Aim
To microscopically examine the cleanliness of root canal walls that remained unprepared as revealed by micro‐CT.
Methodology
The root canals of 10 freshly extracted mandibular premolars with ...necrotic pulps and apical periodontitis along with the mesiobuccal canals of 11 mandibular molars with vital pulps were prepared using Reciproc instruments R40 and R25, respectively, and 2.5% sodium hypochlorite irrigation. Specimens were scanned in micro‐CT before and after preparation, and the unprepared areas were identified. The outer root surface corresponding to the untouched areas was marked on each root third to guide further analysis using histological (for teeth with vital pulps) and scanning electron microscopic (SEM; for necrotic teeth) examination. In the teeth with vital pulps, the root canal area occupied by tissue remnants was calculated. In SEM analysis of teeth with necrotic pulps, scores were attributed for the amount of debris on the untouched areas.
Results
The proportion of unprepared areas in the mesiobuccal molar canals was 18.1% and 9.6% over the full canal length and apical canal, respectively. In premolars, corresponding figures were 34.6% and 17.6%, respectively. Histological analysis of canals with vital pulps revealed tissue remnants over the untouched walls almost exclusively in the apical canal. SEM analysis of the canals with necrotic pulps revealed debris along the untouched walls in all root canal thirds.
Conclusion
The areas that remain untouched by Reciproc instruments used with 2.5% NaOCl irrigation as revealed by micro‐CT analysis were usually covered with debris, in the form of pulp tissue remnants, bacteria and dentine chips, especially in the apical root canal.
Whistler-mode chorus waves propagate outside the plasmasphere, interacting with energetic electrons in the outer radiation belt. This leads to local changes in the phase space density distribution ...due to energy or pitch angle diffusion. The wave–particle interaction time (Tr) is crucial in estimating time-dependent processes such as the energy and pitch angle diffusion. Although the wave group and particle velocities are a fraction of the speed of light, the kinematics description of the wave–particle interaction for relativistic electrons usually considers the relativistic Doppler shift in the resonance condition and relativistic motion equation. This relativistic kinematics description is incomplete. In this paper, to the literature we add a complete relativistic description of the problem that relies on the relativistic velocity addition (between the electron and the wave) and the implications of the different reference frames for the estimates of the interaction time. We use quasi-linear test particle equations and the special relativity theory applied to whistler-mode chorus waves parallel propagating in cold-plasma magnetosphere interaction with relativistic electrons. Also, we consider that the resonance occurs in the electron's reference frame. At the same time, the result of such interaction and their parameters are measured in the local inertial reference frame of the satellite. The change pitch angle and the average diffusion coefficient rates are then calculated from the relativistic interaction time. The interaction time equation is consistent with previous works in the limit of non-relativistic interactions (Tnr). For the sake of application, we provide the interaction time and average diffusion coefficient Daa for four case studies observed during the Van Allen Probes era. Our results show that the interaction time is generally longer when applying the complete relativistic approach, considering a non-relativistic calculation. From the four case studies, the ratio Tr/Tnr varies in the range 1.7–3.0 and Daa/Daanr in the range 1.9–5.4. Accurately calculating the interaction time with full consideration of special relativity can enhance the modeling of the electron flux in Earth's outer radiation belt. Additionally, the change in pitch angle depends on the time of interaction, and similar discrepancies can be found when the time is calculated with no special relativity consideration. The results described here have several implications for modeling relativistic outer-radiation-belt electron flux resulting from the wave–particle interaction. Finally, since we considered only one wave cycle interaction, the average result from some interactions can bring more reliable results in the final flux modeling.
Hepatocellular carcinoma (HCC) is the most frequently detected primary malignant liver tumor, representing a worldwide public health problem due to its high morbidity and mortality rates. The HCC is ...commonly detected in advanced stage, precluding the use of treatments with curative intent. For this reason, it is crucial to find effective therapies for HCC. Cancer cells have a high dependence of glycolysis for ATP production, especially under hypoxic environment. Such dependence provides a reliable possible strategy to specifically target cancer cells based on the inhibition of glycolysis. HCC, such as other cancer types, presents a clinically well-known upregulation of several glycolytic key enzymes and proteins, including glucose transporters particularly glucose transporter 1 (GLUT1). Such enzymes and proteins constitute potential targets for therapy. Indeed, for some of these targets, several inhibitors were already reported, such as 2-Deoxyglucose, Imatinib or Flavonoids. Although the inhibition of glycolysis presents a great potential for an anticancer therapy, the development of glycolytic inhibitors as a new class of anticancer agents needs to be more explored. Herein, we propose to summarize, discuss and present an overview on the different approaches to inhibit the glycolytic metabolism in cancer cells, which may be very effective in the treatment of HCC.
A novel anaerobic, thermophilic, carbon monoxide-utilizing bacterium, strain E3-OT, was isolated from anaerobic sludge from a municipal solid waste digester. Cells were straight rods, 0.6–1 µm in ...diameter and 2–3 µm in length and grew as single cells or in pairs. Cells formed round terminal endospores. The temperature range for growth was 50–70 °C, with an optimum at 65 °C. The pH range for growth was 5.7–8.0, with an optimum at 7.5. Strain E3-OT had the ability to ferment various sugars, such as fructose, galactose, glucose, mannose, raffinose, ribose, sucrose and xylose, producing mainly H2 and acetate. In addition, the isolate was able to grow with CO as the sole carbon and energy source. CO oxidation was coupled to H2 and CO2 formation. The G+C content of the genomic DNA was 54.6 mol%. Based on 16S rRNA gene sequence analysis, this bacterium is most closely related to Moorella glycerini (97 % sequence identity). Based on the physiological features and phylogenetic analysis, it is proposed that strain E3-OT should be classified in the genus Moorella as a representative of a novel species, Moorella stamsii. The type strain of Moorella stamsii is E3-OT ( = DSM 26271T = CGMCC 1.5181T).
