Preface: Special issue: 14th International Conference on Brain Energy Metabolism: Energy substrates and microbiome govern brain bioenergetics and cognitive function with aging.

This Preface introduces the Special Issue entitled, "Energy Substrates and Microbiome Govern Brain Bioenergetics and Cognitive Function with Aging", which is comprised of manuscripts contributed by invited speakers and program/organizing committee members who participated in the 14th International Conference on Brain Energy Metabolism (ICBEM) held on October 24-27, 2022 in Santa Fe, New Mexico, USA. The conference covered the latest developments in research related to neuronal energetics, emerging roles for glycogen in higher brain functions, the impact of dietary intervention on aging, memory, and Alzheimer's disease, roles of the microbiome in gut-brain signaling, astrocyte-neuron interactions related to cognition and memory, novel roles for mitochondria and their metabolites, and metabolic neuroimaging in aging and neurodegeneration. The special issue contains 25 manuscripts on these topics plus three tributes to outstanding scientists who have made important contributions to brain energy metabolism and participated in numerous ICBEM conferences. In addition, two of the manuscripts describe important directions and the rationale for future research in many thematic areas covered by the conference.

Increases in anterograde axoplasmic transport in neurons of the hyper-glutamatergic, glutamate dehydrogenase 1 (Glud1) transgenic mouse: Effects of glutamate receptors on transport.

The excitatory neurotransmitter glutamate has a role in neuronal migration and process elongation in the central nervous system (CNS). The effects of chronic glutamate hyperactivity on vesicular and protein transport within CNS neurons, that is, processes necessary for neurite growth, have not been examined previously. In this study, we measured the effects of lifelong hyperactivity of glutamate neurotransmission on axoplasmic transport in CNS neurons. We compared wild-type (wt) to transgenic (Tg) mice over-expressing the glutamate dehydrogenase gene Glud1 in CNS neurons and exhibiting increases in glutamate transmitter formation, release, and synaptic activation in brain throughout the lifespan. We found that Glud1 Tg as compared with wt mice exhibited increases in the rate of anterograde axoplasmic transport in neurons of the hippocampus measured in brain slices ex vivo, and in olfactory neurons measured in vivo. We also showed that the in vitro pharmacologic activation of glutamate synapses in wt mice led to moderate increases in axoplasmic transport, while exposure to selective inhibitors of ion channel forming glutamate receptors very significantly suppressed anterograde transport, suggesting a link between synaptic glutamate receptor activation and axoplasmic transport. Finally, axoplasmic transport in olfactory neurons of Tg mice in vivo was partially inhibited following 14-day intake of ethanol, a known suppressor of axoplasmic transport and of glutamate neurotransmission. The same was true for transport in hippocampal neurons in slices from Glud1 Tg mice exposed to ethanol for 2 h ex vivo. In conclusion, endogenous activity at glutamate synapses regulates and glutamate synaptic hyperactivity increases intraneuronal transport rates in CNS neurons.

Sphingomonas Immobilis sp. nov., and Sphingomonas natans sp. nov. bacteria isolated from soil.

Two novel strains of bacteria, CA1-15T and BIUV-7T, were isolated from soil samples gathered in Cheonan-si, Republic of Korea, and Inje-gun, Republic of Korea, respectively. These bacteria are Gram-negative, aerobic, and non-motile. Phylogenetic evaluations, using the sequence of the 16S rRNA gene, showed that strains CA1-15T and BIUV-7T belong to a distinctive clade within the family Sphingomonadaceae (order Sphingomonadales, class Alphaproteobacteria). The strains exhibited the highest similarity in their genetic makeup with representatives of the genus Sphingomonas. Strain CA1-15T was closely related to Sphingomonas echinoides NRRL B-3126T (97.8% similarity in 16S rRNA gene sequence), Sphingomonas oligophenolica JCM 12,082T (97.8%), Sphingomonas glacialis C16yT (97.6%) and Sphingomonas psychrolutea MDB1-AT (97.3%). Strain BIUV-7T was closely related to Sphingomonas nostoxanthinifaciens AK-PDB1-5T (97.0%), Sphingomonas vulcanisoli SN6-13T (96.3%), Sphingomonas naphthae DKC-5-1T (96.2%), and Sphingomonas prati W18RDT (95.7%). The optimal growth conditions for strains CA1-15T and BIUV-7T were determined to be at pH 7.0 and a temperature of 25 °C. Analysis of the cellular fatty acids of strain CA1-15T and BIUV-7T revealed that summed feature 8 (C18:1ω7c/C18:1ω6c) (60.4%), summed feature 8 (C18:1ω7c/C18:1ω6c) (62.9%) were the major component, respectively. Additionally, both strains exhibited ubiquinone Q-10 as their major respiratory quinone, and diphosphatidylglycerol (DPG), glycosphingolipid (SGL), and phosphatidylethanolamine (PE) as the major polar lipid. The genome of strain CA1-15T measures 4,133,944 bp, comprising 4,026 coding sequences (CDSs) and 46 tRNA genes. Similarly, the genome of strain BIUV-7T is 4,563,252 bp, characterized by 4,226 CDSs and 44 tRNA genes. The average nucleotide identity (ANI) analysis and digital DNA-DNA hybridization (dDDH) values between strain CA1-15T and other Sphingomonas species range from 73.2 to 79.9% and 19.4-22.9%, respectively. Comparatively, ANI and dDDH values between strain BIUV-7T and other Sphingomonas species are in the range of 72.9-76.5% and 19.3-20.9%, respectively. Based on the biochemical, chemotaxonomic, and phylogenetic analyses, it is evident that strains CA1-15T and BIUV-7T represent two novel bacterial species within the genus Sphingomonas. Accordingly, the names Sphingomonas immobilis sp. nov. and Sphingomonas natans sp. nov. are proposed. also, CA1-15T(= KCTC 92960T = NBRC 116547T) is the type strain of Sphingomonas immobilis and BIUV-7T(= KCTC 92961T = NBRC 116546T) is the type strain of Sphingomonas natans.

