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Abstract Type 2 diabetes mellitus (T2DM) is a major public health concern with significant cardiovascular complications (CVD). Despite extensive epidemiological data, the molecular mechanisms relating hyperglycemia to CVD remain incompletely understood. We here investigated the impact of chronic hyperglycemia on human aortic smooth muscle cells (HASMCs) cultured under varying glucose conditions in vitro, mimicking normal (5 mmol/L), pre-diabetic (10 mmol/L), and diabetic (20 mmol/L) conditions, respectively. Normal HASMC cultures served as baseline controls, and patient-derived T2DM-SMCs served as disease controls. Results showed significant increases in cellular proliferation, area, perimeter, and F-actin expression with increasing glucose concentration (p

Background Pyroptosis executor GsdmD (gasdermin D) promotes atherosclerosis in mice and humans. Disulfiram was recently shown to potently inhibit GsdmD, but the in vivo efficacy and mechanism of disulfiram's antiatherosclerotic activity is yet to be explored. Methods and Results We used human/mouse macrophages, endothelial cells, and smooth muscle cells and a hyperlipidemic mouse model of atherosclerosis to determine disulfiram antiatherosclerotic efficacy and mechanism. The effects of disulfiram on several atheroprotective pathways such as autophagy, efferocytosis, phagocytosis, and gut microbiota were determined. Atomic force microscopy was used to determine the effects of disulfiram on the biophysical properties of the plasma membrane of macrophages. Disulfiram‐fed hyperlipidemic apolipoprotein E−/− mice showed significantly reduced interleukin‐1β release upon in vivo Nlrp3 (NLR family pyrin domain containing 3) inflammasome activation. Disulfiram‐fed mice showed smaller atherosclerotic lesions (~27% and 29% reduction in males and females, respectively) and necrotic core areas (~50% and 46% reduction in males and females, respectively). Disulfiram induced autophagy in macrophages, smooth muscle cells, endothelial cells, hepatocytes/liver, and atherosclerotic plaques. Disulfiram modulated other atheroprotective pathways (eg, efferocytosis, phagocytosis) and gut microbiota. Disulfiram‐treated macrophages showed enhanced phagocytosis/efferocytosis, with the mechanism being a marked increase in cell‐surface expression of efferocytic receptor MerTK. Atomic force microscopy analysis revealed altered biophysical properties of disulfiram‐treated macrophages, showing increased order‐state of plasma membrane and increased adhesion strength. Furthermore, 16sRNA sequencing of disulfiram‐fed hyperlipidemic mice showed highly significant enrichment in atheroprotective gut microbiota Akkermansia and a reduction in atherogenic Romboutsia species. Conclusions Taken together, our data show that disulfiram can simultaneously modulate several atheroprotective pathways in a GsdmD‐dependent as well as GsdmD‐independent manner.

Various forms of pesticides have been reported to be among the environmental toxicants, which are detrimental to human health. The active ingredients of these formulations can enter the human body through air, food, or water. Epidemiological studies suggest that these compounds strongly affect the developing brain in fetal and infant stages due to their ability to breach the underdeveloped blood–brain barrier. Since neural progenitor stem cells (NPCs) in the developing brain are the most vulnerable to these compounds, the mechanisms by which NPCs experience toxicity upon exposure to these chemicals must be investigated. Here, we assessed the viability of human fetal NPCs in 2D cultures in the presence of the active ingredients of six widely used pesticides using Live/Dead® and Hoechst staining. The IC50 values ranged from 4.1–201 μM. A significant drop in cell viability with increasing toxicant concentration (p < 0.01) was noted, with the order of toxicity being malathion < 4-aminopyridine < methoprene < prallethrin < temephos < pyriproxyfen. Changes in cellular biomechanical characteristics (Young’s modulus, tether force, membrane tension, and tether radius) were quantified using atomic force microscopy, whereas cell migration was elucidated over 48 h using a customized wound-healing assay. The Young’s modulus of fetal NPCs exposed to IC50/2 doses of these compounds was reduced by 38–70% and that of those exposed to IC50 doses was reduced by 71–80% (p < 0.001 vs. controls for both; p < 0.01 for IC50 vs. IC50/2 for each compound). Similar patterns were noted for tether forces and membrane tension in fetal NPCs. NPC migration was found to be compound type- and dose-dependent. These results attest to the significant detrimental effects of these compounds on various aspects of the human fetal NPC phenotype, and the utility of cell mechanics as a marker to assess developmental neurotoxicity.

Abstract Endometriosis is a pathological condition of the female reproductive tract characterized by the existence of endometrium-like tissue at ectopic sites, affecting 10% of women between the age 15 and 49 in the USA. However, currently there is no reliable non-invasive method to detect the presence of endometriosis without surgery and many women find hormonal therapy and surgery as ineffective in avoiding the recurrences. There is a lack of knowledge on the etiology and the factors that contribute to the development of endometriosis. A growing body of recent evidence suggests an association between gut microbiota and endometriosis pathophysiology. However, the direct impact of microbiota and microbiota-derived metabolites on the endometriosis disease progression is largely unknown. To understand the causal role of gut microbiota and endometriosis, we have implemented a novel model using antibiotic-induced microbiota-depleted (MD) mice to investigate the endometriosis disease progression. Interestingly, we found that MD mice showed reduced endometriotic lesion growth and, the transplantation of gut microbiota by oral gavage of feces from mice with endometriosis rescued the endometriotic lesion growth. Additionally, using germ-free donor mice, we indicated that the uterine microbiota is dispensable for endometriotic lesion growth in mice. Furthermore, we showed that gut microbiota modulates immune cell populations in the peritoneum of lesions-bearing mice. Finally, we found a novel signature of microbiota-derived metabolites that were significantly altered in feces of mice with endometriosis. Finally, we found one the altered metabolite, quinic acid promoted the survival of endometriotic epithelial cells in vitro and lesion growth in vivo, suggesting the disease-promoting potential of microbiota-derived metabolites. In summary, these data suggest that gut microbiota and microbiota-derived metabolome contribute to lesion growth in mice, possibly through immune cell adaptations. Of translational significance, these findings will aid in designing non-invasive diagnostics using stool metabolites for endometriosis.

Miniaturization of liquid chromatography could help enhance sensitivity, reduce solvent usage, and detect small quantities of peptides. However, it demands better sample homogenization of the mobile phase. We here developed a mixer design based on the inline Kenics geometry, consisting of a periodic arrangement of twisted blades placed inside a cylindrical capillary that repeatedly cut and stack fluid elements to achieve rapid mixing in laminar flow regimes. The mixer design was optimized with respect to the twist angle and aspect ratio of the mixing units to achieve complete mixing at minimum pressure load cost. Results suggest that for optimal designs, for a mixer volume of ~70 μL, complete mixing is achieved within a distance smaller than 4 cm for a broad set of flow rate conditions ranging from 75 μL·min−1 to 7.5 mL·min−1. A salient feature that we introduce and test for the first time is the physical flexibility of the cylindrical capillary. The performance of the design remained robust when the mixing section was not rigid and bent in different topologies, as well as when changing the chemical composition of the mobile phase used.

During development and pathologies of the central nervous system, blood vessels are closely connected with the innate immune cells, microglia. Here, the authors report that microglia adjust their angiogenic program to shape blood vessels and may depend on tissue stiffness.

Computational fluid dynamics modeling was used to characterize the effect of the integration of constrictions defined by the vertices of hyperbolas on the flow structure in microfluidic serpentine channels. In the new topology, the Dean flows characteristic of the pressure-driven fluid motion along curved channels are combined with elongational flows and asymmetric longitudinal eddies that develop in the constriction region. The resulting complex flow structure is characterized by folding and stretching of the fluid volumes, which can promote enhanced mixing. Optimization of the geometrical parameters defining the constriction region allows for the development of an efficient micromixer topology that shows robust enhanced performance across a broad range of Reynolds numbers from Re = 1 to 100.

Computational fluid dynamics modeling at Reynolds numbers ranging from 10 to 100 was used to characterize the performance of a new type of micromixer employing a serpentine channel with a grooved surface. The new topology exploits the overlap between the typical Dean flows present in curved channels due to the centrifugal forces experienced by the fluids, and the helical flows induced by slanted groove-ridge patterns with respect to the direction of the flow. The resulting flows are complex, with multiple vortices and saddle points, leading to enhanced mixing across the section of the channel. The optimization of the mixers with respect to the inner radius of curvature (Rin) of the serpentine channel identifies the designs in which the mixing index quality is both high (M > 0.95) and independent of the Reynolds number across all the values investigated.