Aim and Methods
Although the antimicrobial activity of extracts from several mushroom species has been reported, studies with the individual compounds present in that extracts are scarce. Herein, the ...antimicrobial activity of different phenolic compounds identified and quantified in mushroom species from all over the world was evaluated. Furthermore, a structure–activity relationship (SAR) analysis and molecular docking studies were performed, in order to provide insights into the mechanism of action of potential antimicrobial drugs for resistant micro‐organisms.
Results
2,4‐Dihydroxybenzoic and protocatechuic acids were the phenolic compounds with higher activity against the majority of Gram‐negative and Gram‐positive bacteria. Furthermore, phenolic compounds inhibited more MRSA than methicillin‐susceptible Staphylococcus aureus. MRSA was inhibited by 2,4‐dihydroxybenzoic, vanillic, syringic (MICs = 0·5 mg ml−1) and p‐coumaric (MIC = 1 mg ml−1) acids, while these compounds at the same concentrations had no inhibitory effects against methicillin‐susceptible Staph. aureus.
Conclusions
The presence of carboxylic acid (COOH), two hydroxyl (OH) groups in para and ortho positions of the benzene ring and also a methoxyl (OCH3) group in the meta position seems to be important for anti‐MRSA activity.
Significance and Impact of the Study
Phenolic compounds could be used as antimicrobial agents, namely against some micro‐organisms resistant to commercial antibiotics.
Rigid polyurethane foams were prepared by the one-step expandable foam method using casting molding followed by forming clay-based composites. Polyurethane/vermiculite foam composites (PU/VMT) were ...controlled based on adding the percentage of clay in the formulation. The effects of composite modifications were evaluated by X-ray diffraction (XRD), thermogravimetric analysis (TG/DTG), and scanning electron microscopy (SEM/EDS) applied to the flame retardancy explored by the vertical burn test. The results indicated that adding clay controlled the particle size concerning polyurethane (PU) foams. However, they exhibited spherical structures with closed cells with relatively uniform distribution. XRD analysis showed the peaks defined at 2θ = 18° and 2θ = 73° relative to the crystallinity in formation and interaction of rigid segments were identified, as well as the influence of crystallinity reduction in composites. In the flame test, the flame retardant surface was successful in all composites, given the success of the dispersibility and planar orientation of the clay layers and the existence of an ideal content of vermiculite (VMT) incorporated in the foam matrix.
Class 1 myosins (Myo1s) were the first unconventional myosins identified and humans have eight known Myo1 isoforms. The Myo1 family is involved in the regulation of gene expression, cytoskeletal ...rearrangements, delivery of proteins to the cell surface, cell migration and spreading. Thus, the important role of Myo1s in different biological processes is evident. In this study, we have investigated the effects of pentachloropseudilin (PClP), a reversible and allosteric potent inhibitor of Myo1s, on angiogenesis. We demonstrated that treatment of cells with PClP promoted a decrease in the number of vessels. The observed inhibition of angiogenesis is likely to be related to the inhibition of cell proliferation, migration and adhesion, as well as to alteration of the actin cytoskeleton pattern, as shown on a PClP‐treated HUVEC cell line. Moreover, we also demonstrated that PClP treatment partially prevented the delivery of integrins to the plasma membrane. Finally, we showed that PClP caused DNA strand breaks, which are probably repaired during the cell cycle arrest in the G1 phase. Taken together, our results suggest that Myo1s participate directly in the angiogenesis process.
Inhibition of angiogenesis by the allosteric myosin 1 inhibitor pentachloropseudilin (PClP) is explained by inhibition of cell proliferation, migration and adhesion, as well as by alteration of the actin cytoskeleton pattern. Moreover, PClP treatment partially prevents the delivery of integrins to the plasma membrane and causes DNA strand breaks. Thus, class 1 myosins are directly involved in the angiogenesis process.
Three‐dimensional (3D) cultures of human pluripotent stem cell derived cardiomyocytes (hPSC‐CMs) hold great promise for drug discovery, providing a better approximation to the in vivo physiology over ...standard two‐dimensional (2D) monolayer cultures. However, the transition of CM differentiation protocols from 2D to 3D cultures is not straightforward. In this work, we relied on the aggregation of hPSC‐derived cardiac progenitors and their culture under agitated conditions to generate highly pure cardiomyocyte aggregates. Whole‐transcriptome analysis and 13C‐metabolic flux analysis allowed to demonstrate at both molecular and fluxome levels that such 3D culture environment enhances metabolic maturation of hiPSC‐CMs. When compared to 2D, 3D cultures of hiPSC‐CMs displayed down‐regulation of genes involved in glycolysis and lipid biosynthesis and increased expression of genes involved in OXPHOS. Accordingly, 3D cultures of hiPSC‐CMs had lower fluxes through glycolysis and fatty acid synthesis and increased TCA‐cycle activity. Importantly, we demonstrated that the 3D culture environment reproducibly improved both CM purity and metabolic maturation across different hPSC lines, thereby providing a robust strategy to derive enriched hPSC‐CMs with metabolic features closer to that of adult CMs.
This study describes a simple and efficient method to generate human pluripotent stem cell‐derived cardiomyocytes (hPSC‐CMs) with improved metabolic maturation. The strategy consists in promoting cell aggregation at the cardiac progenitor stage to increase protocol reproducibility. By using an integrated experimental and computational systems biology approach, this work compares 2D monolayers and 3D aggregate cultures and shows that the later improves hPSC‐CM commitment and enrichment, and the energetic metabolism of the generated CMs more closely resembles that of adult CMs.
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