A tribute to Sebastián Cerdán and his key contributions to brain metabolism.

This is a tribute to Sebastián Cerdán, a brilliant and innovative NMR spectroscopist whose studies contributed greatly to the fundamental information to the understanding of brain metabolism, particularly in regard to multinuclear magnetic resonance spectroscopy (MRS) techniques. Sebastián Cerdán sadly passed away in May 2022. He was a wonderful mentor and colleague who will be greatly missed.

Non-invasive in vivo measurements of metabolic alterations in the type 2 diabetic brain by 1 H magnetic resonance spectroscopy.

Type 2 diabetes (T2D) is a complex chronic metabolic disorder characterized by hyperglycemia because of insulin resistance. Diabetes with chronic hyperglycemia may alter brain metabolism, including brain glucose and neurotransmitter levels; however, detailed, longitudinal studies of metabolic alterations in T2D are lacking. To shed insight, here, we characterized the consequences of poorly controlled hyperglycemia on neurochemical profiles that reflect metabolic alterations of the brain in both humans and animal models of T2D. Using in vivo 1 H magnetic resonance spectroscopy, we quantified 12 metabolites cross-sectionally in T2D patients and 20 metabolites longitudinally in T2D db/db mice versus db+ controls. We found significantly elevated brain glucose (91%, p < 0.001), taurine (22%, p = 0.02), glucose+taurine (56%, p < 0.001), myo-inositol (12%, p = 0.02), and choline-containing compounds (10%, p = 0.01) in T2D patients versus age- and sex-matched controls, findings consistent with measures in T2D db/db versus control db+ littermates. In mice, hippocampal and striatal neurochemical alterations in brain glucose, ascorbate, creatine, phosphocreatine, γ-aminobutyric acid, glutamate, glutamine, glutathione, glycerophosphoryl-choline, lactate, myo-inositol, and taurine persisted in db/db mice with chronic disease progression from 16 to 48 weeks of age, which were distinct from control db+ mice. Overall, our study demonstrates the utility of 1 H magnetic resonance spectroscopy as a non-invasive tool for characterizing and monitoring brain metabolic changes with T2D progression.

Characteristics and Potential Challenges of Digital-Based Interventions for Children and Young People: Scoping Review.

BACKGROUND: Digital health technologies are becoming increasingly available to children and young people and their families. However, there are no scoping reviews that provide both an overview of the characteristics of digital interventions for children and young people and potential challenges to be considered when developing and implementing them. OBJECTIVE: This study aimed to systematically review scientific publications to identify the current characteristics and potential complications of digital interventions for children and young people. METHODS: This scoping review was conducted using the framework of Arksey and O'Malley and adheres to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines for scoping reviews. A search of 5 databases (PubMed, Scopus, Embase, MEDLINE, and CINAHL) and Google Scholar was performed for eligible clinical trials published between January 1, 2018, and August 19, 2022. RESULTS: The initial search of the 5 databases yielded 3775 citations; duplicates and those not meeting the inclusion criteria were eliminated. In total, 34 articles were included in the final review and relevant information, such as the descriptive characteristics and potential challenges, were classified. Mental health (26/34, 76%) was the most common target for the digital intervention for children and young people, exceeding physical health (8/34, 24%) by more than 3 times. In addition, a substantial number of digital interventions were dedicated solely to children and young people. Digital interventions for children and young people were more likely to be delivered via computers (17/34, 50%) rather than smartphones (13/34, 38%). More than one-third of the studies (13/34, 38%) applied cognitive behavioral theory as the theory of digital interventions. The duration of the digital intervention for children and young people was more likely to vary depending on the target user rather than the target disease. Intervention components were classified into 5 categories: guidance, task and activity, reminder and monitoring, supportive feedback, and reward system. Potential challenges were subcategorized into ethical, interpersonal, and societal challenges. For ethical challenges, the consent of children and young people or caregivers, potential risk of adverse events, and data privacy issues were considered. For interpersonal challenges, the engagement of children and young people was affected by the preference or barrier of caregivers to participate in studies. For societal challenges, restricted ethnicity in recruitment, limited availability of digital technology, differences in internet use patterns between girls and boys, unified clinical settings, and language barriers were described. CONCLUSIONS: We identified potential challenges and provided suggestions about ethical, interpersonal, and societal aspects to consider when developing and deploying digital-based interventions for children and young people. Our findings provide a thorough overview of the published literature and may serve as a comprehensive, informative foundation for the development and implementation of digital-based interventions for children and young people.

First Report of Powdery Mildew Caused by Golovinomyces ambrosiae on Xanthium orientale in Korea.