Miniaturization of liquid chromatography could help enhance sensitivity, reduce solvent usage, and detect small quantities of peptides. However, it demands better sample homogenization of the mobile phase. We here developed a mixer design based on the inline Kenics geometry, consisting of a periodic arrangement of twisted blades placed inside a cylindrical capillary that repeatedly cut and stack fluid elements to achieve rapid mixing in laminar flow regimes. The mixer design was optimized with respect to the twist angle and aspect ratio of the mixing units to achieve complete mixing at minimum pressure load cost. Results suggest that for optimal designs, for a mixer volume of ~70 μL, complete mixing is achieved within a distance smaller than 4 cm for a broad set of flow rate conditions ranging from 75 μL·min−1 to 7.5 mL·min−1. A salient feature that we introduce and test for the first time is the physical flexibility of the cylindrical capillary. The performance of the design remained robust when the mixing section was not rigid and bent in different topologies, as well as when changing the chemical composition of the mobile phase used. [ABSTRACT FROM AUTHOR]

Various forms of pesticides have been reported to be among the environmental toxicants, which are detrimental to human health. The active ingredients of these formulations can enter the human body through air, food, or water. Epidemiological studies suggest that these compounds strongly affect the developing brain in fetal and infant stages due to their ability to breach the underdeveloped blood–brain barrier. Since neural progenitor stem cells (NPCs) in the developing brain are the most vulnerable to these compounds, the mechanisms by which NPCs experience toxicity upon exposure to these chemicals must be investigated. Here, we assessed the viability of human fetal NPCs in 2D cultures in the presence of the active ingredients of six widely used pesticides using Live/Dead® and Hoechst staining. The IC50 values ranged from 4.1–201 μM. A significant drop in cell viability with increasing toxicant concentration (p < 0.01) was noted, with the order of toxicity being malathion < 4-aminopyridine < methoprene < prallethrin < temephos < pyriproxyfen. Changes in cellular biomechanical characteristics (Young's modulus, tether force, membrane tension, and tether radius) were quantified using atomic force microscopy, whereas cell migration was elucidated over 48 h using a customized wound-healing assay. The Young's modulus of fetal NPCs exposed to IC50/2 doses of these compounds was reduced by 38–70% and that of those exposed to IC50 doses was reduced by 71–80% (p < 0.001 vs. controls for both; p < 0.01 for IC50 vs. IC50/2 for each compound). Similar patterns were noted for tether forces and membrane tension in fetal NPCs. NPC migration was found to be compound type- and dose-dependent. These results attest to the significant detrimental effects of these compounds on various aspects of the human fetal NPC phenotype, and the utility of cell mechanics as a marker to assess developmental neurotoxicity. [ABSTRACT FROM AUTHOR]

In naval applications generally, the pleated discrete pore non-woven layer filter element is used. Filters used for such applications require a maximized filtration rate, lower pressure drop, higher permeability, effective pore size distribution and good filtration efficiency. In the other most common wire mesh filter element type, the geometric parameters are well-defined and can easily be modelled. In the case of non-woven layer filter element, the pores are arranged in a randomly distributed manner and the modelling becomes difficult. In this present study, a new approach was contemplated for modelling the same. The fluid flow through the filter element is by percolation phenomenon. Using Darcy’s law approach, the pressure drop across the filter element for different flow rates was found analytically by considering the flow resistance in all three polar coordinates r, θ and Z. The theoretical prediction made by CFD analysis is correlated with actual model behaviour and a good degree of correlation is obtained which shows the efficacy of this method for wider use in similar applications. [ABSTRACT FROM AUTHOR]

During nervous system development, numerous cues within the extracellular matrix microenvironment (ECM) guide the growing neurites along specific pathways to reach their intended targets. Neurite motility is controlled by extracellular signal sensing through the growth cone at the neurite tip, including chemoattractive and repulsive cues. However, it is difficult to regenerate and restore neurite tracts, lost or degraded due to an injury or disease, in the adult central nervous system. Thus, it is important to evaluate the dynamic interplay between ECM and the concentration gradients of these cues, which would elicit robust neuritogenesis. Such information is critical in understanding the processes involved in developmental biology, and in developing high-fidelity neurite regenerative strategies post-injury, and in drug discovery and targeted therapeutics for neurodegenerative conditions. Here, we quantitatively investigated this relationship using a combination of mathematical modeling and in vitro experiments, and determined the synergistic role of guidance cues and ECM on neurite outgrowth and turning. Using a biomimetic microfluidic system, we have shown that cortical neurite outgrowth and turning under chemogradients (IGF-1 or BDNF) within 3D scaffolds is highly regulated by the source concentration of the guidance cue and the physical characteristics of the scaffold. A mechanistic-driven partial differential equation model of neurite outgrowth has been proposed, which could also be used prospectively as a predictive tool. The parameters for the chemotaxis term in the model are determined from the experimental data using our microfluidic assay. Resulting model simulations demonstrate how neurite outgrowth was critically influenced by the experimental variables, which was further supported by experimental data on cell-surface-receptor expressions. The model results are in excellent agreement with the experimental findings. This integrated approach represents a framework for further elucidation of biological mechanisms underlying neuronal responses of specialized cell types, during various stages of development, and under healthy or diseased conditions.

