PURPOSE: Dual velocity encoding PC-MRI can produce spurious artifacts when using high ratios of velocity encoding values (VENCs), limiting its ability to generate high-quality images across a wide range of encoding velocities. This study aims to propose and compare dual-VENC correction methods for such artifacts. THEORY AND METHODS: Two denoising approaches based on spatiotemporal regularization are proposed and compared with a state-of-the-art method based on sign correction. Accuracy is assessed using simulated data from an aorta and brain aneurysm, as well as 8 two-dimensional (2D) PC-MRI ascending aorta datasets. Two temporal resolutions (30,60) ms and noise levels (9,12) dB are considered, with noise added to the complex magnetization. The error is evaluated with respect to the noise-free measurement in the synthetic case and to the unwrapped image without additional noise in the volunteer datasets. RESULTS: In all studied cases, the proposed methods are more accurate than the Sign Correction technique. Using simulated 2D+T data from the aorta (60 ms, 9 dB), the Dual-VENC (DV) error 0.82±0.07$$ 0.82\pm 0.07 $$ is reduced to: 0.66±0.04$$ 0.66\pm 0.04 $$ (Sign Correction); 0.34±0.04$$ 0.34\pm 0.04 $$ and 0.32±0.04$$ 0.32\pm 0.04 $$ (proposed techniques). The methods are found to be significantly different (p-value <0.05$$ <0.05 $$ ). Importantly, brain aneurysm data revealed that the Sign Correction method is not suitable, as it increases error when the flow is not unidirectional. All three methods improve the accuracy of in vivo data. CONCLUSION: The newly proposed methods outperform the Sign Correction method in improving dual-VENC PC-MRI images. Among them, the approach based on temporal differences has shown the highest accuracy.

• MeSH
• algoritmy * MeSH
• aorta * diagnostické zobrazování   MeSH
• artefakty * MeSH
• fantomy radiodiagnostické MeSH
• interpretace obrazu počítačem metody   MeSH
• intrakraniální aneurysma diagnostické zobrazování   MeSH
• lidé MeSH
• magnetická rezonanční tomografie * metody   MeSH
• mozek diagnostické zobrazování   MeSH
• počítačová simulace MeSH
• počítačové zpracování obrazu * metody   MeSH
• poměr signál - šum * MeSH
• reprodukovatelnost výsledků MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

This study presents a combined experimental and numerical investigation of fiber transport and deposition in a realistic model of the female respiratory tract, extending to the seventh generation of branching. Numerical simulations were performed using the Euler-Lagrange Euler-Rotation (ELER) method, an efficient alternative to conventional Finite Volume Methods that benefits from explicit formulation and vast scalability, enabling fast parallelization on high-performance clusters. The ELER method was coupled with the Lattice Boltzmann Method (LBM) to simulate fiber dynamics under a realistic inspiratory flow profile. Experimental validation was conducted using an identical physical airway replica. The results demonstrated good agreement between simulations and experiments in the upper airways and trachea, with some discrepancies in the bifurcations, likely owing to the challenges of modeling complex turbulent flow with ELER. This method is more accurate than corresponding effective diameter simulations. Deposition patterns were analyzed as a function of fiber dimensions, revealing higher accuracy of the ELER method for smaller particles and confirming the tendency of higher aspect ratio fibers to penetrate deeper into the lungs. The orientation-dependent deposition mechanism was deployed, underscoring the importance of solving the actual orientations of the fibers. While advancing our understanding of fiber transport in female airways, the findings also reveal limitations in current numerical techniques, particularly in bifurcations. This study emphasizes the distinct behavior of fibrous versus spherical particles, with fibers exhibiting a greater propensity to reach deeper lung regions, which has significant implications for inhalation toxicology and drug delivery.