Xanthium orientale L. (syn. Xanthium canadense Mill., Asteraceae), known as cocklebur, is an annual weed native to North America, which is now a neophyte distributed throughout the world. This plant was accidentally introduced to Korea in the late 1970s ( So et al. 2008) and is considered a problematic exotic weed in orchards, for which many herbicides are ineffective (Kim et al. 2020). In September 2018, powdery mildew was observed on X. orientale in Jeju, Korea. The disease incidence ranged from 40 to 60%. Voucher specimens were deposited in the Korea University Herbarium (Accession No. KUS-F30795) and Kunsan National University Herbarium (KSNUH1988). Symptoms appeared as round to irregular white patches with abundant hyphal growth on the leaf surface. Hyphal appressoria were nipple-shaped, and 3 to 6 µm diam. Conidiophores (n = 30) were 145 to 206 × 9 to 11.6 µm and produced 2 to 5 immature conidia in chains with a sinuate outline. Foot-cells of the conidiophores were straight, cylindrical, and 43 to 100.9 µm long. Conidia (n = 30) were ellipsoid-ovoid, doliiform to somewhat limoniform, 25.2 to 31.8 × 13.6 to 16.8 µm (l/w 1.6 to 2.1), and devoid of distinct fibrosin bodies. The morphological characteristics corresponded to those of Golovinomyces ambrosiae (Schwein.) U. Braun & R.T.A. Cook (Braun and Cook 2012, under Golovinomyces spadiceus (Beck. & M.A. Curtis) U. Braun; Qiu et al. 2020). To confirm the identity of the causal fungus, the internal transcribed spacer (ITS), large subunit (LSU) (Bradshaw and Tobin 2020), the intergenic spacer (IGS) of rDNA, and the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene (Bradshaw et al. 2022) were amplified for a herbarium specimen (KUS-F30795). A BLASTn search of these sequences revealed 100% identity with reference sequences of G. ambrosiae on diverse Asteraceae plants (AB077644 for ITS, AB077643 for LSU, ON361171 for IGS, and ON075648 for GAPDH). However, there was a single nucleotide difference on both the IGS and GAPDH sequences when compared to the closely related species Golovinomyces latisporus. The sequences were deposited in GenBank (Accession No. OQ165157 (ITS), OQ165164 (LSU), OR050524 (IGS), and OR086076 (GAPDH)). Phylogenetic analyses of ITS, LSU, IGS, and GAPDH sequences revealed the Korean sample formed a well-supported group with other G. ambrosiae sequences, confirming its identity. A pathogenicity test was performed through inoculation by gently pressing diseased leaves onto the leaves of five healthy plants. Five non-inoculated plants served as controls. All plants were maintained in a greenhouse at 25±2°C. Powdery mildew colonies developed on the inoculated plants after ten days, whereas the control plants remained symptomless. The fungus present on the inoculated leaves was morphologically identical to that observed on the initially diseased leaves, fulfilling Koch's postulates. Powdery mildew on X. orientale has previously been reported as Golovinomyces cichoracearum (≡ Erysiphe cichoracearum) sensu lato in the USA, G. ambrosiae (= G. spadiceus) throughout all continents, and Podosphaera fusca sensu lato (now P. xanthii) in Korea (Braun and Cook 2012; Farr and Rossman 2023). To date, powdery mildew in Korea has been reported only on Xanthium strumarium as G. cichoracearum s. lat. and Podosphaera xanthii (KSPP 2022). To our knowledge, this is the first report of powdery mildew caused by G. ambrosiae on X. orientale in Korea.

First Report of Powdery Mildew Caused by Podosphaera xanthii on Verbena bonariensis in Korea.

Verbena bonariensis L. (Verbenaceae), known as purple-top vervain or Argentinian vervain, is a perennial, herbaceous plant, native to tropical South America. It is widely grown as an ornamental worldwide. During summer and autumn of 2022, V. bonariensis of an unknown cultivar with purple-violet flowers was found infected by powdery mildew fungus with 100% disease incidence in a public garden in Jeonju, Korea. White, superficial mycelia developed on infected plants and subsequently covered whole surfaces of leaves and stems, resulting in leaf discoloration and early defoliation. High disease severity caused poor growth of the plants, resulting in premature senescence and reduced flowering. A representative voucher specimen was submitted in the Korea University herbarium (KUS-F33160). Morphological characterization and measurements of the fungus were carried out using a fresh sample. Appressoria on the mycelium were poorly developed, nipple-shaped or nearly absent. Conidiophores were 90 to 246 × 10 to 12 µm and produced 2 to 7 immature conidia in chains with a crenate outline. Foot-cells of conidiophores were straight, cylindrical, relatively short, 42 to 64 µm long, and constricted at the branching point from the hypha. Conidia were hyaline, ellipsoid to ovate, measured 28 to 40 × 18 to 22 µm (length/width ratio of 1.4 to 2.0), and contained conspicuous fibrosin bodies. Germ tubes were produced from the lateral position of conidia. No chasmothecia were observed throughout the growingseason. These diagnostic structures were typical to the anamorph of the genus Podosphaera. The morphological characteristics and measurements were consistent with those of P. xanthii (Castagne) U. Braun & Shishkoff (Braun & Cook 2012). To confirm morphology-based identification, the nucleotide sequences of the internal transcribed specer region (ITS1 and ITS2) and large subunit gene (LSU) of the rDNA were determined in this study outlined by Bradshaw and Tobin (2020). The resulting sequences were submitted to GenBank (OQ061318 for ITS, OQ061319 for LSU) and were 100% identical with sequences of Podosphaera xanthii (MT242593, LC371331 etc.) for both ITS and LSU gene from the BLAST'n search results. Thus, based on morphology and results of molecular analysis, the isolate on V. bonariensis in Korea was identified as P. xanthii. The pathogenicity test was carried out by touching a diseased leaf onto healthy leaves of five pot-grown plants. Five non-inoculated plants were used as controls. After 7 days, typical powdery mildew colonies started to appear on the inoculated leaves. All control plants remained symptomless. The fungus isolated from the inoculated leaves was morphologically identical to that observed on the originally diseased leaves, which supports Koch's postulates. Hitherto, powdery mildew of Verbena spp. associated with Podosphaera sp. (including Sphaerotheca sp.) has been globally reported (Farr & Rossman 2022). Podosphaera xanthii on V. bonariensis was recorded from China and Japan (Hong et al. 2021, Farr & Rossman 2022), while in Korea, this fungus was recorded on Verbena brasiliensis (Cho et al. 2014), but not on V. bonariensis. To our knowledge, this is the first report of powdery mildew disease caused by P. xanthii on V. bonariensis in Korea. Our field observations suggest that this powdery mildew occurs on V. bonariensis planted in the shade. This finding could be useful for the breeding programme of Verbena spp. and for planting strategies in gardens.

Normalization of Cerebral Blood Flow, Neurochemicals, and White Matter Integrity after Kidney Transplantation.

BACKGROUND: CKD is associated with abnormalities in cerebral blood flow, cerebral neurochemical concentrations, and white matter integrity. Each of these is associated with adverse clinical consequences in the non-CKD population, which may explain the high prevalence of dementia and stroke in ESKD. Because cognition improves after kidney transplantation, comparing these brain abnormalities before and after kidney transplantation may identify potential reversibility in ESKD-associated brain abnormalities. METHODS: In this study of patients with ESKD and age-matched healthy controls, we used arterial spin labeling to assess the effects of kidney transplantation on cerebral blood flow and magnetic resonance spectroscopic imaging to measure cerebral neurochemical concentrations (N-acetylaspartate, choline, glutamate, glutamine, myo-inositol, and total creatine). We also assessed white matter integrity measured by fractional anisotropy (FA) and mean diffusivity (MD) with diffusion tensor imaging. We used a linear mixed model analysis to compare longitudinal, repeated brain magnetic resonance imaging measurements before, 3 months after, and 12 months after transplantation and compared these findings with those of healthy controls. RESULTS: Study participants included 29 patients with ESKD and 19 controls; 22 patients completed post-transplant magnetic resonance imaging. Cerebral blood flow, which was higher in patients pretransplant compared with controls (P=0.003), decreased post-transplant (P<0.001) to values in controls. Concentrations of neurochemicals choline and myo-inositol that were higher pretransplant compared with controls (P=0.001 and P<0.001, respectively) also normalized post-transplant (P<0.001 and P<0.001, respectively). FA increased (P=0.001) and MD decreased (P<0.001) post-transplant. CONCLUSIONS: Certain brain abnormalities in CKD are reversible and normalize with kidney transplantation. Further studies are needed to understand the mechanisms underlying these brain abnormalities and to explore interventions to mitigate them even in patients who cannot be transplanted. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: Cognitive Impairment and Imaging Correlates in End Stage Renal Disease, NCT01883349.

First Report of Leaf Spot Caused by Septoria erigerontis on Conyza sumatrensis in Korea.

Conyza sumatrensis (Retz.) E. Walker (syn. Erigeron sumatrensis) or commonly known as fleabane, is an annual herbaceous plant native to South America. It/span>was accidentally introduced to Korea in the 1930s and became invasive in natural and managed ecosystems of the country (Kim et al. 2008). Leaf spots on this plant were first observed in March 2013 in Jeju (33°29'45"N; 126°26'26"E), and then in February 2017 in Seoguipo (33°14'30"N; 126°32'58"E), Korea. The severity of the disease was estimated to be greater than 50%. Initial symptoms were small, distinct, reddish-brown, then turned into brown spots with dark purplish-brown margins. Conidiomata were pycnidial, epigenous, occasionally hypogenous, scattered, dark brown to rusty brown, globose, embedded in host tissue or partly erumpent, 70 to 165 µm in diameter, with ostioles measuring 10 to 26 µm in diameter. Conidia were straight to flexuous, 24 to 65 × 1.5 to 2.0 µm, hyaline, and 1 to 5 septate. Morphological circumscriptions were consistent with Septoria erigerontis Peck (Verkley et al. 2013). To obtain a monoconidial isolate, conidia were collected from lesions, placed in an Eppendorf tube containing sterile water and streaked onto the surface of 2% water agar (WA) plates supplemented with 100 mg/L of streptomycin sulfate, and after five days transferred onto potato dextrose agar (PDA). The two-week-old colonies incubated at 25°C on PDA had a slightly ruffled, but mostly colorless margin; colonies were 5 to 7 mm in diameter, slightly elevated in the center, surface black, covered with a diffuse to a dense mat of grey aerial mycelium. Voucher specimens were housed in the Korea University Herbarium (KUS-F27274 and F29725), and two cultures were deposited in the Korea Agricultural Culture Collection (Accession Nos: KACC47219 and KACC48297). Nucleotide sequences of the internal transcribed spacer (ITS), translation elongation factor 1-α (EF), actin (ACT), 28S rDNA (LSU), and RNA polymerase II second largest subunit (RPB2) genes obtained from KACC47219 were determined (Verkley et al. 2013) and deposited in GenBank (Accession Nos: OM909018, OM908934, OM974318, OM974319, OM974320). Results of BLASTn search for ITS and LSU were 99-100% identical with reference sequences of Septoria erigerontis (MH865036, MH876473), S. lactucae (MK617321), and S. phlogis (MH876550) in GenBank. Whereas it showed 97% similarity for ACT, 93-94% for EF and RPB2 genes with sequences of S. erigerontis (JQ325031, KF253363, KF252411). Pathogenicity was tested by spraying 20 leaves of four-month-old three potted plants with a conidial suspension (1×104 propagules/mL) harvested from a four-week-old culture (span style="font-family:'Times New Roman'">KACC47219). Ten leaves were used as controls. The plants were placed in a dew chamber at 26°C for 24 h, then moved to a greenhouse. Inoculated leaves developed typical symptoms after seven days, whilst no symptoms were observed on control ones. S. erigerontis was re-isolated from symptomatic lesion and its identity was confirmed by microscopic studies, fulfilling Koch's postulates. Although S. erigerontis has been recorded to be associated with leaf spots of Erigeron spp. and Conyza spp. (Farr and Rossman 2022), there is no previous record of this fungus on C. sumatrensis. To our knowledge, this is the first report of leaf spot caused by S. erigerontis on C. sumatrensis worldwide as well as in Korea. We presume that this fungus may have potential as a biocontrol agent on fleabanes, particularly glyphosate-resistant Conyza species (Sansom et al. 2013). References: Farr, D. F., and Rossman, A. Y. Fungal Databases, Syst. Mycol. Microbiol. Lab., Online publication. ARS, USDA. Accessed 6 February 2022. Kim, C. S., et al. 2008. Korean J. Weed Sci. 28:42. Sansom, M., et al. 2013. Plant Protect. Sci. 49:44. Verkley, G. J. M., et al. 2013. Stud. Mycol. 75:213.