Volumetric muscle loss (VML), which involves the loss of a substantial portion of muscle tissue, is one of the most serious acute skeletal muscle injuries in the military and civilian communities. The injured area in VML may be so severely affected that the body loses its innate capacity to regenerate new functional muscles. State-of-the-art biofabrication methods such as bioprinting provide the ability to develop cell-laden scaffolds that could significantly expedite tissue regeneration. Bioprinted cell-laden scaffolds can mimic the extracellular matrix and provide a bioactive environment wherein cells can spread, proliferate, and differentiate, leading to new skeletal muscle tissue regeneration at the defect site. In this study, we engineered alginate–gelatin composite inks that could be used as bioinks. Then, we used the inks in an extrusion printing method to develop design-specific scaffolds for potential VML treatment. Alginate concentration was varied between 4–12% w/v, while the gelatin concentration was maintained at 6% w/v. Rheological analysis indicated that the alginate–gelatin inks containing 12% w/v alginate and 6% w/v gelatin were most suitable for developing high-resolution scaffolds with good structural fidelity. The printing pressure and speed appeared to influence the printing accuracy of the resulting scaffolds significantly. All the hydrogel inks exhibited shear thinning properties and acceptable viscosities, though 8–12% w/v alginate inks displayed properties ideal for printing and cell proliferation. Alginate content, crosslinking concentration, and duration played significant roles (p < 0.05) in influencing the scaffolds' stiffness. Alginate scaffolds (12% w/v) crosslinked with 300, 400, or 500 mM calcium chloride (CaCl2) for 15 min yielded stiffness values in the range of 45–50 kPa, i.e., similar to skeletal muscle. The ionic strength of the crosslinking concentration and the alginate content significantly (p < 0.05) affected the swelling and degradation behavior of the scaffolds. Higher crosslinking concentration and alginate loading enhanced the swelling capacity and decreased the degradation kinetics of the printed scaffolds. Optimal CaCl2 crosslinking concentration (500 mM) and alginate content (12% w/v) led to high swelling (70%) and low degradation rates (28%) of the scaffolds. Overall, the results indicate that 12% w/v alginate and 6% w/v gelatin hydrogel inks are suitable as bioinks, and the printed scaffolds hold good potential for treating skeletal muscle defects such as VML. [ABSTRACT FROM AUTHOR]

Computational fluid dynamics modeling was used to characterize the effect of the integration of constrictions defined by the vertices of hyperbolas on the flow structure in microfluidic serpentine channels. In the new topology, the Dean flows characteristic of the pressure-driven fluid motion along curved channels are combined with elongational flows and asymmetric longitudinal eddies that develop in the constriction region. The resulting complex flow structure is characterized by folding and stretching of the fluid volumes, which can promote enhanced mixing. Optimization of the geometrical parameters defining the constriction region allows for the development of an efficient micromixer topology that shows robust enhanced performance across a broad range of Reynolds numbers from Re = 1 to 100. [ABSTRACT FROM AUTHOR]

Byline: Subhash. Kaul, Suvarna. Alladi, K. Mridula, V C S. Bandaru, Matapathi. Umamashesh, Darapureddy. Anjanikumar, Palli. Lalitha, R. Chandrasekhar Background: Asymptomatic carotid artery stenosis (ACAS) is a marker for cerebrovascular [...]

Piezoelectric properties of epitaxial ZnO thin films grown on R-plane sapphire substrates using metal organic chemical vapor deposition (MOCVD) are examined. High quality epitaxial films with films with atomically sharp film-substrate interfaces were obtained.