• MeSH
• aplikace inhalační MeSH
• biologické modely * MeSH
• dýchací soustava * MeSH
• lidé MeSH
• plíce MeSH
• počítačová simulace MeSH
• trachea * fyziologie   MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Thyroid hormones (TH) are essential for vertebrate development, growth, and metabolism. The increasing prevalence of anthropogenic chemicals with TH-disrupting potential highlights the urgent need for advanced methods to assess their impact on TH homeostasis. Inhibition of the sodium-iodide symporter (NIS) has been identified as a key molecular initiating event disrupting the TH system across species, with significant relevance for diagnostic and therapeutic applications in various carcinomas. This study presents in vitro bioassays for evaluating the effects of compounds on iodide uptake into cells, a critical step in TH production mediated by NIS. Two novel stably transfected human cell lines overexpressing human NIS were employed along with a rat thyroid cell model FRTL-5, using colorimetric Sandell-Kolthoff (SK) reaction for iodide detection. The results from 23 model compounds demonstrate comparability across various in vitro models and radioactivity-based assays. To enhance physiological relevance, an external biotransformation system (BTS) was integrated and optimized for live-cell compatibility without inducing cytotoxicity or interfering with the assay. Compounds identified as NIS inhibitors were evaluated using the BTS-augmented assay, which revealed that metabolic activity mitigated the inhibitory effects of some chemicals. The augmented assay exhibited strong concordance with in vivo and in silico biotransformation data. Protein sequence alignment confirmed high conservation of NIS functional domains across vertebrates, reinforcing the cross-species applicability of the findings. The SK-based NIS assay, with optional BTS integration, represents a sensitive, robust, and high-throughput amendable alternative to radioactivity-based methods, for characterizing the impacts of individual compounds and complex environmental mixtures on TH homeostasis.

• MeSH
• biotest metody   MeSH
• biotransformace MeSH
• buněčné linie MeSH
• endokrinní disruptory * toxicita   MeSH
• hormony štítné žlázy metabolismus   MeSH
• jodidy * metabolismus   MeSH
• krysa rodu rattus MeSH
• lidé MeSH
• štítná žláza metabolismus   účinky léků   cytologie   MeSH
• symportéry * antagonisté a inhibitory   metabolismus   genetika   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Integral membrane proteins carry out essential functions in the cell, and their activities are often modulated by specific protein-lipid interactions in the membrane. Here, we elucidate the intricate role of cardiolipin (CDL), a regulatory lipid, as a stabilizer of membrane proteins and their complexes. Using the in silico-designed model protein TMHC4_R (ROCKET) as a scaffold, we employ a combination of molecular dynamics simulations and native mass spectrometry to explore the protein features that facilitate preferential lipid interactions and mediate stabilization. We find that the spatial arrangement of positively charged residues as well as local conformational flexibility are factors that distinguish stabilizing from non-stabilizing CDL interactions. However, we also find that even in this controlled, artificial system, a clear-cut distinction between binding and stabilization is difficult to attain, revealing that overlapping lipid contacts can partially compensate for the effects of binding site mutations. Extending our insights to naturally occurring proteins, we identify a stabilizing CDL site within the E. coli rhomboid intramembrane protease GlpG and uncover its regulatory influence on enzyme substrate preference. In this work, we establish a framework for engineering functional lipid interactions, paving the way for the design of proteins with membrane-specific properties or functions.

• MeSH
• DNA vazebné proteiny MeSH
• endopeptidasy metabolismus   chemie   genetika   MeSH
• Escherichia coli metabolismus   genetika   MeSH
• kardiolipiny * metabolismus   chemie   MeSH
• membránové proteiny * metabolismus   chemie   genetika   MeSH
• proteinové inženýrství * MeSH
• proteiny z Escherichia coli * metabolismus   chemie   genetika   MeSH
• simulace molekulární dynamiky MeSH
• vazba proteinů MeSH
• Publikační typ
• časopisecké články MeSH

This paper presents an innovative mathematical model for assessing the dynamics and optimal control of Nipah virus (NiV) with imperfect vaccination. The model formulation considers transmissions through contaminated food and human-to-human contacts. It also incorporates the potential virus transmission through contact with a deceased body infected with NiV. Initially, the NiV model is assessed theoretically, identifying three distinct equilibrium states: the NiV-endemic equilibrium state, the NiV-free equilibrium state, and the equilibrium state involving infected flying foxes. Furthermore, the stability results of the model in the case of constant controls are thoroughly analyzed at the NiV-free equilibrium. Some of the parameters of the model are estimated based on the infected cases documented in Bangladesh from 2001 to 2017. We further perform sensitivity analysis to determine the most influential parameters and formulate effective time-dependent controls. Numerical simulations indicate the optimal course of action for eradicating the disease and provide a comparative analysis of controlling the infection under constant and time-varying interventions. The simulation confirms that the implementation of time-varying interventions is effective in minimizing disease incidence.

