Phase Image Analysis Research Articles

Application of texture signatures based on multiparameter-magnetic resonance imaging for predicting microvascular invasion in hepatocellular carcinoma: Retrospective study.

Despite continuous changes in treatment methods, the survival rate for advanced hepatocellular carcinoma (HCC) patients remains low, highlighting the importance of diagnostic methods for HCC. To explore the efficacy of texture analysis based on multi-parametric magnetic resonance (MR) imaging (MRI) in predicting microvascular invasion (MVI) in preoperative HCC. This study included 105 patients with pathologically confirmed HCC, categorized into MVI-positive and MVI-negative groups. We employed Original Data Analysis, Principal Component Analysis, Linear Discriminant Analysis (LDA), and Non-LDA (NDA) for texture analysis using multi-parametric MR images to predict preoperative MVI. The effectiveness of texture analysis was determined using the B11 program of the MaZda4.6 software, with results expressed as the misjudgment rate (MCR). Texture analysis using multi-parametric MRI, particularly the MI + PA + F dimensionality reduction method combined with NDA discrimination, demonstrated the most effective prediction of MVI in HCC. Prediction accuracy in the pulse and equilibrium phases was 83.81%. MCRs for the combination of T2-weighted imaging (T2WI), arterial phase, portal venous phase, and equilibrium phase were 22.86%, 16.19%, 20.95%, and 20.95%, respectively. The area under the curve for predicting MVI positivity was 0.844, with a sensitivity of 77.19% and specificity of 91.67%. Texture analysis of arterial phase images demonstrated superior predictive efficacy for MVI in HCC compared to T2WI, portal venous, and equilibrium phases. This study provides an objective, non-invasive method for preoperative prediction of MVI, offering a theoretical foundation for the selection of clinical therapy.

A-144 Three-wavelength Polarization Imaging Method for the Analysis of Individual Human Blood Cells With Dye-Enhanced Dispersion of Dilution Buffer

Abstract Background Performing basic hematology analysis in a near-patient setting enables more rapid clinical decision making in the process of diagnosis. Traditional blood analyzers in central labs use a complex combination of sensing principles and chemical modification of the sample to derive the necessary parameters for a complete blood count (CBC). To reduce cost and maintenance, varying approaches have been employed to determine a CBC with a single-step measurement technique. One common option is the use of optical microscopy to deliver highly reliable results, examples are fluorescence microscopy, digital holographic microscopy, or spatial light interference microscopy. However, most of these technologies lack a proper determination of cellular-level RBC parameters. Therefore, a non-interferometric, quantitative-phase measurement technique was developed to derive relevant CBC parameters from a single measurement, comparable to a standard lab analyzer. Methods The optical setup employed by this method enables the parallel acquisition of brightfield and differential interference contrast (DIC) images by polarization-sensitive cameras. By using three cameras with individual optical filters, quantitative phase and absorption information can be calculated, which enables the determination of mean cellular volume (MCV), mean cellular hemoglobin (MCH), and mean cellular hemoglobin concentration (MCHC) for red blood cells (RBCs). The whole-blood sample is diluted in a buffer containing a non-cell-penetrating dye to enhance optical refraction contrast and therefore precision in the dependent calculated quantities. The sample is then introduced to a glass flow cell, and the cells are allowed to sediment to the bottom for imaging. Machine learning is applied to the derived images to classify unstained native white blood cells (WBCs) to yield a 5-part differential, which distinguishes between neutrophil, monocyte, lymphocyte, eosinophil and basophil. The algorithm is trained by imaging FACS-validated, purified WBC subgroups. All blood samples are measured on an ADVIA® 2120 Hematology System for control. Results A one-step, optical CBC hematology system based on quantitative phase and absorption image analysis was developed. The correlations for MCV and MCHC compared to a standard lab CBC analyzer were 0.77 and 0.84. The accuracy for the 5-part differential WBC classification was approximately 0.8. To enable a visual inspection of the classification results, a pseudo-colored image of each cell was generated and uploaded in a review tool. Conclusion With a more-refined, less-expensive optical setup, a high-quality CBC analyzer suitable for use at the point of care can be derived with the presented method. A possible simplification could be the use of low-cost but high-resolution Fourier ptychography microscopy (FPM) technology. Imaging of blood samples on a single-cell level offers the potential for the analysis of even more morphological parameters, for example, disease-related changes in the cell membrane. Also, the adhesion behavior of the WBCs in the glass flow cell could indicate cell activation status and therefore give information about infection processes. *Trademark disclaimer: “ADVIA, and all associated marks are trademarks of Siemens Healthcare Diagnostics, Inc. or its affiliates. All other trademarks and brands are the property of their respective owners.”