First Report of Powdery Mildew Caused by Podosphaera xanthii on Cucurbita ficifolia in Korea.

Cucurbita ficifolia Bouché, called fig-leaf gourd, is a cucurbitaceous climbing plant native to the Americas. During summer and autumn of 2020, almost all of fig-leaf gourds planted in an experimental plot in Jeonju (35°50'54″N, 127°07'46″E), Korea, were found to be infected by a powdery mildew with a 100% disease severity. Symptoms first appeared as white, small, irregular colonies, later coalesced into abundant hyphal growth on both sides of the leaves and young stems. Subsequently premature senescence and poor growth of affected leaves was observed. A voucher specimen was housed in the Korea University herbarium (KUS-F32173). For morphological characterization of the fungus, fresh materials were used for microscopy. Conidiophores (n = 30) were straight, 90 to 190 × 10 to 12 µm and produced three to six immature conidia in chains with a crenate outline. Conidia (n = 30) were ellipsoid-ovoid to barrel-shaped, measured 28 to 38 × 18 to 24 µm with a length/width ratio of 1.3 to 2.0, and contained distinct fibrosin bodies. No chasmothecia were found over the course of the season. The morphological feature of the fungus and the host genus were compatible with those of Podosphaera xanthii (Castagne) U. Braun & Shishkoff (Braun and Cook 2012), a well-known cucurbitaceous powdery mildew. For further confirmation, DNA was extracted from mycelium taken from above mentioned specimen. Internal transcribed spacers (ITS1 and ITS2) and large subunit (LSU) gene of the rDNA were amplified using primer pairs ITS1F/PM6 and PM3/TW14, respectively (Takamatsu and Kano 2001). Newly obtained sequences were registered to the GenBank under the accession numbers OL677355 for ITS and OL677356 for LSU. Our sequences shared 99.54~99.77% identity for ITS (MW559231 and MT250855) and 99.58% for LSU with sequences of P. xanthii (MK357445 and MK357438) in BLAST'n search. Pathogenicity tests were performed twice by pressing method of mycelial patches of the infected leaf onto the young leaves of five healthy fig-leaf gourd plants. Five non-inoculated plants were used as controls. Inoculated leaves started to develop powdery mildew signs after 5 days treatment, whereas the control plants remained symptomless. The fungus on the inoculated plants was morphologically identical to that originally observed on diseased plants, fulfilling Koch's postulates. To date three powdery mildew species have been reported on C. ficifolia (Farr and Rossman 2021). Among these reports, Golovinomyces orontii sensu lato was known from Chile, Mexico, United Kingdom, and Germany, Leveillula taurica from Korea and Podosphaera fuliginea (currently P. xanthii) was recorded Australia and India. To our knowledge, this is the first report of P. xanthii on C. ficifolia in Korea. Since this plant is used as grafting rootstock for preventing soil-borne gummy stem blight of cucumber caused by Didymella bryoniae in Korea (Choi et al. 2009), economic importance of the powdery mildew occurring on leaves of this plant is currently limited. Nevertheless, presence of a powdery mildew could be informative to breeding program of Cucurbita spp. and safe production of C. ficifolia fruits globally.

First Report of Powdery Mildew Caused by Golovinomyces ambrosiae on Leucanthemum vulgare in Korea.

Leucanthemum vulgare Lam. (Asteraceae), known as ox-eye daisy, is a perennial herb native to Europe and western Asia (Clements et al. 2004, McDougall et al. 2018). In Korea, this plant was introduced for ornamental purposes but has been naturalized as a widespread invasive species. In June 2015, symptoms of a powdery mildew disease were observed on L. vulgare in a public garden in Goseong (38°14'18"N, 128°32'56"E), Korea. Since then, its findings have continued throughout the country, including Mokpo and Seogwipo (in 2018), Hongcheon and Seoul (in 2020), Boeun, Gunsan, and Namwon (in 2022), where the disease incidence was often higher than 80%. Symptoms first appeared as circular to irregular white powdery patches covering leaves and stems. Affected plants became distorted, eventually losing their aesthetic and ornamental value. A total of sixteen samples were deposited in the herbarium of Korea University (KUS-F), Korea. Microscopic observations showed that hyphal appressoria were nipple-shaped. Conidiophores were cylindrical, 98 to 157 × 9 to 12 µm, and produced 2 to 5 immature conidia in chains with a sinuate outline. Foot cells were cylindrical, straight, and 37 to 65 µm long. Conidia were ellipsoid to barrel-shaped, 23 to 39 × 12 to 19 µm, with a length/width ratio of 1.4 to 2.3 and devoid of fibrosin bodies. Germ tubes were produced in the perihilar position of the conidia. Primary conidia were apically rounded and basally subtruncated. No chasmothecia were found until the plants died in winter. The morphological characteristics were typical for anamorph of the genus Golovinomyces. To identify the fungus, genomic DNA was extracted from the four herbarium specimens (KUS-F 28650, 30839, 31728, and 31787). PCR products were amplified using the primer sets PM10/ITS4 for internal transcribed spacer (ITS) and PM3/TW14 for the large subunit (LSU) of the rDNA (Mori et al. 2000, Bradshaw and Tobin 2020). Sequences obtained in the present study were deposited at GenBank (accession numbers ON834488-91 for ITS and ON834494-7 for LSU). A BLASTn search of the Korean specimens showed 100% identity with reference sequences of G. ambrosiae in GenBank (KX98730, MK452580, and MK452588 for ITS and MF612182, MK452653, and MK452661 for LSU). In phylogenetic trees of a concatenated dataset of the ITS and LSU sequences, the Korean specimens formed a well-supported clade with the reference sequences of G. ambrosiae. Pathogenicity tests were carried out by touching and dusting an infected leaf (KUS-F 31787) onto the upper leaf surface of five healthy plants. Five non-inoculated plants served as controls. After two weeks, all inoculated plants formed white patches on the surface of leaves and stems, whereas the control plants remained symptomless. The fungus on the inoculated plants was identical to that observed on the initially diseased plant, fulfilling Koch's postulates. As a result, the causal agent of the powdery mildew on L. vulgare was confirmed as G. ambrosiae (Schwein.) U. Braun & R.T.A. Cook, based on the current taxonomy and nomenclature of this species by Qiu et al. (2020).. Previously powdery mildew collections on L. vulgare have been reported as Golovinomyces cichoracearum (≡ Erysiphe cichoracearum) s. lat. in Estonia, Finland, Germany, and Switzerland, Golovinomyces biocellatus in Spain, and Podosphaera fusca (probably P. xanthii according to the current taxonomy) in the former Soviet Union (now Russia and adjacent countries) (Farr and Rossman 2022). This study is the first report of powdery mildew disease caused by G. ambrosiae on L. vulgare in Korea. Qiu et al. (2020) confirmed the occurrence of G. ambrosiae on L. maximum, another species of the genus Leucanthemum. As powdery mildew causes damage to the cultivation of L. vulgare by loss of ornamental value, appropriate control measures should be developed.