• MeSH
• infekce viry z rodu Henipavirus * přenos   prevence a kontrola   epidemiologie   MeSH
• lidé MeSH
• počítačová simulace MeSH
• teoretické modely MeSH
• vakcinace * MeSH
• virus Nipah * imunologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Bangladéš MeSH

Parkinson's disease (PD) is one of the most common progressive neurodegenerative pathologies that leads to dopaminergic deficiency and motor manifestations. Alpha-synuclein aggregation is a characteristic hallmark of PD pathogenesis. These aggregates facilitate the formation of Lewy bodies and degeneration. The epidemiological evidence demonstrates a definitive association of diabetes with PD risk. Considering this, many antidiabetic agents such as GLP-1 agonists and DPP-4 inhibitors are being explored as alternative PD therapeutics. This study evaluated the neuroprotective effect of the DPP-4 inhibitor sitagliptin mediated by the PI3K/AKT and Nrf2 pathways in PD models. In silico studies were conducted to determine the binding affinity, stability, and ADMET properties of DPP-4 inhibitors with target proteins. Sitagliptin (15 mg/kg p.o.) was administered in rotenone (30 mg/kg p.o. for 28 days)-induced and MPTP/P (25 mg/kg i.p. MPTP and 100 mg/kg probenecid i.p. twice a week for 5 weeks)-induced PD mouse (C57/BL6) models. Neurobehavioral assessments were carried out throughout the study. Biochemical (GSH, MDA), molecular estimations (AKT, Nrf2, PI3K, GSK-3β, GLP1, CREB, BDNF, NF-κB, alpha-synuclein), histopathological studies, and immunohistochemistry were carried out at the end of the study. The in silico studies demonstrate better binding, stability, and ADMET profile of sitagliptin with both target proteins. Sitagliptin restored cognitive and motor deficits in both rotenone- and MPTP/P-induced mouse models. There was upregulation of PI3K, AKT, Nrf2, CREB, and BDNF levels and downregulation of GSK-3β, NF-κB, and alpha-synuclein levels in both models after treatment with sitagliptin. However, GLP1 levels were not significantly restored, indicating a GLP1-independent mechanism. It also restored histopathological alterations and TH+ neuronal loss induced by rotenone and MPTP/P. These findings demonstrate that sitagliptin exhibits neuroprotective action mediated by upregulation of the PI3K/AKT and Nrf2 pathways in rotenone and MPTP/P mouse models of PD.

• MeSH
• faktor 2 související s NF-E2 * metabolismus   MeSH
• fosfatidylinositol-3-kinasy metabolismus   MeSH
• inhibitory dipeptidylpeptidasy 4 * farmakologie   MeSH
• modely nemocí na zvířatech MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• neuroprotektivní látky * farmakologie   MeSH
• parkinsonské poruchy * metabolismus   farmakoterapie   MeSH
• protoonkogenní proteiny c-akt * metabolismus   MeSH
• rotenon MeSH
• signální transdukce účinky léků   MeSH
• sitagliptin fosfát * farmakologie   MeSH
• upregulace účinky léků   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

