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This study introduces a physics-regularized neural network (PRNN) as a computational approach to predict silicon carbide's (SiC) swelling under irradiation, particularly at high temperatures. The PRNN model combines physics-based regularization with neural network methodologies to generalize the behavior of SiC, even in conditions beyond the traditional empirical model's valid range. This approach ensures continuity and accuracy in SiC behavior predictions in extreme environments. A key aspect of this research is using nested cross-validation to ensure robustness and generalizability. The PRNN model effectively bridges empirical and sparse experimental data by integrating prior knowledge and refined tuning procedures. It demonstrates its SiC's predictive power in high-irradiation conditions essential for nuclear and aerospace applications., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Breathing conditions affect a wide range of people, including those with respiratory issues like asthma and sleep apnea. Smartwatches with photoplethysmogram (PPG) sensors can monitor breathing. However, current methods have limitations due to manual parameter tuning and pre-defined features. To address this challenge, we propose the PPG2RespNet deep-learning framework. It draws inspiration from the UNet and UNet + + models. It uses three publicly available PPG datasets (VORTAL, BIDMC, Capnobase) to autonomously and efficiently extract respiratory signals. The datasets contain PPG data from different groups, such as intensive care unit patients, pediatric patients, and healthy subjects. Unlike conventional U-Net architectures, PPG2RespNet introduces layered skip connections, establishing hierarchical and dense connections for robust signal extraction. The bottleneck layer of the model is also modified to enhance the extraction of latent features. To evaluate PPG2RespNet's performance, we assessed its ability to reconstruct respiratory signals and estimate respiration rates. The model outperformed other models in signal-to-signal synthesis, achieving exceptional Pearson correlation coefficients (PCCs) with ground truth respiratory signals: 0.94 for BIDMC, 0.95 for VORTAL, and 0.96 for Capnobase. With mean absolute errors (MAE) of 0.69, 0.58, and 0.11 for the respective datasets, the model exhibited remarkable precision in estimating respiration rates. We used regression and Bland-Altman plots to analyze the predictions of the model in comparison to the ground truth. PPG2RespNet can thus obtain high-quality respiratory signals non-invasively, making it a valuable tool for calculating respiration rates., Competing Interests: Declarations. Conflict of interest: The authors declare no conflicts of interest for this study., (© 2024. Australasian College of Physical Scientists and Engineers in Medicine.)

Sulphated glycosaminoglycans (GAGs) such as heparin are a major component of mast cell granules and form the matrix within which biogenic mediators are stored. Since GAGs released from mast cells also play an important role in helminth expulsion, understanding GAG storage can offer new insights into mast cell function. Sodium butyrate (NaBu), a short-chain fatty acid, causes ultrastructural changes within the granules of human mast cells (HMC-1) and increases their histamine content. Therefore, we hypothesized that NaBu treatment would also modify the storage of polysaccharides such as GAGs. NaBu (1 mM) significantly increased GAG content and granularity in a time- and concentration-dependent manner without affecting cell viability and metabolic activity. NaBu increased the expression of enzymes associated with heparin biosynthesis ( GLCE , NDST1 , NDST2 , HS6ST1 , and GALT1 ) in a time-dependent manner. A cholesteryl butyrate emulsion (CholButE) increased heparin content after 24 and 48 h and modestly altered the expression of genes involved in heparin biosynthesis. Similar to NaBu, CholButE reduced cell proliferation without significantly altering viability or metabolic activity. These data show that butyrate increases the synthesis and storage of heparin in human mast cells, perhaps by altering their metabolic pathways.

This paper focuses on the feasibility of deep neural operator network (DeepONet) as a robust surrogate modeling method within the context of digital twin (DT) enabling technology for nuclear energy systems. Machine learning (ML)-based prediction algorithms that need extensive retraining for new reactor operational conditions may prohibit real-time inference for DT across varying scenarios. In this study, DeepONet is trained with possible operational conditions and that relaxes the requirement of continuous retraining - making it suitable for online and real-time prediction components for DT. Through benchmarking and evaluation, DeepONet exhibits remarkable prediction accuracy and speed, outperforming traditional ML methods, making it a suitable algorithm for real-time DT inference in solving a challenging particle transport problem. DeepONet also exhibits generalizability and computational efficiency as an efficient surrogate tool for DT component. However, the application of DeepONet reveals challenges related to optimal sensor placement and model evaluation, critical aspects of real-world DT implementation. Addressing these challenges will further enhance the method's practicality and reliability. Overall, this study marks an important step towards harnessing the power of DeepONet surrogate modeling for real-time inference capability within the context of DT enabling technology for nuclear systems., (© 2024. The Author(s).)

D'Ann Rochon passed away on November 29 th 2022. She is remembered for her outstanding contributions to the field of plant virology, her strong commitment to high quality science and her dedication to the training and mentorship of the next generation of scientists. She was a research scientist for Agriculture and Agri-Food Canada and an Adjunct Professor for the University of British Columbia. Her research program provided new insights on the infection cycle of tombusviruses and related viruses, including ground-breaking research on the structure of virus particles, the mechanisms of virus transmission by fungal zoospores, and the complexity of plant-virus interactions. She also developed diagnostic antibodies for plum pox virus and little cherry virus 2 that have had a significant impact on the management of these viruses., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Crown Copyright © 2023. Published by Elsevier Inc. All rights reserved.)