First Report of Powdery Mildew Caused by Golovinomyces ambrosiae on New York Aster (Symphyotrichum novi-belgii) in Korea.

Symphyotrichum novi-belgii (L.) G.L. Nesom (syn. Aster novi-belgii L.), known as New York aster, is a perennial herb used in gardens and as a potted plant. The plant is native to North America but has been developed into various horticultural varieties. In Korea, it is one of the most common plants used for autumn bloom. In September 2011, New York asters (variety unknown) showing typical signs of powdery mildew were observed in a public garden in Seoul, Korea. Since then, the disease on New York asters has been continuously found in parks and flower markets in different regions of Korea. Voucher specimens (n=3) were deposited in the Korea University Herbarium (KUS-F 30752, 31865, and 32103). On leaves, circular to irregular white patches appeared which subsequently showed abundant hyphal growth on both sides of the leaves and on young stems and inflorescences, reducing the aesthetic value and vigor of the plants affected. Hyphae were septate, branched, and 4 to 8 µm wide. Appressoria on the mycelium were nipple-shaped. Conidiophores measured 110 to 200 × 9 to 11.5 µm, were simple, and produced 2 to 5 immature conidia in chains with a sinuate outline, followed by 2 to 3 cells. Foot-cells of conidiophores were straight, cylindric, and 55 to 125 µm long. Conidia were hyaline, ellipsoid to barrel-shaped, measured 22 to 52 × 15 to 20 µm (length/width ratio = 1.5-2.5), lacked distinct fibrosin bodies, and produced germ tubes on the subterminal position, with reticulate wrinkling of the outer walls. No chasmothecia were observed. The structures described above were typical of the Oidium subgenus Euoidium anamorph of the genus Golovinomyces, and the fungus measurements were consistent with those of G. ambrosiae (Schwein.) U. Braun & R.T.A. Cook (Braun and Cook 2012, Qiu et al. 2020). To confirm the identity of the causal fungus, the internal transcribed spacer (ITS) and large subunit (LSU) regions of rDNA were amplified with primers PM10/ITS4 for ITS and PM3/TW14 for LSU (Mori et al. 2000, Bradshaw and Tobin 2020). The resulting sequences were deposited in GenBank (Accession No. OP028065-7 for ITS and OP028053-5 for LSU). A GenBank BLAST search of these sequences revealed 100% identity with sequences of G. ambrosiae on many asteraceous plants, including S. novi-belgii from China (MK452575-9 for ITS and MK452648-52 for LSU). Pathogenicity was confirmed through inoculation by gently pressing diseased leaves onto leaves of five healthy potted New York aster plants. Five non-inoculated plants served as controls. Plants were maintained in an incubator at 24°C. Inoculated plants developed signs and symptoms after three weeks, whereas the control plants remained symptomless. The fungus present on the inoculated plants was morphologically identical to that observed initially on diseased plants, fulfilling Koch's postulates. The powdery mildew infections of S. novi-belgii associated with G. ambrosiae have been widely known in Europe and North America but only recently in China (Qiu et al. 2020, Farr and Rossman 2022). In Japan, Podosphaera fuliginea was known to be associated with powdery mildew of S. novi-belgii (Farr and Rossman 2022). To our knowledge, this is the first report of powdery mildew caused by G. ambrosiae on S. novi-belgii in Korea. The powdery mildew on this ornamental plant can be considered a severe threat.

First Report of Powdery Mildew Caused by Golovinomyces ambrosiae on Solanum carolinense in Korea.