Возможности прижизненной визуализации клеток крови при стрессе для оценки состояния организма

Biological specimens are the most difficult to study as almost exclusively light elements are considered, a little visibility yielded and structures are sparsely distinguishable. In addition cell structures are easily damaged on any stage of microscopic exploration. The optimal solution is to study their phase changes using laser interference microscopy. The method is based on the analysis of refractive index of intracellular medium of cells with subsequent computer analysis and processing of phase images followed by three-dimensional reconstruction of the object. The obtained images are digitally recorded, and any point of view can be introduced for viewing. This work uses laser interference microscopy followed by 3D reconstruction of cell images to study blood cells: neutrophils and erythrocytes by 3D reconstruction of neutrophils have demonstrated changes of their functional activity under technological stress, while 3D reconstruction of erythrocytes revealed a violation of the normal discoidal cell shape. Interpretation of the obtained data indicates a restructuring of the cellular component of nonspecific resistance and deterioration of the oxygen transport function of erythrocytes under technological stress. Visualization of interference patterns of blood cells through 3D image processing allows obtaining n a vital analysis of cells, the technique that is not available for other methods of microscopy, in particular light microscopy, which is traditionally used as a prognostic method of the state of the body. This direction represents the most important condition for further development of works in the field of cell diagnostics. The obtained results prove the applicability of 3D reconstruction of cell images for bioscanning of technological stress.

Fabrication of Novel Polymer Composites from Leather Waste Fibers and Recycled Poly(Ethylene-Vinyl-Acetate) for Value-Added Products

This investigation was focused on evaluating the utilization of Leather-waste, i.e., “Leather Shavings”, to develop “Poly(ethylene-vinyl-acetate)” (EVA) based “polymer matrix composites”. Composites with the highest ratio of 1:1 were developed using a rolling-mill, which was then subjected to hot-press molding for value-added applications, notably in the “floor-covering”, “structural”, “footwear”, and “transportation domain”. The specimens were examined for evaluating the “physico-mechanical characteristics” such as, “Compressive and Tensile, strength, Abrasion-resistance, Density, tear-resistance, hardness, adhesion-strength, compression, and resilience, damping, and water absorption” as per standard advanced testing techniques. Raising the leather-fiber fraction in the composites culminated in considerable enhancement in “physico-mechanical characteristics” including “modulus”, and a decline in “tensile-strain” at “fracture-breakage”. The thermo-analytic methods, viz. TGA and DSC studies have evidenced that substantial enhancement of thermo-stability (up to 211.1–213.81 °C) has been observed in the newly developed PMCs. Additionally, the DSC study showed that solid leather fibers lose water at an endothermic transition temperature of around 100 °C, are thermo-stable at around 211 degrees centigrade, and begin to degrade at 332.56-degree centigrade for neat recycled EVA samples and begin to degrade collagen at 318.47-degree centigrade for “leather shavings/recycled EVA polymer composite samples”, respectively. Additionally, the “glass transition temperature” (Tg) of the manufactured composites was determined to be between −16 and 30 °C. Furthermore, SEM and EDAX analysis have been used to investigate the morphological characteristics of the developed composites. Micrograph outcomes have confirmed the excellent “uniformity, compatibility, stability and better-bonding” of leather-fibers within the base matrix. Additionally, the “Attenuated-total-reflection” (ATR-FTIR) was carried out to test the “physicochemical chemical-bonding”, “molecular-structure”, and “functional-groups” of the “base matrix”, and its “composites” further affirm the “recycled EVA matrix” contained additives remain within the polymeric-matrix. An “X-ray diffraction study” was also conducted to identify the “chemical-constituents” or “phases” involved throughout the “crystal-structures” of the base matrix and PMCs. Additionally, AFM analysis has also been utilized to explore the “interfacial adhesion properties” of mechanically tested specimens of fabricated polymeric composite surfaces, their “surface topography mapping”, and “phase-imaging analysis” of polymer composites that have leather-shavings fibers.

Fourier Phase Analysis of Dynamic Antral Contraction Scintigraphy: New Software, Reference Values, and Comparisons to Conventional Gastric Emptying.

Dynamic antral contraction scintigraphy (DACS) has been used to evaluate for gastric dysmotility by measuring antral contraction frequency and ejection fraction (EF). Fourier phase image analysis has the potential to assess gastric antral contractions for dyssynchrony as has been used for analyzing nuclear cardiology ventriculography (multigated acquisition studies) for cardiac dyssynchrony. The aims of this study were to determine whether Fourier phase analysis helps to characterize antral motility physiology, whether Fourier phase analysis correlates with conventional gastric emptying scintigraphy (GES), and which DACS parameters may aid in diagnosing gastric dysmotility, particularly delayed gastric emptying (GE). Methods: DACS and GES of healthy volunteers (n = 22) were compared with patients (n = 99) with symptoms of gastroparesis. New DACS Fourier phase analysis software was developed. Results: GE was delayed (n = 53) or normal (n = 46) in patients. There was a linear correlation between the time for the stomach to empty 50% of the meal and the percentage total proximal and distal in-phase antral pixels at 30 min (r = 0.37, P = 0.0001) and 60 min (r = 0.26, P = 0.007). In healthy volunteers, the mean proximal-to-distal ratio of in-phase antral pixels increased from 1.67 (30 min) to 2.65 (120 min) (P = 0.035), and EF increased from 23% (30 min) to 32% (120 min) (P = 0.022). Multivariable regressions of percentage total proximal and distal in-phase antral pixels (30 min) and EF (60 min) were the best predictors of abnormal GE (adjusted odds ratio, 3.30 [95% CI, 1.21-9.00] and 2.97 [95% CI, 1.08-8.21], respectively). Conclusion: This study used Fourier phase analysis to analyze DACS in healthy volunteers and patients with symptoms of gastroparesis. In addition to establishing reference values, new physiologic information on antral motility was obtained. In healthy volunteers, there was an increasing proximal-to-distal ratio of in-phase antral pixels and antral EF over time after meal ingestion. The percentage total proximal and distal in-phase antral pixels at both 30 and 60 min correlated well with GE values for the time for the stomach to empty 50% of the meal. For symptomatic patients, the percentage total proximal and distal in-phase antral pixels at 30 min and the EF at 60 min after meal ingestion correlated with delayed GE on conventional GES. Thus, Fourier phase analysis of DACS appears to have potential to further aid in diagnosing gastric dysmotility in GES.

The Near Infrared Imager and Slitless Spectrograph for JWST. V. Kernel Phase Imaging and Data Analysis

Kernel phase imaging (KPI) enables the direct detection of substellar companions and circumstellar dust close to and below the classical (Rayleigh) diffraction limit. The high-Strehl full pupil images provided by the James Webb Space Telescope (JWST) are ideal for application of the KPI technique. We present a kernel phase analysis of JWST NIRISS full pupil images taken during the instrument commissioning and compare the performance to closely related NIRISS aperture masking interferometry (AMI) observations. For this purpose, we develop and make publicly available the custom Kpi3Pipeline data reduction pipeline enabling the extraction of kernel phase observables from JWST images. The extracted observables are saved into a new and versatile kernel phase FITS file data exchange format. Furthermore, we present our new and publicly available fouriever toolkit which can be used to search for companions and derive detection limits from KPI, AMI, and long-baseline interferometry observations while accounting for correlated uncertainties in the model fitting process. Among the four KPI targets that were observed during NIRISS instrument commissioning, we discover a low-contrast (∼1:5) close-in (∼1 λ/D) companion candidate around CPD-66 562 and a new high-contrast (∼1:170) detection separated by ∼1.5 λ/D from 2MASS J062802.01-663738.0. The 5σ companion detection limits around the other two targets reach ∼6.5 mag at ∼200 mas and ∼7 mag at ∼400 mas. Comparing these limits to those obtained from the NIRISS AMI commissioning observations, we find that KPI and AMI perform similar in the same amount of observing time. Due to its 5.6 times higher throughput if compared to AMI, KPI is beneficial for observing faint targets and superior to AMI at separations ≳325 mas. At very small separations (≲100 mas) and between ∼250 and 325 mas, AMI slightly outperforms KPI which suffers from increased photon noise from the core and the first Airy ring of the point-spread function.

Carboxylated acrylonitrile butadiene-natural rubber latex blends with methyl methacrylate grafted natural rubber latex: mechanical properties and morphology.

Commercially available carboxylated acrylonitrile butadiene latex (XNBR) was physically blended with natural rubber latex (NR) at varying blend ratios to investigate its effect on the mechanical properties and morphology. Methyl methacrylate grafted natural rubber latex (MG) was added to the latex blends as a third polymer to study whether it could enhance the mechanical properties of the latex blend films. It was found that the tensile strength of the blend films irrespective of composition decreased when the two latexes were blended as compared to the virgin latex films. The modulus 300 decreased while the elongation at break and tear strength of the blend films increased gradually as the ratio of NR increased in the blend films. It was found that the MG did not enhance the mechanical properties of the XNBR/NR blend films under the current experimental condition. AFM phase imaging analysis revealed enhanced polymer distribution and evidence of NR-MG-XNBR interactions.

Noninvasive Nanodiamond Skin Permeation Profiling Using a Phase Analysis Method: Ex Vivo Experiments.

Carbon-based nanoparticles (NPs) are widely used in nanotechnology. Among them, nanodiamonds (NDs) are suitable for biotechnology and are especially interesting for skin delivery and topical treatments. However, noninvasive detection of NDs within the different skin layers or analyzing their penetration ability is complicated due to the turbid nature of the tissue. The iterative multiplane optical properties extraction (IMOPE) technique detects differences in the optical properties of the measured item by a phase-image analysis method. The phase image is reconstructed by the multiplane Gerchberg-Saxton algorithm. This technique, traditionally, detects differences in the reduced scattering coefficients. Here, however, due to the actual size of the NDs, the IMOPE technique's detection relies on absorption analysis rather than relying on scattering events. In this paper, we use the IMOPE technique to detect the presence of the NDs within tissue-like phantoms. In addition, we perform ex vivo pigskin experiments to estimate the penetration of the NDs to the different skin layers and show that their presence reduces at deeper layers. The significance signal of the NDs within the epidermis, dermis, and fat layers gradually reduces, with t test significance values that are smaller than 10-4, 10-3, and 10-2, respectively. The IMOPE results are corroborated by TEM results and Franz-cell experiments. These results confirm that the IMOPE profiled the skin-permeation of the NDs noninvasively.

Diagnosis of cardiac amyloid transthyretin (ATTR) amyloidosis by early (soft tissue) phase [99mTc]Tc-DPD whole body scan: comparison with late (bone) phase imaging.

Although expert consensus recommendations suggest 2-3h as the time interval between bone-seeking radiotracers injection and acquisition, it has been reported that images obtained early after [99mTc]Tc-HMDP administration are sufficient to diagnose cardiac amyloidosis. We evaluated the diagnostic performance of [99mTc]Tc-DPD early phase whole body scan with respect to late phase imaging. We qualitatively and semiquantitatively reviewed [99mTc]Tc-DPD imaging of 53 patients referred for suspect cardiac amyloidosis. Findings of early and late phase images were compared with SPECT results (considered the standard-of-reference) determining sensitivity and specificity for visual analysis of each phase imaging and for each semiquantitative index. SPECT imaging was negative for cardiac accumulation in 25 patients and positive in 28. Visual analysis of early phase whole body scan had an extremely significant capability to predict SPECT results; nevertheless, complete agreement was not reached. Visual analysis of late phase imaging showed slightly better results. Semiquantitative analysis of early phase images, namely heart to mediastinum ratio, performed better than semiquantitative analysis of late phase images. Visual analysis of [99mTc]Tc-DPD early phase whole body scan is promising in diagnosing cardiac amyloidosis; further studies are needed to confirm our results in different clinical scenarios. • Visual analysis of early phase planar imaging using [99mTc]Tc-DPD is accurate to diagnose cardiac amyloidosis and may be satisfactory at least in frail patients with high cardiac burden of amyloid fibrils.

The Tangential Velocity Estimation Algorithm for Space-borne SAR

This article presents a discussion of one of the important areas of application of synthetic aperture radars (SAR) – the moving target indication (MTI) mode. The principle of trajectory signal processing in MTI systems is based on the estimation of the Doppler frequency or phase shift of the echo signals due to the movement of objects. The paper describes an algorithm for estimating the tangential velocity of moving targets for the MTI system based on the use two apertures displaced along trajectory of SAR spacecraft. The structure of the MTI system based on the analysis of phase and amplitude radar images is considered. Further, the amplitude and phase characteristics of the moving target are obtained. The block diagram of the tangential velocity estimation algorithm is given. Simulation has been performed and the features of the operation of this algorithm are presented. The errors in estimating of the target tangential velocity are determined.

Prognostic Value of Phase Analysis for Predicting Adverse Cardiac Events Beyond Conventional Single-Photon Emission Computed Tomography Variables: Results From the REFINE SPECT Registry.

Phase analysis of single-photon emission computed tomography myocardial perfusion imaging provides dyssynchrony information which correlates well with assessments by echocardiography, but the independent prognostic significance is not well defined. This study assessed the independent prognostic value of single-photon emission computed tomography-myocardial perfusion imaging phase analysis in the largest multinational registry to date across all modalities. From the REFINE SPECT (Registry of Fast Myocardial Perfusion Imaging With Next Generation SPECT), a total of 19 210 patients were included (mean age 63.8±12.0 years and 56% males). Poststress total perfusion deficit, left ventricular ejection fraction, and phase variables (phase entropy, bandwidth, and SD) were obtained automatically. Cox proportional hazards analyses were performed to assess associations with major adverse cardiac events (MACE). During a follow-up of 4.5±1.7 years, 2673 (13.9%) patients experienced MACE. Annualized MACE rates increased with phase variables and were ≈4-fold higher between the second and highest decile group for entropy (1.7% versus 6.7%). Optimal phase variable cutoff values stratified MACE risk in patients with normal and abnormal total perfusion deficit and left ventricular ejection fraction. Only entropy was independently associated with MACE. The addition of phase entropy significantly improved the discriminatory power for MACE prediction when added to the model with total perfusion deficit and left ventricular ejection fraction (P<0.0001). In a largest to date imaging study, widely representative, international cohort, phase variables were independently associated with MACE and improved risk stratification for MACE beyond the prediction by perfusion and left ventricular ejection fraction assessment alone. Phase analysis can be obtained fully automatically, without additional radiation exposure or cost to improve MACE risk prediction and, therefore, should be routinely reported for single-photon emission computed tomography-myocardial perfusion imaging studies.

Nanoscale Material Heterogeneity of Glowworm Capture Threads Revealed by AFM.

Adhesive materials used by many arthropods for biological functions incorporate sticky substances and a supporting material that operate synergistically by exploiting substrate attachment and energy dissipation. While there has been much focus on the composition and properties of the sticky glues of these bio-composites, less attention has been given to the materials that support them. In particular, as these materials are primarily responsible for dissipation during adhesive pull-off, little is known of the structures that give rise to functionality, especially at the nano-scale. In this study we used tapping mode atomic force microscopy (TM-AFM) to analyze unstretched and stretched glowworm (Arachnocampa tasmaniensis) capture threads and revealed nano-scale features corresponding to variation in surface structure and elastic modulus near the surface of the silk. Phase images demonstrated a high resolution of viscoelastic variation and revealed mostly globular and elongated features in the material. Increased vertical orientation of 11–15 nm wide fibrillar features was observed in stretched threads. Fast Fourier transform analysis of phase images confirmed these results. Relative viscoelastic properties were also highly variable at inter- and intra-individual levels. Results of this study demonstrate the practical usefulness of TM-AFM, especially phase angle imaging, in investigating the nano-scale structures that give rise to macro-scale function of soft and highly heterogeneous materials of both natural and synthetic origins.