In this study, a new drug carrier based on gelled-oil nanoparticles (GNPs) was designed and synthesized for the encapsulation and release of the model hydrophobic drug, berberine chloride (BCl). Two compositions with different oil phases were examined, sesame oil (SO) and cinnamaldehyde (Cin), which were emulsified with water, stabilized with Tween 80 (Tw80), and gelled using an N-alkylated primary oxalamide low-molecular-weight gelator (LMWG) to give stable dispersions of GNPs between 100 and 200 nm in size. The GNP formulation with Cin was significantly favored over SO due to (1) lower gel melting temperatures, (2) higher gel mechanical strength, and (3) significantly higher solubility, encapsulation efficiency, and loading of BCl. Also, the solubility and loading of BCl in Cin were significantly increased (at least 7-fold) with the addition of cinnamic acid. In vitro release studies showed that the release of BCl from the GNPs was independent of gelator concentration and lower than that for BCl solution and the corresponding nanoemulsion (no LWMG). Also, cell internalization studies suggested that the N-alkylated primary oxalamide LMWG did not interfere with the internalization efficiency of BCl into mouse mast cells. Altogether, this work demonstrates the potential use of these new GNP formulations for biomedical studies involving the encapsulation of drugs and nutraceuticals and their controlled release., Competing Interests: The authors declare no competing financial interest., (Crown © 2023. Published by American Chemical Society.)

Mast cells initiate allergic inflammatory immune responses and play a role in disease by releasing various inflammatory and immunomodulatory mediators. Several mast cell-lines and primary cultured cells have been used as mast cell models with inconsistent results among research groups. Bone marrow-derived mast cells (BMMC) cultured from mouse bone marrow progenitor cells are often used as a representative model of mucosal mast cell behaviour, however their reported phenotype is variable due to inconsistent culture protocols. RBL-2H3 is a rat basophilic histamine-releasing cell line that has some characteristics of both mast cells and basophils but is not a true representation of either cell type. The murine mast cell line MC/9 is an IL-3-dependent mucosal mast cell model but has limited mast cell characteristics. In this study, we have compared the response of BMMC (derived from C57BL/6 male or female mice), two sources of RBL-2H3 (purchased directly from ATCC and a lab curated culture), and MC/9 (ATCC) at several critical stages to some common stimuli (IgE/Ag, A23187) and analyzed mast cell morphology, expression level of common mast cell surface markers (CD117 and FcεRI), protease expression, and function (growth kinetics, viability, ROS production, degranulation, cytokine release and FcεRI signaling). The objective of this study was to provide insight into the effects of culture conditions, biological sex, and age of the cells on variability among reported phenotypes and, to determine optimal conditions for activation of these cells. Our data show that factors that are often overlooked such as source, age and biological sex of mast cells play an integral role in phenotypic outcomes and may account for the reported variability in their function., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Inc.)

Introduction: Mast cells are highly granulated tissue-resident leukocytes that require a three-dimensional matrix to differentiate and mediate immune responses. However, almost all cultured mast cells rely on two-dimensional suspension or adherent cell culture systems, which do not adequately reflect the complex structure that these cells require for optimal function. Methods: Crystalline nanocellulose (CNC), consisting of rod-like crystals 4-15 nm in diameter and 0.2-1 µm in length, were dispersed in an agarose matrix (12.5% w/v), and bone marrow derived mouse mast cells (BMMC) were cultured on the agarose/CNC composite. BMMC were activated with the calcium ionophore A23187 or immunoglobulin E (IgE) and antigen (Ag) to crosslink high affinity IgE receptors (FcεRI). Results: BMMC cultured on a CNC/agarose matrix remained viable and metabolically active as measured by reduction of sodium 3'-[1-[(phenylamino)-carbony]-3,4-tetrazolium]-bis(4-methoxy-6-nitro) benzene-sulfonic acid hydrate (XTT), and the cells maintained their membrane integrity as analyzed by measuring the release of lactate dehydrogenase (LDH) and propidium iodide exclusion by flow cytometry. Culture on CNC/agarose matrix had no effect on BMMC degranulation in response to IgE/Ag or A23187. However, culture of BMMC on a CNC/agarose matrix inhibited A23187-and IgE/Ag-activated production of tumor necrosis factor (TNF) and other mediators such as IL-1β, IL-4, IL-6, IL-13, MCP-1/CCL2, MMP-9 and RANTES by as much as 95%. RNAseq analysis indicated that BMMC expressed a unique and balanced transcriptome when cultured on CNC/agarose. Discussion: These data demonstrate that culture of BMMCs on a CNC/agarose matrix promotes cell integrity, maintains expression of surface biomarkers such as FcεRI and KIT and preserves the ability of BMMC to release pre-stored mediators in response to IgE/Ag and A23187. However, culture of BMMC on CNC/agarose matrix inhibits BMMC production of de novo synthesized mediators, suggesting that CNC may be altering specific phenotypic characteristics of these cells that are associated with late phase inflammatory responses., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Kulka, Wagner, Cho, Alam, Santos, Jovel, Karamchand and Marcet-Palacios.)

Pillaring of synthetic layered crystalline silicates and aluminosilicates provides a strategy to enhance their adsorption and separation performance, and can facilitate the understanding of such behavior in more complex natural clays. We perform the first-principles density functional theory calculations for the pillaring of the pure silica polymorph of an MCM-22 type molecular sieve. Starting with a precursor material MCM-22P with fully hydroxylated layers, a pillaring agent, (EtO) 3 SiR, can react with hydroxyl groups (-OH) on adjacent internal surfaces, 2(-OH) + (EtO) 3 SiR + H 2 O → (-O) 2 SiOHR + 3EtOH, to form a pillar bridging these surfaces, or with a single hydroxyl, -OH + (EtO) 3 SiR + 2H 2 O → (-O)Si(OH) 2 R + 3EtOH, grafting to one surface. For computational efficiency, we replace the experimental organic ligand, R, by a methyl group. We find that the interlayer spacing in MCM-22 is reduced by 2.66 Å relative to weakly bound layers in the precursor MCM-22P. Including (-O) 2 SiR bridges for 50% (100%) of the hydroxyl sites in MCM-22P increases the interlayer spacing relative to MCM-22 by 2.52 Å (2.46 Å). For comparison, we also analyze the system where all -OH groups in MCM-22P are replaced by non-bridging grafted (-O)Si(OH) 2 R which results in a smaller interlayer spacing expansion of 2.17 Å relative to MCM-22. Our results for the interlayer spacing in the pillared materials are compatible with experimental observations for a similar MCM-22 type material with low Al content (Si : Al = 51 : 1) of an expansion relative to MCM-22 of roughly 2.8 Å and 2.5 Å from our x-ray diffraction and scanning transmission electron microscopy analyses, respectively. The latter analysis reveals significant variation in individual layer spacings.