Solanum carolinense L. (Solanaceae) is a perennial herbaceous plant native to the southeastern United States. The plant has been invasive in Europe, Australia, and Asia. It was accidentally introduced to Korea in the 1960s (Oh et al. 2002) and is now widely naturalized mostly in the southern area of the Korean peninsula. Since 2002, it has been designated as one of 'harmful non-indigenous plants' by the Korean Ministry of Environment due to its adverse effects on native plants. In September 2014, several S. carolinense plants were found infested with a powdery mildew disease in Busan, which was the first for Korea. Later in 2020-2022, hundreds of plants were continuously observed with an approximately 50% disease incidence in Jeonju, Korea. Symptoms first appeared as circular to irregular white patches, which subsequently coalesced to develop into abundant hyphal growth on both sides of the leaves. Representative voucher specimens were deposited in the Korea University herbarium (KUS-F28240 and F32541). Hyphal appressoria were nipple-shaped. Conidiophores were cylindrical, 110 to 190 × 10 to 12 µm, and produced 2 to 5 immature conidia in chains with a sinuate outline. Foot-cells of conidiophores were straight, cylindrical, and 58 to 90 µm long, followed by 2 to 3 cells. Conidia were ellipsoid to barrel-shaped, 29 to 36 × 15 to 20 µm (l/w 1.6 to 2.0), and devoid of distinct fibrosin bodies. Germ tubes were at the perihilar position of the conidia. Sexual stage was not developed. These morphological characteristics are consistent with those of Golovinomyces ambrosiae (Schwein.) U. Braun & R.T.A. (Braun and Cook 2012). Sequences of the internal transcribed spacer (ITS) region and large subunit (LSU) gene of rDNA were determined using primer pairs ITS1/PM6 and PM3/TW14, respectively (Bradshaw and Tobin 2020). A comparison of the resulting sequences using the BLASTn algorithm showed 100% identity with reference sequences of G. ambrosiae (MT355556, AB769425) and G. spadiceus (MN365027) for ITS and LSU in NCBI. Obtained sequences were deposited in GenBank (Accession Nos: OP585651-OP585654). A Maximum parsimony tree was constructed based on ITS+LSU dataset consisting of 23 sequences. Our sequences were clustered with sequences of G. ambrosiae, G. latisporus and G. cichoracearum, and supported with 100% BS value. A pathogenicity test was performed by gently dusting conidia onto leaves of five healthy potted plants. Five non-inoculated plants served as controls. Powdery mildew colonies developed on all inoculated plants after 5 days, whereas the control plants remained symptomless. The fungus present on the inoculated leaves was morphologically identical to that observed on the originally diseased leaves, which supports Koch's postulate. Previously, Erysiphe cichoracearum (syn. of G. cichoracearum) was recorded on this plant in theUSA (Farr and Rossman 2022). Since G. cichoracearum has been divided into several distinct species (Takamatsu et al. 2013, Qiu et al. 2020), the current taxonomic position of the North American isolate is unknown. In Korea, G. ambrosiae was reported on several asteraceous hosts such as Bellis perennis, Brachyscome multifida, Helianthus annuus, H. salicifolius, and Verbena bonariensis (Farr and Rossman 2022). To our knowledge, this is the first report of powdery mildew on this plant outside the USA. According to our field observations, powdery mildew infestation had little effect on plant growth and vigor.   References: Braun, U., and Cook, R. T. A. 2012. Taxonomic Manual of the Erysiphales (Powdery Mildews), CBS Biodiversity Series No. 11. CBS, Utrecht, Netherlands. Bradshaw, M., and Tobin, P.C. 2020. Phytopathology 110:1248. Farr, D. F., and Rossman, A. Y. Fungal Databases, Syst. Mycol. Microbiol. Lab., Online publication. ARS, USDA. Retrieved October 5, 2022. Oh, S. M., et al. 2002. Kor. J. Weed Sci. 22:280. Qiu, P-L., et al. 2020. BMC Microbiology 20:51. Takamatsu S., et al. 2013. Mycologia 105:1135.

First Report of Powdery Mildew Caused by Golovinomyces ambrosiae on Erigeron annuus in Korea.

Erigeron annuus (L.) Pers., known as annual fleabane or eastern daisy fleabane, is native to North America and was unintentionally introduced to Korea in the 1910s (Park, 1995). It is now widely naturalized throughout Korea and was designated as one of the ten major introduced plants in Korea by the Korea National Arboretum. In September 2012, several dozen annual fleabanes were found to be heavily infected with powdery mildew. Symptoms first appeared as circular to irregular white patches, which subsequently showed abundant hyphal growth on both sides of the leaves. The same symptoms have continuously been found on annual fleabane throughout the country, where the disease incidence was often higher than 80%. Five voucher specimens were deposited in the Korea University Herbarium (KUS-F30208, 31414, 31774, 31784 and 32003). Hyphae were septate, branched, and 4.5 to 6.7 µm wide. Appressoria on the mycelium were lobed. Conidiophores (n = 30), measured 154 to 215 × 9 to 12.5 µm, were simple and produced 2 to 4 immature conidia in chains with a sinuate outline, followed by 2 to 3 cells. Foot-cells of conidiophores were straight, cylindrical, and 40 to 98 µm long. Conidia (n = 30) were hyaline, ellipsoid to barrel-shaped, measured 25.3 to 35.8 × 13 to 17 µm (length/width ratio = 1.62 to 2.31), lacked distinct fibrosin bodies, and showed reticulate wrinkling of the outer walls. Primary conidia were apically rounded and basally truncated and generally smaller than the secondary conidia. Germ tubes were produced on the subterminal position of conidia. No chasmothecia were observed. The structures described above were typical of the Euoidium anamorph of the genus Golovinomyces, and the fungus measurements were compatible with those of G. ambrosiae (Schwein.) U. Braun & R.T.A. Cook (Qiu et al., 2020). To confirm the identity of the causal fungus, the internal transcribed spacer (ITS) and large subunit (LSU) regions of rDNA from the five herbarium specimens were amplified with primers PM10/ITS4 for ITS and PM3/TW14 for LSU (Bradshaw and Tobin, 2020; Mori et al., 2000; White et al., 1990) and sequenced directly. The resulting sequence was deposited in GenBank (Accession No. OP788040-4 for ITS and OP788045-9 for LSU). Comparison with the sequences available in the GenBank database revealed that the isolates showed 100% sequence similarity with those of G. ambrosiae from the family Asteraceae (e.g., MT355557, MF612182, etc.). Pathogenicity was confirmed through inoculation by gently pressing diseased leaves onto the leaves of five healthy potted plants. Five non-inoculated plants served as controls. Plants were maintained in a greenhouse at 22 to 28°C. Inoculated plants developed signs and symptoms after seven days, whereas the control plants remained healthy. The fungus present on the inoculated plants was morphologically identical to that observed initially on diseased plants, fulfilling Koch's postulates. Powdery mildew infections of Erigeron spp. associated with Golovinomyces species have been known in the United States, France, and China (Farr and Rossman, 2022). To our knowledge, this is the first report of powdery mildew disease caused by G. ambrosiae on E. annuus outside of North America as well as in Korea. According to our field observation, powdery mildew infections were found only on annual fleabanes growing in shady areas, not in sunny places.