Application of digital holographic microscopy to evaluate the dynamics of a single red blood cell influenced by low-power laser light

In the paper, a shift of individual human erythrocytes drifts speed, stimulated by various low-power lasers irradiation, was studied by digital holographic microscopy (DHM). Well known in physiotherapy, a low-level-laser-therapy (LLLT) scanner was used as the stimulation light source, with diode and He-Ne lasers to compare.In the article, an open-source image processing algorithm for simultaneous dynamics and geometrical properties evaluations of the red blood cells is proposed. A strong influence of the low-level red light on the red blood cells dynamics was observed. The effect is important for a better understanding of the laser treatment mechanism.The proposed phase image analysis algorithm significantly improves the individual cells tracing precision for a life science application. The programme might be useful for optical tweezer, imaging flow cytometry, or high precision cells-photon interaction research.

A radiomics-based model to classify the etiology of liver cirrhosis using gadoxetic acid-enhanced MRI

The implementation of radiomics in radiology is gaining interest due to its wide range of applications. To develop a radiomics-based model for classifying the etiology of liver cirrhosis using gadoxetic acid-enhanced MRI, 248 patients with a known etiology of liver cirrhosis who underwent 306 gadoxetic acid-enhanced MRI examinations were included in the analysis. MRI examinations were classified into 6 groups according to the etiology of liver cirrhosis: alcoholic cirrhosis, viral hepatitis, cholestatic liver disease, nonalcoholic steatohepatitis (NASH), autoimmune hepatitis, and other. MRI examinations were randomized into training and testing subsets. Radiomics features were extracted from regions of interest segmented in the hepatobiliary phase images. The fivefold cross-validated models (2-dimensional—(2D) and 3-dimensional—(3D) based) differentiating cholestatic cirrhosis from noncholestatic etiologies had the best accuracy (87.5%, 85.6%), sensitivity (97.6%, 95.6%), predictive value (0.883, 0.877), and area under curve (AUC) (0.960, 0.910). The AUC was larger in the 2D-model for viral hepatitis, cholestatic cirrhosis, and NASH-associated cirrhosis (P-value of 0.05, 0.05, 0.87, respectively). In alcoholic cirrhosis, the AUC for the 3D model was larger (P = 0.01). The overall intra-class correlation coefficient (ICC) estimates and their 95% confident intervals (CI) for all features combined was 0.68 (CI 0.56–0.87) for 2D and 0.71 (CI 0.61–0.93) for 3D measurements suggesting moderate reliability. Radiomics-based analysis of hepatobiliary phase images of gadoxetic acid-enhanced MRI may be a promising noninvasive method for identifying the etiology of liver cirrhosis with better performance of the 2D- compared with the 3D-generated models.

Gated single-photon emission computed tomography myocardial perfusion imaging phase analysis as an imaging biomarker for mortality prediction in heart failure patients undergoing cardiac resynchronization therapy.

Cardiac resynchronization therapy (CRT) reduces morbidity and mortality in heart failure patients. The purpose of this study was to assess the value of gated myocardial perfusion single-photon emission computed tomography (GMPS) phase analysis for predicting survival in heart failure patients undergoing CRT. This retrospective cohort study evaluated heart failure patients who underwent GMPS prior to CRT. Phase histogram bandwidth (PHB) and phase SD (PSD) were calculated using GMPS data. Cox proportional hazards model was used to identify independent predictors of overall survival (OS). A total of 35 patients (age 65.1 ± 13.3, 27 men and 8 women), who were followed for mean of 4.1 ± 2.9 years, were enrolled in the study. PSD of greater than 45° was found to be an independent predictor of poor OS (hazard ratio = 12.63, P = 0.011) when compared with age (hazard ratio = 1.00, P = 0.922), gender (hazard ratio = 0.31, P = 0.155), NYHA class (hazard ratio = 0.45, P = 0.087), QRS duration greater than 150 ms (hazard ratio = 2.38, P = 0.401), pre-CRT left ventricular ejection fraction (LVEF) (hazard ratio = 0.95, P = 0.175) and etiology of heart failure (hazard ratio = 1.42, P = 0.641). Furthermore, PHB greater than 140° was also found to be an independent predictor of poor OS (hazard ratio = 5.63, P = 0.040) when compared with age, gender, NYHA class, QRS duration greater than 150 ms, pre-CRT LVEF and etiology of heart failure. PSD and PHB, measured by GMPS, may serve as biomarkers for the prediction of survival in patients undergoing CRT.