Mast cells (MCs), are hematopoetically-derived secretory immune cells that release preformed as well as de novo synthesized inflammatory mediators in response to activation by several stimuli. Based on their role in inflammatory responses, particularly in the lung and skin, MCs provide an effective target for anti-inflammatory therapeutic strategies. Drug-delivery of lipophilic payloads to MCs can be challenging due to their functionally distinct intracellular structures. In the present study, pH-sensitive cationic lipid-based nanoparticles (LNPs) composed of DODMA, DODAP or DOTAP lipids that encapsulated a GFP or eGFP plasmid were constructed using non-turbulent microfluidic mixing. This approach achieved up to 75-92% encapsulation efficiency. Dynamic light scattering revealed a uniformly sized and homogeneous dispersion of LNPs. To promote cellular internalization, LNPs were complexed with apolipoproteins, amphipathic proteins capable of binding lipids and facilitating their transport into cells. Cryo-TEM analysis showed that LNP structure was differentially modified when associated with different types of apolipoproteins. LNP preparations made up of DODMA or DODMA, DODAP and DOTAP lipids were coated with seven apolipoproteins (Apo A1, B, C3, D, E2, E4 and H). Differentiated bone-marrow derived mouse mast cells (BMMCs) were exposed to apolipoprotein-LNP and internalization was measured using flow cytometry. Out of all the apolipoproteins tested, ApoC3 most efficiently facilitated cellular internalization of the LNP into BMMCs as determined by GFP fluorescence using flow cytometry. These effects were confirmed in a less differentiated but also interleukin-3-dependent model of mouse mast cells, MC/9. ApoC3-LNP enhanced internalization by BMMC in a concentration-dependent manner and this was significantly increased when BMMC were pre-treated with inhibitors of actin polymerization, suggesting a dependence on intracellular shuttling. Activation of peroxisome proliferator-activated receptor gamma (PPARγ) decreased ApoC3-LNP internalization and reduced the expression of apolipoprotein E receptor 2 (ApoER2), suggesting that ApoC3-LNP binding to ApoER2 may be responsible for its enhanced internalization. Furthermore, ApoC3 fails to facilitate internalization of LNPs in Lrp8 -/- KO BMMC that do not express ApoER2 on their cell surface. Altogether, our studies reveal an important role of ApoC3 in facilitating internalization of cationic LNPs into MCs., (© 2023. Crown.)

Mast cells (MC) synthesize and store proinflammatory mediators and are centrally important in atopic diseases such as asthma and atopic dermatitis. Quercetin a and resveratrol are plant derived polyphenolic compounds with anti-inflammatory properties that inhibit MC degranulation and mediator release. However, the underlying mechanism of these inhibitory effects on MC is poorly understood and it is unclear whether this is a general effect on all MC phenotypes. We have characterized and compared the effects of quercetin with resveratrol on human (LAD2) and mouse (MC/9 and BMMC) MC mediator release, receptor expression and FcεRI signaling to better understand the mechanisms involved in quercetin and resveratrol-mediated inhibition of MC activation. Quercetin significantly decreased the expression of FcεRI by BMMC and MC/9, although the effects on MC/9 were associated with a significant reduction in cell viability. Quercetin also inhibited antigen-stimulated TNF release by BMMC. Although neither quercetin nor resveratrol significantly altered antigen-stimulated BMMC degranulation or downstream signaling events such as phosphorylation of spleen tyrosine kinase (SYK) or extracellular signal-regulated kinase 1/2 (ERK), resveratrol inhibited ERK phosphorylation and FcεRI- stimulated degranulation in LAD2. Our data suggests that quercetin and resveratrol inhibit human and mouse MC differentially and that these effects are associated with modification of FcεRI expression, signaling (phosphorylation of SYK and ERK) and mediator release.

Nanocapsules are hollow nanoscale shells that have applications in drug delivery, batteries, self-healing materials, and as model systems for naturally occurring shell geometries. In many applications, nanocapsules are designed to release their cargo as they buckle and collapse, but the details of this transient buckling process have not been directly observed. Here, we use in situ liquid-phase transmission electron microscopy to record the electron-irradiation-induced buckling in spherical 60-187 nm polymer capsules with ∼3.5 nm walls. We observe in real time the release of aqueous cargo from these nanocapsules and their buckling into morphologies with single or multiple indentations. The in situ buckling of nanoscale capsules is compared to ex situ measurements of collapsed and micrometer-sized capsules and to Monte Carlo (MC) simulations. The shape and dynamics of the collapsing nanocapsules are consistent with MC simulations, which reveal that the excessive wrinkling of nanocapsules with ultrathin walls results from their large Föppl-von Kármán numbers around 10 5 . Our experiments suggest design rules for nanocapsules with the desired buckling response based on parameters such as capsule radius, wall thickness, and collapse rate.

Sesquiterpenes (SQs) are volatile compounds made by plants, insects, and marine organisms. SQ have a large range of biological properties and are potent inhibitors and modulators of inflammation, targeting specific components of the nuclear factor-kappaB (NF-κB) signaling pathway and nitric oxide (NO) generation. Because SQs can be isolated from over 1600 genera and 2500 species grown worldwide, they are an attractive source of phytochemical therapeutics. The chemical structure and biosynthesis of SQs is complex, and the SQ scaffold represents extraordinary structural variety consisting of both acyclic and cyclic (mono, bi, tri, and tetracyclic) compounds. These structures can be decorated with a diverse range of functional groups and substituents, generating many stereospecific configurations. In this review, the effect of SQs on inflammation will be discussed in the context of their complex chemistry. Because inflammation is a multifactorial process, we focus on specific aspects of inflammation: the inhibition of NF-kB signaling, disruption of NO production and modulation of dendritic cells, mast cells, and monocytes. Although the molecular targets of SQs are varied, we discuss how these pathways may mediate the effects of SQs on inflammation.

Objective and Design: Drug delivery to inflammatory cells is dependent upon poorly understood, complex endocytic processes. Berberine (BBR), a benzylisoquinoline alkaloid, binds to heparin and targets glycosaminoglycan-rich granules in mast cells (MC), but the mechanism of BBR internalization is unknown., Methods: BMMC were treated with various concentrations of BBR for different amounts of time and BBR internalization was assessed by flow cytometry and fluorescence microscopy. BMMC were pretreated with endocytic inhibitors or a growth factor (IL-3) prior to BBR exposure to access mechanisms of its internalization., Results: After 24 h, 48 ± 0.8% of BMMC internalized BBR and this process was dependent upon temperature and the presence of glucose in the medium. Methanol fixation reduced BBR internalization, suggesting the involvement of an energy-dependent active transport mechanism. To determine mode of internalization, BBR was encapsulated into Lipofectamine TM lipoplexes since these are known to circumvent classical endocytic pathways. Incorporating BBR into lipoplexes decreased BBR internalization by 26% and 10% (10 μg/ml and 100 μg/ml Lipo-BBR respectively) by BMMC. BBR endocytosis was significantly reduced by Latrunculin B (88%), Cytochalasin B (87%), Chloroquine (86.5%) and 3-methyladenine (91%), indicating that actin polymerization, lysosomal pH and lysosomal self-degradation via the autophagy pathway was involved. In contrast, IL-3 treatment significantly enhanced BBR endocytosis (54% by 40 ng/ml IL-3) suggesting that IL-3 signaling pathways play a role in internalization., Conclusions: Our data suggests that internalization of BBR by resting and IL-3-activated BMMC utilizes an energy-dependent pathway that is dependent upon glucose metabolism and temperature. Furthermore, this process requires actin polymerization and lysosomal trafficking. These data suggest internalization of benzylisoquinoline compounds is an active and complex process., (© 2022. Crown.)

Laser-assisted atom probe tomography (APT) is a relatively new, powerful technique for sub-nanometric mineral and biomineral analysis. However, the laser-assisted APT analysis of highly anisotropic and chemically diverse minerals, such as phyllosilicates, may prove especially challenging due to the complex interaction between the crystal structure and the laser pulse upon applying a high electric field. Micas are a representative group of nonswelling clay minerals of relevance to a number of scientific and technological fields. In this study, a Mg-rich biotite was analyzed by APT to generate preliminary data on nonisotropic minerals and to investigate the effect of the crystallographic orientation on mica chemical composition and structure estimation. The difference in results obtained for specimens extracted from the (001) and (hk0) mica surfaces indicate the importance of both experimental parameters and the crystallography. Anisotropy of mica has a strong influence on the physicochemical properties of the mineral during field evaporation and the interpretation of APT data. The promising results obtained in the present study open the way to future innovative APT applications on mica and clay minerals and contribute to the general discussion on the challenges for the analysis of geomaterials by atom probe tomography.

Three-dimensional (3D) bioprinting utilizes hydrogel-based composites (or biomaterial inks) that are deposited in a pattern, forming a substrate onto which cells are deposited. Because many biomaterial inks can be potentially cytotoxic to primary cells, it is necessary to determine the biocompatibility of these hydrogel composites prior to their utilization in costly 3D tissue engineering processes. Some 3D culture methods, including bioprinting, require that cells be embedded into a 3D matrix, making it difficult to extract and analyze the cells for changes in viability and biomarker expression without eliciting mechanical damage. This protocol describes as proof of concept, a method to assess the biocompatibility of a crystalline nanocellulose (CNC) embedded agarose composite, fabricated into a 24-well culture system, with mouse bone marrow-derived mast cells (BMMCs) using flow cytometric assays for cell viability and biomarker expression. After 18 h of exposure to the CNC/agarose/D-mannitol matrix, BMMC viability was unaltered as measured by propidium iodide (PI) permeability. However, BMMCs cultured on the CNC/agarose/D-mannitol substrate appeared to slightly increase their expression of the high-affinity IgE receptor (FcεRI) and the stem cell factor receptor (Kit; CD117), although this does not appear to be dependent on the amount of CNC in the bioink composite. The viability of BMMCs was also assessed following a time course exposure to hydrogel scaffolds that were fabricated from a commercial biomaterial ink composed of fibrillar nanocellulose (FNC) and sodium alginate using a 3D extrusion bioprinter. Over a period of 6-48 h, the FNC/alginate substrates did not adversely affect the viability of the BMMCs as determined by flow cytometry and microtiter assays (XTT and lactate dehydrogenase). This protocol describes an efficient method to rapidly screen the biochemical compatibility of candidate biomaterial inks for their utility as 3D scaffolds for post-print seeding with mast cells.