AIM: This study aimed to investigate the phytochemical composition of Psychotria montana extract (PME) and evaluate its inhibitory effects on MCF7 breast cancer cells. METHODS: The chemical composition of PME was analyzed using UPLC-QToF-MS. The effects of PME on cell proliferation were evaluated using the MTT assay. Flow cytometry was used for cell cycle and apoptosis analysis. The effects of PME on the transcription of cell cycle control genes were assessed using real-time PCR. RESULTS: UPLC-QToF-MS analysis revealed major compounds of PME, including terpenoids and flavonoids, with the potential to inhibit proliferation, migration, and induce apoptosis in MCF7 cancer cells. PME effectively suppressed MCF7 cell proliferation under 2D culture, with a low IC50 value of 34.7 μg/ml. PME also hindered cell migration (p < 0.01) and reduced spheroid number (p < 0.001) and size (p < 0.001) in serum-free 3D culture. Apoptosis analysis via nuclear staining with DAPI and flow cytometry revealed an increase in the number of apoptotic cells after PME treatment (p < 0.001). Additionally, the PME induced cell cycle arrest at the G0/G1 phase (p < 0.05). PME altered the expression of cell cycle control genes (cyclins and CDKs) as well as cancer suppressor genes including p16, p27, and p53 at the transcriptional level (mRNA). The results of molecular docking suggest that the compounds present in PME exhibit a high binding affinity for CDK3, CDK4, CDK6, and CDK8 proteins, which are essential regulators of the cell cycle. CONCLUSION: Psychotria montana has the potential to inhibit cancer cells by inducing apoptosis and halting the cell cycle of MCF7 breast cancer cells.

• MeSH
• apoptóza * účinky léků   MeSH
• buněčný cyklus účinky léků   MeSH
• fytogenní protinádorové látky farmakologie   chemie   MeSH
• lidé MeSH
• MFC-7 buňky MeSH
• nádory prsu * farmakoterapie   patologie   genetika   metabolismus   MeSH
• počítačová simulace MeSH
• pohyb buněk účinky léků   MeSH
• proliferace buněk * účinky léků   MeSH
• Psychotria * chemie   MeSH
• rostlinné extrakty * farmakologie   chemie   MeSH
• simulace molekulového dockingu MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

To evaluate the clinical performance and safety of the ONIRY system for obstetric anal sphincter injuries (OASI) detection versus three-dimensional endoanal ultrasound (EAUS). A prospective, comparative, multicentre, international study. Poland, Czechia, Slovakia, and Spain. 152 women between the first moments up to 8 weeks after vaginal delivery. Participants underwent EAUS and were allocated to groups based on OASIS classification: A (no perineal tear), B (1st or 2nd degree tear), or C (3rd or 4th degree, anal sphincters affected). Electric impedance was measured in the anal canal using the ONIRY system. The primary endpoint was the diagnostic outcome of impedance spectroscopy versus EAUS. Adverse events were collected. Part II involved in silico modelling and 10-time 10-fold cross-validation for automated analysis. Accuracy, sensitivity, and specificity. 30 women were allocated to group A, 61 to group B, and 61 to group C. The diagnostic outcome was determined for 147 participants. The accuracy, sensitivity, and specificity of the ML-assisted impedance spectroscopy were 87.0 ± 0.5%, 90.6 ± 2.0%, and 84.6 ± 1.9%, respectively, compared with EAUS. After data cleaning, the performance metrics of the proposed final ML model for ONIRY were: 90.0 ± 0.4%, 90.0 ± 1.2%, and 90.0 ± 0.7%, respectively. No adverse device effects or deficiencies were observed. By enabling early identification of sphincter injuries, ML-assisted impedance spectroscopy facilitates timely diagnosis and intervention, potentially reducing long-term complications such as faecal incontinence. Its rapid, bedside application in obstetric settings supports immediate postpartum care, complementing digital rectal examination and optimizing clinical decision-making.