Regulation of Cyclic Nucleotide Phosphodiesterase 1 by Endoplasmic Reticulum Stress Contributes to Homocysteine‐induced Cardiac Hypertrophy

Objectives Mechanistic understanding of the role of homocysteine in the development of cardiac hypertrophy is inadequate at present. This study aimed to elucidate the association of cyclic nucleotide phosphodiesterase 1 (PDE1) and endoplasmic reticulum (ER) stress with cardiomyocyte hypertrophy induced by homocysteine. Methods H9c2 cardiomyocytes were allocated to control group and homocysteine-treated group in the presence or absence of ER stress inhibitor tauroursodeoxycholic acid (TUDCA) or PDE1 inhibitor Lu AF58027 for 72h. In another set of experiment, H9c2 cells were transfected with specific siRNA targeting PDE1 subtypes prior to homocysteine exposure. The cell surface area was measured by phase contrast microscope and image analysis software and ultrastructural changes of the cells were observed under transmission electron microscopy. Quantitative polymerase chain reaction and western blot were employed to detect the mRNA and protein expression of the hypertrophic markers beta-smooth muscle myosin heavy chain (β-MHC) and atrial natriuretic peptide (ANP), PDE1 subtypes (PDE1A, 1B, and 1C), and ER stress molecules (GRP78, phosphor-PERK, PERK, phosphor-IRE1, IRE1, and ATF6). The intracellular levels of cyclic guanosine monophosphate (cGMP) and cyclic adenosine monophosphate (cAMP) were measured by enzyme linked immunosorbent assay. Results Homocysteine exposure resulted in an enlargement in cell size and an increase in β-MHC and ANP expression. Homocysteine induced ER stress in H9c2 cells, shown by increased expression of GRP78 and enhanced phosphorylation of PERK and IRE1, as well as dilatation and degranulation of rough ER. The expression of PDE1A and PDE1C was significantly upregulated by homocysteine. Inhibition of ER stress or PDE1 suppressed homocysteine-induced upregulation of β-MHC and ANP and alleviated cell enlargement. In addition, the protein expression of PDE1A and PDE1C in homocysteine-exposed H9c2 cells was downregulated by the ER stress inhibitor TUDCA. Silencing of PDE1C significantly inhibited homocysteine-induced cell hypertrophy whereas knockdown of PDE1A showed minor effect. Both cAMP and cGMP levels were lowered in H9c2 cells subjected to homocysteine exposure, while only cAMP content could be restored by Lu AF58027 and TUDCA. Conclusions ER stress mediates homocysteine-induced cardiomyocyte hypertrophy via upregulating PDE1 expression. Cyclic nucleotide, in particular cAMP, is the downstream mediator of the ER stress-PDE1 signaling axis in homocysteine-induced hypertrophy.

Association Between Soluble Epoxide Hydrolase and TRPC3 Channels in Pathological Cardiac Hypertrophy

Objectives Hyperhomocysteinemia is an independent risk factor for cardiovascular disease. Although previous studies have shown a positive correlation between homocysteine levels and the incidence of cardiac hypertrophy and remodeling, the molecular mechanisms by which homocysteine promotes the development of cardiac hypertrophy remain inadequately understood. In this study, we investigated the role of soluble epoxide hydrolase (sEH) and transient receptor potential isoform 3 (TRPC3) channels in homocysteine-induced cardiac hypertrophy with further elucidating the association between sEH and TRPC3. Methods H9c2 cardiomyocytes were exposed to different concentrations of homocysteine ranging from 25 to 200 μmol/L for different duration. The cell surface area was measured by phase contrast microscope and image analysis software. The mRNA and protein expressions of sEH, TRPC3 channels, and hypertrophic markers beta-smooth muscle myosin heavy chain (β-MHC) and atrial natriuretic peptide (ANP) were detected by quantitative polymerase chain reaction and western blot. Results Homocysteine treatment dose-dependently and time-dependently increased the expression of β-MHC and ANP in H9c2 cardiomyocytes. Both mRNA and protein levels of sEH and TRPC3 channels were unregulated by homocysteine. Inhibition of sEH with 1-trifluoromethoxyphenyl-3-(1-propionylpiperidin-4-yl) urea (TPPU) significantly suppressed homocysteine-induced upregulation of β-MHC and ANP and attenuated the increase of cell size. Pyr3, a selective TRPC3 channel blocker, also exerted a strong anti-hypertrophic effect against homocysteine. Treatment with TPPU significantly suppressed the expression of TRPC3 channels in homocysteine-exposed H9c2 cells. Conclusions: Both sEH and TRPC3 channels are involved in homocysteine-induced hypertrophy of cardiomyocytes. TRPC3 channels may act as a downstream mediator for sEH activation induced by homocysteine to promote cardiac hypertrophy.

Підтримка прийняття рішень в системі поляризаційної зображальної діагностики гістологічних зрізів за аналізом їх параметрів анізотропії

The method and subsystem of decision support according to the principles of fuzzy logic for the system of polarization imaging diagnostics of histological sections are developed. Informative signs of diagnostics on the basis of statistical and correlation analysis of orientation and phase images of sections of biological tissues are determined. Mathematical models of the membership functions of the states norm and pathology of the studied histological sections for the decisive rule in the system are proposed.

Analysis of the relief of MCF-7 tumor cells during apoptisis on the basis of phase-contrast images obtained by laser interference microscopy

Data on the surface topography of the cell makes it possible to predict its behavior and is an indicator to assess whether it is in a state of apoptosis, that is, in a state of death due to the activation of intracellular reactions; this state of a cell occurs both during normal development and as a result of a pathological process. A universal method for recording the state of the relief of the cell and its other mechanobiological parameters has not been developed, and therefore laser interference microscopy is promising for this purpose. The aim of this work is to evaluate the state of the surface of tumor cells during the apoptotic changes in breast cancer cells by analyzing the phase contrast (phase) images obtained by laser interference microscopy. The object of the study is the cells of the MCF-7 line (epithelial-like adenocarcinoma of the human mammary gland) in a native state and in a state of induced apoptosis under the action of doxorubicin. The analysis of the cell surface involves interpretation of data on the optical thickness of cells and their morphology through the construction of isolines. Based on the analysis of phase images of cells, their general morphometric parameters were determined. Visualization of optical data and their interpretation was performed using the ImageJ-Fiji software. According to the Wilcoxnon-Mann-Whitney test, the samples under study are significantly different in maximum diameter, perimeter, and sphericity coefficient. Based on the analysis of isolinear images, a diagram of the phase state of cells in a native state and in a state of apoptosis was constructed. According to the diagram, the cross-sectional area of apoptotic cells is generally much smaller than the cross-sectional area of native cells at the same height levels. The characteristics of cells within the framework of the proposed phase diagram are consistent with the morphological cell apoptosis signs, which are recorded using classical microscopic methods. The construction of the diagrams of the state of cells according to the parameters of their relief holds promise for assessing the cellular behavior, predicting it, as well as for analyzing the effect of drugs and therapeutic methods on pathological cells.

Nucleation and growth of gas bubbles in AlSi8Mg4 foam investigated by X-ray tomoscopy

Initiation and growth of metal foam is a complex and dynamical process, which is intrinsically three-dimensional and time-dependent. Tomoscopy –or time-resolved tomography– allows us to follow the nucleation and growth of gas bubbles in AlSi8Mg4 alloy in real time during foaming. The location, size and shape of individual bubbles was determined in steps of 1 s with spatial resolutions of a few µm. Moreover, the constituents responsible for gas evolution, namely Al-Mg phases and TiH2 particles, were identified in the series of 3D images. Automated quantitative image analysis of bubbles and gas-generated phases including their spatial correlations allowed us to break down the foaming process into two distinct steps, a first homogenous one driven by adsorbed gases and first melting microstructural components and a second attributed to the melting of the alloy and subsequent foam growth driven by hydrogen released from TiH2 particles. The results of the study indicate that standard AlSi8Mg4 foam can be improved by tailoring the properties of the Al-Mg constituent powder.