The coronavirus disease 2019 (COVID-19), a serious respiratory illness caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has emerged as a global pandemic. Canada reported its first case of COVID-19 on the 25th January 2020. By March 2020, the virus had spread within Canadian communities reaching the most frail and vulnerable elderly population in long-term care facilities. The majority of cases were reported in the provinces of Quebec, Ontario, Alberta, and British Columbia, and the highest mortality was seen among individuals aged 65 years or older. Canada has the highest prevalence and incidence rates of several chronic inflammatory diseases, such as multiple sclerosis, inflammatory bowel disease, and Parkinson's disease. Many elderly Canadians also live with comorbid medical illnesses, such as hypertension, diabetes, cardiovascular disease, and chronic lung disease, and are more likely to suffer from severe COVID-19 with a poor prognosis. It is becoming increasingly evident that underlying inflammatory disease contributes to the pathogenesis of SARS-CoV-2. Here, we review the mechanisms behind SARS-CoV-2 infection, and the host inflammatory responses that lead to resolution or progression to severe COVID-19 disease. Furthermore, we discuss the landscape of COVID-19 therapeutics that are currently in development in Canada.

Syzygium fruticosum (SF), a valuable Bangladeshi fruit, is considered an alternative therapeutic agent. Mainly, seeds are used as nutritional phytotherapy to ease physical and mental status by preventing chronic diseases. Here, we scrutinized the S. fruticosum seed's fundamental importance in traditional medicine by following an integrated approach combining in vivo, in vitro, and in silico studies. The SF was fractionated with different solvents, and the ethyl acetate fraction of SF (EaF-SF) was further studied. Mice treated with EaF-SF (200 and 400 mg/kg) manifested anxiolysis evidenced by higher exploration in elevated plus maze and hole board tests. Similarly, a dose-dependent drop of immobility time in a forced swimming test ensured significant anti-depressant activity. Moreover, higher dose treatment exposed reduced exploratory behaviour resembling decreased movement and prolonged sleeping latency with a quick onset of sleep during the open field and thiopental-induced sleeping tests, respectively. In parallel, EaF-SF significantly ( p < 0.001) and dose-dependently suppressed acetic acid and formalin-induced pain in mice. Also, a noteworthy anti-inflammatory activity and a substantial ( p < 0.01) clot lysis activity (thrombolytic) was observed. Gas chromatography-mass spectrometry (GC-MS) analysis resulted in 49 bioactive compounds. Among them, 12 bioactive compounds with Lipinski's rule and safety confirmation showed strong binding affinity (molecular docking) against the receptors of each model used. To conclude, the S. fruticosum seed is a prospective source of health-promoting effects that can be an excellent candidate for preventing degenerative diseases.

Cucumber necrosis virus (CNV) is a (+)ssRNA virus that elicits spreading local and systemic necrosis in Nicotiana benthamiana. We previously showed that the CNV coat protein (CP) arm functions as a chloroplast transit peptide that targets a CP fragment containing the S and P domains to chloroplasts during infection. Here we show that several CP arm mutants that inefficiently target chloroplasts, along with a mutant that lacks the S and P domains, show an early onset of more localized necrosis along with protracted induction of pathogenesis related protein (PR1a). Agroinfiltrated CNV CP is shown to interfere with CNV p33 and Tomato bushy stunt virus p19 induced necrosis. Additionally, we provide evidence that a CP mutant that does not detectably enter the chloroplast stroma induces relatively higher levels of several plant defense-related genes compared to WT CNV. Together, our data suggest that targeting of CNV CP to the chloroplast stroma interferes with chloroplast-mediated plant defense., (Crown Copyright © 2020. Published by Elsevier Inc. All rights reserved.)

Correlating the structure and composition of nanowires grown by the vapour-liquid-solid (VLS) mechanism with their electrical properties is essential for designing nanowire devices. In situ transmission electron microscopy (TEM) that can image while simultaneously measuring the current-voltage (I-V) characteristics of individual isolated nanowires is a unique tool for linking changes in structure with electronic transport. Here we grow and electrically connect silicon nanowires inside a TEM to perform in situ electrical measurements on individual nanowires both at high temperature and upon surface oxidation, as well as under ambient conditions. As-grown, the oxide-free nanowires have nonlinear I-V characteristics. We analyse the I-V measurements in terms of both bulk and injection limited transport models, finding Joule heating effects, bulk-limiting effects for thin nanowires and an injection-limiting effect for thick wires when high voltages are applied. When the nanowire surface is modified by in situ oxidation, drastic changes occur in the electronic properties. We investigate the relation between the observed geometry, changes in the surface structure and changes in electronic transport, obtaining information for individual nanowires that is inaccessible to other measuring techniques.

n-3 polyunsaturated fatty acids (PUFA) influences a variety of disease conditions, such as hypertension, heart disease, diabetes, cancer and allergic diseases, by modulating membrane constitution, inhibiting production of proinflammatory eicosanoids and cytokines, and binding to cell surface and nuclear receptors. We have previously shown that n-3 PUFA inhibit mast cell functions by disrupting high affinity IgE receptor (FcεRI) lipid raft partitioning and subsequent suppression of FcεRI signaling in mouse bone marrow-derived mast cells. However, it is still largely unknown how n-3 PUFA modulate human mast cell function, which could be attributed to multiple mechanisms. Using a human mast cell line (LAD2), we have shown similar modulating effects of n-3 PUFA on FcεRI lipid raft shuttling, FcεRI signaling, and mediator release after cell activation through FcεRI. We have further shown that these effects are at least partially associated with ligation of G protein-coupled receptor 120 expressed on LAD2 cells. This observation has advanced our mechanistic knowledge of n-3 PUFA's effect on mast cells and demonstrated the interplay between n-3 PUFA, lipid rafts, FcεRI, and G protein-coupled receptor 120. Future research in this direction may present new targets for nutritional intervention and therapeutic agents., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2020 Wang, Ilarraza, Tancowny, Alam and Kulka.)

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a highly contagious respiratory disease referred to as COVID-19. However, emerging evidence indicates that a small but growing number of COVID-19 patients also manifest neurological symptoms, suggesting that SARS-CoV-2 may infect the nervous system under some circumstances. SARS-CoV-2 primarily enters the body through the epithelial lining of the respiratory and gastrointestinal tracts, but under certain conditions this pleiotropic virus may also infect peripheral nerves and gain entry into the central nervous system (CNS). The brain is shielded by various anatomical and physiological barriers, most notably the blood-brain barrier (BBB) which functions to prevent harmful substances, including pathogens and pro-inflammatory mediators, from entering the brain. The BBB is composed of highly specialized endothelial cells, pericytes, mast cells and astrocytes that form the neurovascular unit, which regulates BBB permeability and maintains the integrity of the CNS. In this review, potential routes of viral entry and the possible mechanisms utilized by SARS-CoV-2 to penetrate the CNS, either by disrupting the BBB or infecting the peripheral nerves and using the neuronal network to initiate neuroinflammation, are briefly discussed. Furthermore, the long-term effects of SARS-CoV-2 infection on the brain and in the progression of neurodegenerative diseases known to be associated with other human coronaviruses are considered. Although the mechanisms of SARS-CoV-2 entry into the CNS and neurovirulence are currently unknown, the potential pathways described here might pave the way for future research in this area and enable the development of better therapeutic strategies., (© 2020 Her Majesty the Queen in Right of Canada. European Journal of Neurology © 2020 European Academy of Neurology.)

Liquid cell transmission electron microscopy (TEM) enables the direct observation of dynamic physical and chemical processes in liquids at the nanoscale. Quantitative investigations into reactions with fast kinetics and/or multiple reagents will benefit from further advances in liquid cell design that facilitate rapid in situ mixing and precise control over reagent volumes and concentrations. This work reports the development of inorganic-organic nanocapsules for high-resolution TEM imaging of nanoscale reactions in liquids with well-defined zeptoliter volumes. These hybrid nanocapsules, with 48 nm average diameter, consist of a thin layer of gold coating a lipid vesicle. As a model reaction, the nucleation, growth, and diffusion of nanobubbles generated by the radiolysis of water is investigated inside the nanocapsules. When the nanobubbles are sufficiently small (10-25 nm diameter), they are mobile in the nanocapsules, but their movement deviates from Brownian motion, which may result from geometric confinement by the nanocapsules. Gases and fluids can be transported between two nanocapsules when they fuse, demonstrating in situ mixing without using complex microfluidic schemes. The ability to synthesize nanocapsules with controlled sizes and to monitor dynamics simultaneously inside multiple nanocapsules provides opportunities to investigate nanoscale processes such as single nanoparticle synthesis in confined volumes and biological processes such as biomineralization and membrane dynamics.

Multidrug resistant (MDR) Salmonella are a leading cause of foodborne diseases and serious human health concerns worldwide. In this study we detected MDR Salmonella in broiler chicken along with the resistance genes and class 1 integron gene intl1 . A total of 100 samples were collected from broiler farms comprising 50 cloacal swabs, 35 litter and 15 feed samples. Overall prevalence of Salmonella was 35% with the highest detected in cloacal swabs. Among the Salmonella , 30 isolates were confirmed as S. enterica serovar Typhimurium using molecular methods of PCR. Disk diffusion susceptibility test revealed that all the Salmonella were classified as MDR with the highest resistance to tetracycline (97.14%), chloramphenicol (94.28%), ampicillin (82.85%) and streptomycin (77.14%). The most prevalent resistance genotypes were tetA (97.14%), floR (94.28%), bla TEM-1 (82.85%) and aadA1 (77.14%). In addition, among the MDR Salmonella, 20% were positive for class 1 integron gene ( intl1) . As far as we know, this is the first study describing the molecular basis of antibiotic resistance in MDR Salmonella from broiler farms in Bangladesh. In addition to tetA, floR, bla TEM-1 , aadA1 and intl1 were also detected in the isolated MDR Salmonella. The detection of MDR Salmonella in broiler chicken carrying intl1 is of serious public health concern because of their zoonotic nature and possibilities to enter into the food chain.

Concerns about the effects of global warming provide a strong case to consider how best nuclear power could be applied to marine propulsion. Currently, there are persistent efforts worldwide to combat global warming, and that also includes the commercial freight shipping sector. In an effort to decarbonize the marine sector, there are growing interests in replacing the contemporary, traditional propulsion systems with nuclear propulsion systems. The latter system allows freight ships to have longer intervals before refueling; subsequently, lower fuel costs, and minimal carbon emissions. Nonetheless, nuclear propulsion systems have remained largely confined to military vessels. It is highly desirable that a civil marine core not use soluble boron for reactivity control, but it is then a challenge to achieve an adequate shutdown margin throughout the core life while maintaining reactivity control and acceptable power distributions in the core. High-thickness ZrB 2 150 μm Integral Fuel Burnable Absorber (IFBA) is an excellent burnable poison (BP) candidate for long life soluble-boron-free core. However, in this study, we want to minimize the use of 150 μm IFBA since B-10 undergoes an (n, α) capture reaction, and the resulting helium raises the pressure within the plenum and in the cladding. Therefore, we have considered several alternative and novel burnable BP design strategies to minimize the use of IFBA for reactivity control in this study: (Case 1) a composite BP: gadolinia (Gd 2 O 3 ) or erbia (Er 2 O 3 ) with 150 μm thickness ZrB 2 IFBA; (Case 2) Pu-240 or Am-241 mixed homogeneously with the fuel; and (Case 3) another composite BP: Pu-240 or Am-241 with 150 μm thickness ZrB 2 IFBA. The results are compared against those for a high-thickness 150 μm 25 IFBA pins design from a previous study. The high-thickness 150 μm 25 IFBA pins design is termed the "IFBA-only" BP design throughout this study. We arrive at a design using 15% U-235 fuel loaded into 13 × 13 assemblies with Case 3 BPs (IFBA+Pu-240 or IFBA+Am-241) for reactivity control while reducing 20% IFBA use. This design exhibits lower assembly reactivity swing and minimal burnup penalty due to the self-shielding effect. Case 3 provides ~10% more initial (beginning-of-life) reactivity suppression with ~70% less reactivity swing compared to the IFBA-only design for UO 2 fuel while achieving almost the same core lifetime. Finally, optimized Case 3 assemblies were loaded in 3D nodal diffusion and reactor model code. The results obtained from the 3D reactor model confirmed that the designed core with the proposed Case 3 BPs can achieve the target lifetime of 15 years while contributing to ~10% higher BOL reactivity suppression, ~70% lower reactivity swings, ~30% lower radial form factor and ~28% lower total peaking factor compared to the IFBA-only core.

A 62-year-old man presented with a 2-year history of syncope, collapse and fluctuating blood pressure (BP). His medications included midodrine (10 mg, three times per day) and fludrocortisone (0.1 mg, two times per day), but neither treatment afforded symptomatic relief. Autonomic testing was performed. Head-up tilt table testing revealed a supine BP of 112/68 mm Hg (heart rate, 74 beats per minute (bpm)) after 6 min, which dropped to 76/60 mm Hg (83 bpm) within 2 min of 80° head-up tilt. Findings from a heart rate with deep breathing test and a Valsalva test were consistent with autonomic dysfunction. The patient was diagnosed with neurogenic orthostatic hypotension and treated with droxidopa (100 mg, two times per day; titrated to 100 mg, one time per day). After initiating treatment with droxidopa, the patient no longer reported losing consciousness on standing and experienced improvement in activities of daily living. These improvements were maintained through 1 year of follow-up., Competing Interests: Competing interests: SBA received support from Lundbeck for travel and registration fees. WA has nothing to disclose. AS has received honoraria for serving on advisory boards for Lundbeck., (© BMJ Publishing Group Limited 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Recent advances in graphene liquid cells for in situ transmission electron microscopy (TEM) have opened many opportunities for the study of materials transformations and chemical reactions in liquids with high spatial resolution. However, the behavior of thin liquids encapsulated in a graphene liquid cell has not been fully understood. Here, we report real time TEM imaging of the nanoscale dynamic behavior of liquids in graphene nanocapillaries. Our observations reveal that the interfaces between liquid and gas bubble can fluctuate, leading to the generation of liquid nanodroplets near the interfaces. Liquid nanodroplets often show irregular shape with dynamic changes of their configuration under the electron beam. We consider that the dynamic motion of liquid-gas interfaces might be introduced by the electrostatic energy from transiently charged interfaces. We find that improving the wettability of graphene liquid cells by ultraviolet-ozone treatment can significantly modify the dynamic motion of the encapsulated liquids. Our study provides valuable information of the interactions between liquid and graphene under the electron beam, and it also offers key insights on the nanoscale fluid dynamics in confined spaces., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Cucumber necrosis virus (CNV) is a T = 3 icosahedral virus with a (+)ssRNA genome. The N-terminal CNV coat protein arm contains a conserved, highly basic sequence ("KGRKPR"), which we postulate is involved in RNA encapsidation during virion assembly. Seven mutants were constructed by altering the CNV "KGRKPR" sequence; the four basic residues were mutated to alanine individually, in pairs, or in total. Virion accumulation and vRNA encapsidation were significantly reduced in mutants containing two or four substitutions and virion morphology was also affected, where both T = 1 and intermediate-sized particles were produced. Mutants with two or four substitutions encapsidated significantly greater levels of truncated RNA than that of WT, suggesting that basic residues in the "KGRKPR" sequence are important for encapsidation of full-length CNV RNA. Interestingly, "KGRKPR" mutants also encapsidated relatively higher levels of host RNA, suggesting that the "KGRKPR" sequence also contributes to selective encapsidation of CNV RNA., (Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.)

The transcription factor Atf1 is known to promote cell survival during various stress conditions in Schizosaccharomyces pombe by activating the expression of appropriate genes. It can also activate transcription of other important genes responsible for cell cycle progression. An Atf1-dependent increase in the expression of cell division promoting genes will oppose activation of checkpoints necessary to ensure repairs and cell survival during stress. Hence, selective inhibition of the cell cycle-related functions of Atf1 would be indispensable for cellular survival during stress. Here we present evidence in favour of selective inhibition of Atf1's ability to activate cdc13+ transcription. We show that the transcription factor Pcr1 can specifically inhibit the recruitment of Atf1 on cdc13 promoter and thereby prevent Atf1-mediated mitotic acceleration. We also show that this opposition of Atf1 functions by Pcr1 extends to the G1-S transition event as well. Altogether these results suggest a previously unknown antagonistic function of Atf1 and Pcr1 in regulating Cdc13 expression during cell cycle progression., (© FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Uncoating of a virus particle to expose its nucleic acid is a critical aspect of the viral multiplication cycle, as it is essential for the establishment of infection. In the present study, we investigated the role of plant HSP70 homologs in the uncoating process of Cucumber necrosis virus (CNV), a nonenveloped positive-sense single-stranded RNA [(+)ssRNA] virus having a T=3 icosahedral capsid. We have found through Western blot analysis and mass spectrometry that the HSP70 homolog Hsc70-2 copurifies with CNV particles. Virus overlay and immunogold labeling assays suggest that Hsc70-2 is physically bound to virions. Furthermore, trypsin digestion profiles suggest that the bound Hsc70-2 is partially protected by the virus, indicating an intimate association with particles. In investigating a possible role of Hsc70-2 in particle disassembly, we showed that particles incubated with Hsp70/Hsc70 antibody produce fewer local lesions than those incubated with prebleed control antibody on Chenopodium quinoa In conjunction, CNV virions purified using CsCl and having undetectable amounts of Hsc70-2 produce fewer local lesions. We also have found that plants with elevated levels of HSP70/Hsc70 produce higher numbers of local lesions following CNV inoculation. Finally, incubation of recombinant Nicotiana benthamiana Hsc70-2 with virus particles in vitro leads to conformational changes or partial disassembly of capsids as determined by transmission electron microscopy, and particles are more sensitive to chymotrypsin digestion. This is the first report suggesting that a cellular Hsc70 chaperone is involved in disassembly of a plant virus., Importance: Virus particles must disassemble and release their nucleic acid in order to establish infection in a cell. Despite the importance of disassembly in the ability of a virus to infect its host, little is known about this process, especially in the case of nonenveloped spherical RNA viruses. Previous work has shown that host HSP70 homologs play multiple roles in the CNV infection cycle. We therefore examined the potential role of these cellular components in the CNV disassembly process. We show that the HSP70 family member Hsc70-2 is physically associated with CNV virions and that HSP70 antibody reduces the ability of CNV to establish infection. Statistically significantly fewer lesions are produced when virions having undetectable HSc70-2 are used as an inoculum. Finally incubation of Hsc70-2 with CNV particles results in conformational changes in particles. Taken together, our data point to an important role of the host factor Hsc70-2 in CNV disassembly., (© Crown copyright 2017.)

Semiconductor nanowires with precisely controlled structure, and hence well-defined electronic and optical properties, can be grown by self-assembly using the vapour-liquid-solid process. The structure and chemical composition of the growing nanowire is typically determined by global parameters such as source gas pressure, gas composition and growth temperature. Here we describe a more local approach to the control of nanowire structure. We apply an electric field during growth to control nanowire diameter and growth direction. Growth experiments carried out while imaging within an in situ transmission electron microscope show that the electric field modifies growth by changing the shape, position and contact angle of the catalytic droplet. This droplet engineering can be used to modify nanowires into three dimensional structures, relevant to a range of applications, and also to measure the droplet surface tension, important for quantitative development of strategies to control nanowire growth.

Unlabelled: RNA viruses often depend on host factors for multiplication inside cells due to the constraints of their small genome size and limited coding capacity. One such factor that has been exploited by several plant and animal viruses is heat shock protein 70 (HSP70) family homologs which have been shown to play roles for different viruses in viral RNA replication, viral assembly, disassembly, and cell-to-cell movement. Using next generation sequence analysis, we reveal that several isoforms of Hsp70 and Hsc70 transcripts are induced to very high levels during cucumber necrosis virus (CNV) infection of Nicotiana benthamiana and that HSP70 proteins are also induced by at least 10-fold. We show that HSP70 family protein homologs are co-opted by CNV at several stages of infection. We have found that overexpression of Hsp70 or Hsc70 leads to enhanced CNV genomic RNA, coat protein (CP), and virion accumulation, whereas downregulation leads to a corresponding decrease. Hsc70-2 was found to increase solubility of CNV CP in vitro and to increase accumulation of CNV CP independently of viral RNA replication during coagroinfiltration in N. benthamiana. In addition, virus particle assembly into virus-like particles in CP agroinfiltrated plants was increased in the presence of Hsc70-2. HSP70 was found to increase the targeting of CNV CP to chloroplasts during infection, reinforcing the role of HSP70 in chloroplast targeting of host proteins. Hence, our findings have led to the discovery of a highly induced host factor that has been co-opted to play multiple roles during several stages of the CNV infection cycle., Importance: Because of the small size of its RNA genome, CNV is dependent on interaction with host cellular components to successfully complete its multiplication cycle. We have found that CNV induces HSP70 family homologs to a high level during infection, possibly as a result of the host response to the high levels of CNV proteins that accumulate during infection. Moreover, we have found that CNV co-opts HSP70 family homologs to facilitate several aspects of the infection process such as viral RNA, coat protein and virus accumulation. Chloroplast targeting of the CNV CP is also facilitated, which may aid in CNV suppression of host defense responses. Several viruses have been shown to induce HSP70 during infection and others to utilize HSP70 for specific aspects of infection such as replication, assembly, and disassembly. We speculate that HSP70 may play multiple roles in the infection processes of many viruses., (Copyright © 2016, American Society for Microbiology. All Rights Reserved.)

The formation of self-assembled contacts between vapor-liquid-solid grown silicon nanowires and flat silicon surfaces was imaged in situ using electron microscopy. By measuring the structural evolution of the contact formation process, we demonstrate how different contact geometries are created by adjusting the balance between silicon deposition and Au migration. We show that electromigration provides an efficient way of controlling the contact. The results point to novel device geometries achieved by direct nanowire growth on devices.

Tombusviruses replicate on pre-existing organelles such as peroxisomes or mitochondria, the membranes of which become extensively reorganized into multivesicular bodies (MVBs) during the infection process. Cucumber necrosis virus (CNV) has previously been shown to replicate in association with peroxisomes in yeast. We show that CNV induces MVBs from peroxisomes in infected plants and that GFP-tagged p33 auxiliary replicase protein colocalizes with YFP(SKL), a peroxisomal marker. Most remarkably, the ER of CNV infected Nicotiana benthamiana 16C plants undergoes a dramatic reorganization producing numerous new peroxisome-like structures that associate with CNV p33, thus likely serving as a new site for viral RNA replication. We also show that plants agroinfiltrated with p33 develop CNV-like necrotic symptoms which are associated with increased levels of peroxide. Since peroxisomes are a site for peroxide catabolism, and peroxide is known to induce plant defense responses, we suggest that dysfunctional peroxisomes contribute to CNV induced necrosis., (Copyright © 2014. Published by Elsevier Inc.)