• MeSH
• anální kanál * zranění   diagnostické zobrazování   MeSH
• dospělí MeSH
• impedanční spektroskopie * metody   MeSH
• komplikace porodu diagnóza   diagnostické zobrazování   MeSH
• lidé MeSH
• prospektivní studie MeSH
• strojové učení * MeSH
• těhotenství MeSH
• vedení porodu * škodlivé účinky   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• srovnávací studie MeSH

Permeability is an important molecular property in drug discovery, as it co-determines pharmacokinetics whenever a drug crosses the phospholipid bilayer, e.g., into the cell, in the gastrointestinal tract, or across the blood-brain barrier. Many methods for the determination of permeability have been developed, including cell line assays (CACO-2 and MDCK), cell-free model systems like parallel artificial membrane permeability assay (PAMPA) mimicking, e.g., gastrointestinal epithelia or the skin, as well as the black lipid membrane (BLM) and submicrometer liposomes. Furthermore, many in silico approaches have been developed for permeability prediction: meta-analysis of publicly available databases for permeability data (MolMeDB and ChEMBL) was performed to establish their usability. Four experimental and two computational methods were evaluated. It was shown that repeatability of the reported permeability measurement is not great even for the same method. For the PAMPA method, two different permeabilities are reported: intrinsic and apparent. They can vary in degrees of magnitude; thus, we suggest being extra cautious using literature data on permeability. When we compared data for the same molecules using different methods, the best agreement was between cell-based methods and between BLM and computational methods. Existence of unstirred water layer (UWL) permeability limits the data agreement between cell-based methods (and apparent PAMPA) with data that are not limited by UWL permeability (computational methods, BLM, intrinsic PAMPA). Therefore, different methods have different limitations. Cell-based methods provide results only in a small range of permeabilities (-8 to -4 in cm/s), and computational methods can predict a wider range of permeabilities beyond physical limitations, but their precision is therefore limited. BLM with liposomes can be used for both fast and slow permeating molecules, but its usage is more complicated than standard transwell techniques. To sum up, when working with in-house measured or published permeability data, we recommend caution in interpreting and combining them.

• MeSH
• buňky MDCK MeSH
• Caco-2 buňky MeSH
• hematoencefalická bariéra metabolismus   MeSH
• lidé MeSH
• liposomy * chemie   MeSH
• membrány umělé MeSH
• permeabilita buněčné membrány fyziologie   MeSH
• permeabilita * MeSH
• psi MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• psi MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• metaanalýza MeSH

PURPOSE: Focused ultrasound-induced blood-brain barrier (BBB) opening is a promising method for neurotherapeutic delivery. The standard for quantifying induced BBB permeability is the Ktrans$$ {K}^{\mathrm{trans}} $$ parameter, which reflects both permeability and plasma flow. The influence of plasma flow can be eliminated by estimating the PS parameter. However, this parameter has been largely unexplored in this application. This study aims to compare permeability estimates based on Ktrans$$ {K}^{\mathrm{trans}} $$ and PS in focused ultrasound-induced BBB opening experiments. METHODS: We used the extended Tofts model (ETM) and the two-compartment exchange model (2CXM) to estimate Ktrans$$ {K}^{\mathrm{trans}} $$ and PS parameters, respectively. Permeability estimates were compared using simulated concentration curves, simulated DCE-MRI data, and real datasets. We explored the influence of spatially-regularized model fitting on the results. RESULTS: For opened BBB, Ktrans$$ {K}^{\mathrm{trans}} $$ was minimally influenced by plasma flow under the tested conditions. However, fitting the ETM often introduced outliers in Ktrans$$ {K}^{\mathrm{trans}} $$ estimates in regions with closed BBB. The 2CXM outperformed the ETM at high signal-to-noise ratios, but its higher complexity led to lower precision at low signal-to-noise ratios. Both these issues were successfully compensated by spatially-regularized model fitting. CONCLUSION: Both Ktrans$$ {K}^{\mathrm{trans}} $$ and PS seem to be eligible options for the quantification of BBB opening, and the correct choice depends on the specifics of the acquired DCE-MRI data. Additionally, spatial regularization has demonstrated its importance in enhancing the accuracy and reproducibility of results for both models.

• MeSH
• hematoencefalická bariéra * diagnostické zobrazování   metabolismus   účinky záření   MeSH
• kontrastní látky MeSH
• lidé MeSH
• magnetická rezonanční tomografie * metody   MeSH
• mozek diagnostické zobrazování   MeSH
• permeabilita MeSH
• počítačová simulace MeSH
• počítačové zpracování obrazu metody   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH