Sascău, Cristian Stătescu, Florin-Emilian Țurcanu and Larisa Anghel
Bioengineering 2024, 11(9), 914; https://doi.org/10.3390/bioengineering11090914 - 12 Sep 2024
Viewed by 252
Abstract
Cardiovascular diseases (CVD) remain the leading cause of mortality among older adults. Early detection is critical as the prognosis for advanced-stage CVD is often poor. Consequently, non-invasive diagnostic tools that can assess hemodynamic function, particularly of the aorta, are essential. Computational fluid dynamics [...] Read more.
Cardiovascular diseases (CVD) remain the leading cause of mortality among older adults. Early detection is critical as the prognosis for advanced-stage CVD is often poor. Consequently, non-invasive diagnostic tools that can assess hemodynamic function, particularly of the aorta, are essential. Computational fluid dynamics (CFD) has emerged as a promising method for simulating cardiovascular dynamics efficiently and cost-effectively, using increasingly accessible computational resources. This study developed a CFD model to assess the aorta geometry using tetrahedral and polyhedral meshes. A healthy aorta was modeled with mesh sizes ranging from 0.2 to 1 mm. Key hemodynamic parameters, including blood pressure waveform, pressure difference, wall shear stress (WSS), and associated wall parameters like relative residence time (RRT), oscillatory shear index (OSI), and endothelial cell activation potential (ECAP) were evaluated. The performance of the CFD simulations, focusing on accuracy and processing time, was assessed to determine clinical viability. The CFD model demonstrated clinically acceptable results, achieving over 95% accuracy while reducing simulation time by up to 54%. The entire simulation process, from image construction to the post-processing of results, was completed in under 120 min. Both mesh types (tetrahedral and polyhedral) provided reliable outputs for hemodynamic analysis. This study provides a novel demonstration of the impact of mesh type in obtaining accurate hemodynamic data, quickly and efficiently, using CFD simulations for non-invasive aortic assessments. The method is particularly beneficial for routine check-ups, offering improved diagnostics for populations with limited healthcare access or higher cardiovascular disease risk. Full article
(This article belongs to the Section Biomechanics and Sports Medicine)
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<p>The current processes used for CFD simulation.</p>
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<p>(<b>a</b>) The aortic geometry showing the lateral and medial views with the boundary conditions and the computational domain; (<b>b</b>) the location of the points considered for investigation (adapted from [<a href="#B2-bioengineering-11-00914" class="html-bibr">2</a>]).</p>
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<p>The mesh for the inlet face shows the inflation used for (<b>a</b>) tetrahedral and (<b>b</b>) polyhedral meshes.</p>
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<p>(<b>a</b>) The systolic pressure values for the different meshes; (<b>b</b>) the diastolic pressure values for the different meshes.</p>
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<p>The computational fluid dynamics result was validated against the clinical data for the mesh element size of 0.2 mm for both polyhedral and tetrahedral meshes.</p>
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<p>The pressure waveforms at the aortic arch for the different meshes: (<b>a</b>) tetrahedral; (<b>b</b>) polyhedral; (<b>c</b>) the ΔP2 at the aortic arch, showing that the difference between the meshes is minimal; and (<b>d</b>) the normal central aortic pressure waveform.</p>
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<p>TAWSS for the different meshes to see the development of high contours for healthy aorta. (Tetrahedral = Tetra; polyhedral = Poly).</p>
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<p>The threshold values for the TAWSS for the different meshes (blue for values below the threshold of 5 Pa and red for values above 5 Pa) are used to visualize areas higher and lower than the threshold value. (Tetra = tetrahedral; Poly = polyhedral).</p>
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<p>The OSI for the different meshes to see the development of high contours for healthy aorta. (Tetrahedral = Tetra; polyhedral = Poly).</p>
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<p>The RRT for the different meshes to see the development of high contours for healthy aorta. (Tetrahedral = Tetra; polyhedral = Poly).</p>
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<p>The ECAP for the different meshes to see the development of high contours for healthy aorta. (Tetrahedral = Tetra; polyhedral = Poly).</p>
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<p>The TAWSS for the three-time steps (0.005, 0.001, and 0.0005 s) for 0.4 mm mesh element size: (<b>a</b>) polyhedral mesh; and (<b>b</b>) tetrahedral mesh.</p>
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<p>The OSI for the three-time steps (0.005, 0.001, and 0.0005 s) for 0.4 mm mesh element size: (<b>a</b>) polyhedral mesh; and (<b>b</b>) tetrahedral mesh.</p>
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<p>The RRT for the three-time steps (0.005, 0.001, and 0.0005 s) for 0.4 mm mesh element size: (<b>a</b>) polyhedral mesh; and (<b>b</b>) tetrahedral mesh.</p>
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<p>The ECAP for the three-time steps (0.005, 0.001, and 0.0005 s) for 0.4 mm mesh element size: (<b>a</b>) polyhedral mesh; and (<b>b</b>) tetrahedral mesh.</p>
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<p>The threshold values of OSI for the different meshes presented in this study illustrate the high and low mechanical shear oscillation WSS per cardiac cycle on the aortic wall. (Tetrahedral = Tetra; polyhedral = Poly).</p>
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<p>The threshold contours for the RRT for the different meshes illustrate the relative residence time based on the mechanical oscillation during a cardiac cycle and WSS values on the aortic wall. (Tetrahedral = Tetra; polyhedral = Poly).</p>
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<p>The threshold for the ECAP for the different meshes illustrates the degree of thrombogenic susceptibility of the endothelial cell to localize the possible location for high mechanical oscillation. (Tetrahedral = Tetra; polyhedral = Poly).</p>
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10 pages, 6522 KiB  
Article
Standard-Deviation-Based Adaptive Median Filter for Elimination of Batwing Effects in Step Microstructure Measurement Using Digital Holography
by Jiasi Wei, Junjie Wu and Chen Wang
Sensors 2024, 24(18), 5928; https://doi.org/10.3390/s24185928 - 12 Sep 2024
Viewed by 215
Abstract
Digital holography has transformative potential for the measurement of stacked-chip microstructures due to its non-invasive, single-shot, full-field characteristics. However, significant light scattering and diffraction at steep edges in step microstructures cause the batwing effect, leading to measurement errors. Herein, we propose a standard-deviation-based [...] Read more.
Digital holography has transformative potential for the measurement of stacked-chip microstructures due to its non-invasive, single-shot, full-field characteristics. However, significant light scattering and diffraction at steep edges in step microstructures cause the batwing effect, leading to measurement errors. Herein, we propose a standard-deviation-based adaptive median filter to eliminate batwing effects in step microstructure measurement using digital holography. The standard deviation determines the positions of the steps and the range of the batwing effect. During filtering, the filter window size varies: it adjusts according to the center’s position within the batwing effect range and reduces outside this range to prevent distortion in other regions. Filtering weights are set to maintain information integrity while using larger filter windows. Experiments on the Standard Resolution Target USAF 1951 and the standard step height target show that our method successfully eliminates batwings while preserving the integrity of the remaining profile. Full article
(This article belongs to the Special Issue Precision Optical Metrology and Smart Sensing)
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<p>Digital holography system for measurement of microstructures.</p>
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<p>The optical configuration of the developed measurement system.</p>
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<p>Photograph of the Standard Resolution Target USAF 1951: (<b>a</b>) the whole view; (<b>b</b>) the measurement area.</p>
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<p>Areal topography of the measurement area of the resolution target before filtration: (<b>a</b>) 45-degree view; (<b>b</b>) front view.</p>
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<p>Areal topography after filtration: (<b>a</b>) 45-degree view; (<b>b</b>) front view.</p>
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<p>Comparison of the 2D profiles before (in red) and after (in blue) filtration.</p>
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<p>NIM-provided standard: (<b>a</b>) photograph; (<b>b</b>) surface at 50X magnification captured by confocal microscopy, Zeiss LSM 710.</p>
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<p>Raw measurement results: (<b>a</b>) areal topography; (<b>b</b>) intensity image with the designated area for batwing elimination highlighted in the red square.</p>
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<p>Areal topography of the measurement area of the standard artifact before filtration: (<b>a</b>) 45-degree view; (<b>b</b>) top-down view.</p>
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<p>Areal topography of the measurement area of the standard artifact after filtration: (<b>a</b>) 45-degree view; (<b>b</b>) front view.</p>
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<p>Comparison of the 2D profiles before (in red) and after (in blue) filtration in Experiment 2.</p>
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