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Callose, a β‐1,3‐glucan plant cell wall polymer, regulates symplasmic channel size at plasmodesmata (PD) and plays a crucial role in a variety of plant processes. However, elucidating the molecular mechanism of PD callose homeostasis is limited. We screened and identified an Arabidopsis mutant plant with excessive callose deposition at PD and found that the mutated gene was α1‐COP, a member of the coat protein I (COPI) coatomer complex. We report that loss of function of α1‐COP elevates the callose accumulation at PD by affecting subcellular protein localization of callose degradation enzyme PdBG2. This process is linked to the functions of ERH1, an inositol phosphoryl ceramide synthase, and glucosylceramide synthase through physical interactions with the α1‐COP protein. Additionally, the loss of function of α1‐COP alters the subcellular localization of ERH1 and GCS proteins, resulting in a reduction of GlcCers and GlcHCers molecules, which are key sphingolipid (SL) species for lipid raft formation. Our findings suggest that α1‐COP protein, together with SL modifiers controlling lipid raft compositions, regulates the subcellular localization of GPI‐anchored PDBG2 proteins, and hence the callose turnover at PD and symplasmic movement of biomolecules. Our findings provide the first key clue to link the COPI‐mediated intracellular trafficking pathway to the callose‐mediated intercellular signaling pathway through PD. [ABSTRACT FROM AUTHOR]

Pathogens generate and secrete effector proteins to the host plant cells during pathogenesis to promote virulence and colonization. If the plant carries resistance (R) proteins that recognize pathogen effectors, effector‐triggered immunity (ETI) is activated, resulting in a robust immune response and hypersensitive response (HR). The bipartite effector AvrRps4 from Pseudomonas syringae pv. pisi has been well studied in terms of avirulence function. In planta, AvrRps4 is processed into two parts. The C‐terminal fragment of AvrRps4 (AvrRps4C) induces HR in turnip and is recognized by the paired resistance proteins AtRRS1/AtRPS4 in Arabidopsis. Here, we show that AvrRps4C targets a group of Arabidopsis WRKY, including WRKY46, WRKY53, WRKY54, and WRKY70, to induce its virulence function. Indeed, AvrRps4C suppresses the general binding and transcriptional activities of immune‐positive regulator WRKY54 and WRKY54‐mediated resistance. AvrRps4C interferes with WRKY54's binding activity to target gene SARD1 in vitro, suggesting WRKY54 is sequestered from the SARD1 promoter by AvrRps4C. Through the interaction of AvrRps4C with four WRKYs, AvrRps4 enhances the formation of homo‐/heterotypic complexes of four WRKYs and sequesters them in the cytoplasm, thus inhibiting their function in plant immunity. Together, our results provide a detailed virulence mechanism of AvrRps4 through its C‐terminus. [ABSTRACT FROM AUTHOR]

Summary: Plant pathogens destroy crops and cause severe yield losses, leading to an insufficient food supply to sustain the human population. Apart from relying on natural plant immune systems to combat biological agents or waiting for the appropriate evolutionary steps to occur over time, researchers are currently seeking new breakthrough methods to boost disease resistance in plants through genetic engineering. Here, we summarize the past two decades of research in disease resistance engineering against an assortment of pathogens through modifying the plant immune components (internal and external) with several biotechnological techniques. We also discuss potential strategies and provide perspectives on engineering plant immune systems for enhanced pathogen resistance and plant fitness. [ABSTRACT FROM AUTHOR]

During pathogenesis, effector proteins are secreted from the pathogen to the host plant to provide virulence activity for invasion of the host. However, once the host plant recognizes one of the delivered effectors, effector‐triggered immunity activates a robust immune and hypersensitive response (HR). In planta, the effector AvrRps4 is processed into the N‐terminus (AvrRps4N) and the C‐terminus (AvrRps4C). AvrRps4C is sufficient to trigger HR in turnip and activate AtRRS1/AtRPS4‐mediated immunity in Arabidopsis; on the other hand, AvrRps4N induces HR in lettuce. Furthermore, AvrRps4N‐mediated HR requires a conserved arginine at position 112 (R112), which is also important for full‐length AvrRps4 (AvrRps4F) processing. Here, we show that effector processing and effector recognition in lettuce are uncoupled for the AvrRps4 family. In addition, we compared effector recognition by lettuce of AvrRps4 and its homologues, HopK1 and XopO. Interestingly, unlike for AvrRps4 and HopK1, mutation of the conserved R111 in XopO by itself was insufficient to abolish recognition. The combination of amino acid substitutions arginine 111 to leucine with glutamate 114 to lysine abolished the XopO‐mediated HR, suggesting that AvrRps4 family members have distinct structural requirements for perception by lettuce. Together, our results provide an insight into the processing and recognition of AvrRps4 and its homologues. [ABSTRACT FROM AUTHOR]

Background: Bacillus thuringiensis (Bt) has been widely used as a biological control agent for lepidopteran pests. However, resistance to Bt is a major concern associated with Spodoptera spp. (Noctuidae) and Plutella xylostella (Plutellidae). For efficient control of Noctuidae and Plutellidae, novel Bt strains which have high toxicity and a broad host range are needed. Results: To develop novel Bt strains as used for bio‐insecticides, the Bt IMBL‐B9 with high toxicity against Spodoptera exigua, Spodoptera frugiperda and P. xylostella was isolated and characterized. The Bt kurstaki IMBL‐B9 strain produced bipyramidal and cuboidal crystals consisting of cry toxins with molecular weights of 130 and 65 kDa, respectively. This strain harbors eight crystal protein genes in total, including cry1Ea and one vegetative insecticidal protein gene. The median lethal concentration (LC50) values of IMBL‐B9 against S. exigua and S. frugiperda were 21.8‐ and 19.3‐fold lower than those of the Bt kusrstaki strain, and 5.6‐ and 4.9‐fold lower than those of Bt aizawai strain, respectively. To evaluate the insecticidal activity of Cry proteins from IMBL‐B9, cry gene‐sourced recombinant Bt strains were constructed. These strains have insecticidal activity and synergic action against lepidopteran pests. Conclusion: In this study, a novel Bt kurstaki IMBL‐B9 strain was isolated and this could be useful for the development of new bio‐insecticide or cry gene‐based recombinant products as an alternative solution against lepidopterans, including Noctuidae and Plutellidae. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Plants perceive an assortment of external cues during their life cycle, including abiotic and biotic stressors. Biotic stress from a variety of pathogens, including viruses, oomycetes, fungi, and bacteria, is considered to be a substantial factor hindering plant growth and development. To hijack the host cell's defence machinery, plant pathogens have evolved sophisticated attack strategies mediated by numerous effector proteins. Several studies have indicated that plasmodesmata (PD), symplasmic pores that facilitate cell‐to‐cell communication between a cell and neighbouring cells, are one of the targets of pathogen effectors. However, in contrast to plant‐pathogenic viruses, reports of fungal‐ and bacterial‐encoded effectors that localize to and exploit PD are limited. Surprisingly, a recent study of PD‐associated bacterial effectors has shown that a number of bacterial effectors undergo cell‐to‐cell movement via PD. Here we summarize and highlight recent advances in the study of PD‐associated fungal/oomycete/bacterial effectors. We also discuss how pathogen effectors interfere with host defence mechanisms in the context of PD regulation. [ABSTRACT FROM AUTHOR]

Mosquitoes are major pests that attack humans and spread pathogens. To control mosquito larvae, insect growth regulators such as methoprene and pyriproxyfen have been widely used. Juvenile hormone antagonists (JHAN) have the potential to act as an eco‐friendly insecticide with a novel mode of action. Actinomycetes are known as a producer of an enormous number of secondary metabolites. In this study, secondary metabolites of 232 Actinomycetes strains were screened for their juvenile hormone antagonist activity and their mosquito larvicidal activity. Among them, IMBL‐1939, 1952, 2005 and 2064 strains showed mosquito larvicidal activity with JHAN activity. These actinomycetes derived JHAN could be alternative sustainable vector control agents. [ABSTRACT FROM AUTHOR]

Paclitaxel‐coated balloons have demonstrated improved efficacy compared with uncoated percutaneous transluminal angioplasty for femoropopliteal artery disease. While applying a long balloon, twisting of the balloon can be occurred. We reported two cases with twisting of the Ranger drug‐coated balloon for treating superficial femoral artery. [ABSTRACT FROM AUTHOR]

PAL‐XFEL utilizes a three‐chicane bunch compression (3‐BC) scheme (the very first of its kind in operation) for free‐electron laser (FEL) operation. The addition of a third bunch compressor allows for more effective mitigation of coherent synchrotron radiation during bunch compression and an increased flexibility of system configuration. Start‐to‐end simulations of the effects of radiofrequency jitter on the electron beam performance show that using the 3‐BC scheme leads to better performance compared with the two‐chicane bunch compression scheme. Together with the high performance of the linac radiofrequency system, it enables reliable operation of PAL‐XFEL with unprecedented stability in terms of arrival timing, pointing and intensity; an arrival timing jitter of better than 15 fs, a transverse position jitter of smaller than 10% of the photon beam size, and an FEL intensity jitter of smaller than 5% are consistently achieved. [ABSTRACT FROM AUTHOR]

Summary: Unlike animals, plants do not have an adaptive immune system and have instead evolved sophisticated and multi‐layered innate immune mechanisms. To overcome plant immunity, pathogens secrete a diverse array of effectors into the apoplast and virtually all cellular compartments to dampen immune signaling and interfere with plant functions. Here we describe the scope of the arms race throughout the cell and summarize various strategies used by both plants and pathogens. Through studying the ongoing evolutionary battle between plants and key pathogens, we may yet uncover potential ways to achieve the ultimate goal of engineering broad‐spectrum resistant crops without affecting food quality or productivity. [ABSTRACT FROM AUTHOR]

Aim One of the remarkable changes in today's nursing profession is the emergence of male nurses. In order to promote the development of nursing, it would be beneficial for a positive perception of male nurses to be established in society. This study identified the public perceptions of male nurses in South Korea by using Q methodology and offered basic strategies for enhancing the perception of male nurses. Methods A Q-methodological approach, suitable for subjective research, was used for a survey. Q statements were based on 600 Q concourses that were collected through a literature review and individual interviews. Thirty-seven final Q statements were selected from those. The P sample was collected from 45 persons who were likely to represent a diverse range of views about male nurses. The collected data were analyzed with PQMethod software; a principal component factor analysis with varimax rotation was used to identify the patterns of the public's perception of male nurses. Results Four distinct perspectives were identified: progressive occupational; conservative occupational; negative occupational; and supportive occupational. Conclusion This study provided strategies for improving the public's views of male nurses in a conservative country with gender stereotypes. These findings also could attract more male nurses into the profession and increase their retention. [ABSTRACT FROM AUTHOR]

Purpose Researchers recently suggested intravenous paracetamol as a potential cause of hypotension. We aimed to investigate risk factors of paracetamol- and propacetamol-associated adverse drug reactions (ADRs) in Korean individuals. Methods All adverse hypotension cases, regardless of suspected drug, and all ADRs associated with paracetamol and propacetamol use were collected from the Korea Adverse Event Reporting System database between 2011 and 2014. The seriousness, causality, and type of ADR were classified. Results Of 4,771 cases of adverse hypotension, 403 (8.4%) were reported to be related to propacetamol. This was comparable to the rate of hypotension associated with fentanyl (454, 9.5%), the major suspected drug of hypotension. Paracetamol-associated hypotension accounted for merely 1.2% (55 cases) of all hypotension cases. Among ADRs associated with propacetamol use, hypotension was the most common (37.1%), whereas cutaneous reactions were the primary paracetamol-associated ADR. Propacetamol/paracetamol-associated hypotension was frequently recorded in older patients (≥54 years) (53.9 ± 25.8 vs. 42.8 ± 21.7, P < 0.001) and taking more concomitant drugs (1.9 ± 5.0 vs. 1.1 ± 3.2, P < 0.001). Also, compared with other ADRs associated by propacetamol/paracetamol, hypotension was more commonly assessed as a serious outcome (27.3% vs. 11.4%, P < 0.001). Regarding concomitant medications, the risk for hypotension associated with propacetamol was significantly increased in patients simultaneously taking antibacterials (J01), cold preparations (R05), drugs for acid related disorders (A02), blood substitutes (B05), or antithrombotics (B01). Conclusions Propacetamol was found to be a major suspected drug of pharmacologically associated hypotension in Korea. Older and male patients taking medications in combination with propacetamol/paracetamol should undergo monitoring of their blood pressure. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Transposable elements ( TEs) and repetitive sequences are ubiquitously present in eukaryotic genomes which are in general epigenetically silenced by DNA methylation and/or histone 3 lysine 9 methylation (H3K9me). RNA-directed DNA methylation (Rd DM) is the major pathway that initiates de novo DNA methylation in Arabidopsis and sets up a self-reinforcing silencing loop between DNA methylation and H3K9me. However, a key issue is the requirement of a basal level transcript from the target loci to initiate the RNA-based silencing. How the heterochromatic silenced loci are transcribed remains largely unknown. Here, we show that JMJ24, a JmjC domain-containing protein counteracts H3K9me to promote basal level transcription of endogenous silenced loci in Arabidopsis. JMJ24 functionally resembles the fission yeast JmjC protein Epe1. The transcript promoted by JMJ24 is, at least in part, processed to small RNA to initiate the Rd DM. Genome-wide transcriptome profiling indicates that transcript levels of TEs are more likely regulated by JMJ24, compared with protein-coding genes. Our data suggest that JMJ24 plays a conserved role in promoting basal level transcription of endogenous silenced loci to reinforce the silencing. We also provide evidence of a physical association between JMJ24 and RNA-dependent RNA polymerase 2 ( RDR2), which represents an evolved property of the RNA silencing pathway. [ABSTRACT FROM AUTHOR]

One's ability to properly regulate emotion is critical to psychological and physical well-being. Among various strategies to regulate emotion, cognitive reappraisal has been shown to modulate both emotional experience and emotional memory. However, most studies of reappraisal have focused on reappraisal of negative situations, with reappraisal of positive emotion receiving considerably less attention. In addition, the effects of reappraisal on emotional reactions to stimuli are typically only assessed either immediately or after a short delay, and it remains unclear whether reappraisal effects persist over longer time periods. We investigated the effect of cognitive reappraisal on emotional reactions and long-term episodic memory for positive and negative stimuli. Men and women viewed emotionally negative, positive, and neutral pictures while they were instructed to either increase, decrease, or maintain the initial emotional reactions elicited by the pictures. Subjective ratings of emotional valence and arousal were assessed during the regulation task and again after 1 week. Memory for the pictures was assessed with free recall. Results indicated that pictures accompanied by instructions to increase emotion were better recalled than pictures reappraised to decrease emotion. Modulation of emotional arousal elicited by stimuli persisted over a week, but this effect was observed only for men. These findings suggest that cognitive reappraisal can have long-lasting effects on emotional reactions to stimuli. However, the sex differences observed for the effects of reappraisal on emotional reactions highlight the importance of considering individual differences in the effects of regulation. [ABSTRACT FROM AUTHOR]

The plant immune system must be tightly controlled both positively and negatively to maintain normal plant growth and health. We previously identified SUPPRESSOR OF rps4- RLD1 ( SRFR1) as a negative regulator specifically of effector-triggered immunity. SRFR1 is localized in both a cytoplasmic microsomal compartment and in the nucleus. Its TPR domain has sequence similarity to TPR domains of transcriptional repressors in other organisms, suggesting that SRFR1 may negatively regulate effector-triggered immunity via transcriptional control. We show here that excluding SRFR1 from the nucleus prevented complementation of the srfr1 phenotype. To identify transcription factors that interact with SRFR1, we screened an Arabidopsis transcription factor prey library by yeast two-hybrid assay and isolated six class I members of the TEOSINTE BRANCHED1/ CYCLOIDEA/ PCF ( TCP) transcription factor family. Specific interactions were verified in planta. Although single or double T- DNA mutant tcp8, tcp14 or tcp15 lines were not more susceptible to bacteria expressing AvrRps4, the triple tcp8 tcp14 tcp15 mutant displayed decreased effector-triggered immunity mediated by the resistance genes RPS2, RPS4, RPS6 and RPM1. In addition, expression of PATHOGENESIS- RELATED PROTEIN2 was attenuated in srfr1- 4 tcp8- 1 tcp14- 5 tcp15- 3 plants compared to srfr1- 4 plants. To date, TCP transcription factors have been implicated mostly in developmental processes. Our data indicate that one function of a subset of TCP proteins is to regulate defense gene expression in antagonism to SRFR1, and suggest a mechanism for an intimate connection between plant development and immunity. [ABSTRACT FROM AUTHOR]

Dorsoventral patterning of the Drosophila ventral neuroectoderm is established by the expression of three evolutionarily conserved homeodomain genes: ventral nervous system defective ( vnd), intermediate neuroblasts defective ( ind), and muscle segment homeobox ( msh) in the medial, intermediate, and lateral columns of the ventral neuroectoderm, respectively. It was not clear whether extrinsic factor(s) from the CNS midline cells influence the initial dorsoventral patterning by controlling the expression of the dorsoventral patterning genes. We show here that the CNS midline cells, specified by single-minded ( sim), are essential for maintaining expression of the dorsoventral patterning genes. Ectopic expression of sim in the ventral neuroectoderm during the blastoderm stage repressed expression of the three homeodomain genes in the ventral neuroectoderm. This indicates that the identity of the CNS midline cells is established by a series of repressions of the three homeodomain genes in the ventral neuroectoderm. Ectopic expression of sim in the ventral neuroectoderm during initial neurogenesis induced ectopic ind expression in the medial column in addition to that in the intermediate column via EGFR signaling between the ventral neuroectoderm and midline cells. In contrast, it repressed the expression of vnd and msh in the medial and lateral columns, respectively. Our findings demonstrate that the CNS midline cells provide extrinsic positional information via EGFR signaling that maintains the initial subdivision of the ventral neuroectoderm into three dorsoventral columns during initial neurogenesis. © 2004 Wiley Periodicals, Inc. J Neurobiol, 2005 [ABSTRACT FROM AUTHOR]

In this paper, an RF curve-fitting predistorter is proposed to extend the linearized dynamic range of a power amplifier. AM-AM and AM-PM distortion of the power amplifier can be compensated by accurately adjusting the gain and phase gradients of the three-reflection-type diode predistorter. The proposed predistorter extends the linearized dynamic range by more than six times that of a conventional predistorter. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 83–87, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11292 [ABSTRACT FROM AUTHOR]

An important step in Drosophila neurogenesis is to establish the neural dorsoventral (DV) patterning. Here we describe how dpp loss-of- and gain-of-function mutation affects the homeobox-containing neural DV patterning genes expressed in the ventral neuroectoderm. Ventral nervous system defective (vnd), intermediate neuroblast defective (ind), muscle-specific homeobox (msh), and orthodenticle (otd) genes participate in development of the central nervous system and peripheral nervous system, and encode homeodomain proteins. otd and msh genes were ectopically expressed in dpp loss-of-function mutation, but vnd and ind were not affected. However, when dpp was ectopically expressed in the ventral neuroectoderm by rho-GAL4/UAS-dpp system, it caused the repression of vnd, and msh expressions in ventral and dorsal columns of the neuroectoderm, respectively, but not that of ind. The later expression pattern of otd was also restricted by Dpp. The expression pattern of msh, vnd and otd in dpp loss-of-function and gain-of-function mutation indicates that Dpp activity does not reach to the ventral midline and it works locally to establish the dorsal boundary of the ventral neuroectoderm. [Copyright &y& Elsevier]

Presents information on a study which looked at the retaining of red beet color by repeated regeneration of fresh beet juice pigments with the help of food additives like ascrobic acid, isoascorbic acid, gallic acid, gluconic acid, and others. Description of some methods that have been used to stop loss or improve the stability of pigments; Indepth look at the termal destruction and regeneration of red beet juice pigments.