JNC-1043, a Novel Podophyllotoxin Derivative, Exerts Anticancer Drug and Radiosensitizer Effects in Colorectal Cancer Cells.

The objective of this study was to determine whether (5S)-5-(4-benzyloxy-3,5-dimethoxy-phenyl)-5,9-dihydro-8H-furo [3',4':6,7] naphtho [2,3-d] [1,3]dioxol-6-one (JNC-1043), which is a novel chemical derivative of ß-apopicropodophyllin, acts as a novel potential anticancer reagent and radiosensitizer in colorectal cancer (CRC) cells. Firstly, we used MTT assays to assess whether JNC-1043 could inhibit the cell proliferation of HCT116 and DLD-1 cells. The IC50 values of these cell lines were calculated as 114.5 and 157 nM, respectively, at 72 h of treatment. Using doses approximating the IC50 values, we tested whether JNC-1043 had a radiosensitizing effect in the CRC cell lines. Clonogenic assays revealed that the dose-enhancement ratios (DER) of HCT116 and DLD-1 cells were 1.53 and 1.25, respectively. Cell-counting assays showed that the combination of JNC-1043 and γ-ionizing radiation (IR) enhanced cell death. Treatment with JNC-1043 or IR alone induced cell death by 50~60%, whereas the combination of JNC-1043 and IR increased this cell death by more than 20~30%. Annexin V-propidium iodide assays showed that the combination of JNC-1043 and IR increased apoptosis by more 30~40% compared to that induced by JNC-1043 or IR alone. DCFDA- and MitoSOX-based assays revealed that mitochondrial ROS production was enhanced by the combination of JNC-1043 and IR. Finally, we found that suppression of ROS by N-acetylcysteine (NAC) blocked the apoptotic cell death induced by the combination of JNC-1043 and IR. The xenograft model also indicated that the combination of JNC-1043 and IR increased apoptotic cell death in tumor mass. These results collectively suggest that JNC-1043 acts as a radiosensitizer and exerts anticancer effects against CRC cells by promoting apoptosis mediated by mitochondrial ROS.

Isolation, screening and identification of key components having intense insect repellent activity against Plodia interpunctella from four different medicinal plant materials.

BACKGROUND: Global warming and the indiscriminate use of pesticides have increased the propagation of the stored-product insect pests, leading to enormous losses in the agriculture and food industries. The most used insect repellents are synthetic derivatives; however, these have an adverse effect on human health as well as on the environment. Therefore, we attempted to find materials with insect repellent activity in natural products. The present study aimed to identify the single chemical component with intense insect repellent activity in extracts from four different Oriental medicinal plant materials: (i) Anethum graveolens L. (dill) seeds; (ii) Artemisia capillaris Thunb. (capillary wormwood) leaves; (iii) smoked Prunus mume Siebold & Zucc. (mume) fruits; and (iv) Rhus javanica L. (galls). RESULTS: As a result of the bioassay-guided fractionation of each extract against the Plodia interpunctella, stored-product insect, the n-hexane fraction of dill seeds extract was confirmed as the optimal fraction between all of the fractions. In total, 32 chemical components were identified from the n-hexane fraction of dill seeds by gas chromatography-mass spectrometry analysis, and the two main components were dillapiole (47.51%) and carvone (26.76%). Of the two components, dillapiole was confirmed as the key component playing an essential role in insect repellent activity. CONCLUSION: Our study suggests that dillapiole has the potential to be used as a natural insect repellent for the control of P. interpunctella infestation in agricultural and food products during distribution and storage. © 2021 Society of Chemical Industry.

Method for fast lipid reconstruction and removal processing in 1 H MRSI of the brain.

PURPOSE: To develop a new rapid spatial filtering method for lipid removal, fast lipid reconstruction and removal processing (FLIP), which selectively isolates and removes interfering lipid signals from outside the brain in a full-FOV 2D MRSI and whole-brain 3D echo planar spectroscopic imaging (EPSI). THEORY AND METHODS: FLIP uses regularized least-squares regression based on spatial prior information from MRI to selectively remove lipid signals originating from the scalp and measure the brain metabolite signals with minimum cross contamination. FLIP is a noniterative approach, thus allowing a rapid processing speed, and uses only spatial information without any spectral priors. The performance of FLIP was compared with the Papoulis-Gerchberg algorithm (PGA), Hankel singular value decomposition (HSVD), and fast image reconstruction with L2 regularization (L2). RESULTS: FLIP in both 2D and 3D MRSI resulted in consistent metabolite quantification in a greater number of voxels with less concentration variation than other algorithms, demonstrating effective and robust lipid-removal performance. The percentage of voxels that met quality criteria with FLIP, PGA, HSVD, and L2 processing were 90%, 57%, 29%, and 42% in 2D MRSI, and 80%, 75%, 76%, and 74% in 3D EPSI, respectively. The quantification results of full-FOV MRSI using FLIP were comparable to those of volume-localized MRSI, while allowing significantly increased spatial coverage. FLIP performed the fastest in 2D MRSI. CONCLUSION: FLIP is a new lipid-removal algorithm that promises fast and effective lipid removal with improved volume coverage in MRSI.

Spectral editing in 1 H magnetic resonance spectroscopy: Experts' consensus recommendations.

Spectral editing in in vivo 1 H-MRS provides an effective means to measure low-concentration metabolite signals that cannot be reliably measured by conventional MRS techniques due to signal overlap, for example, γ-aminobutyric acid, glutathione and D-2-hydroxyglutarate. Spectral editing strategies utilize known J-coupling relationships within the metabolite of interest to discriminate their resonances from overlying signals. This consensus recommendation paper provides a brief overview of commonly used homonuclear editing techniques and considerations for data acquisition, processing and quantification. Also, we have listed the experts' recommendations for minimum requirements to achieve adequate spectral editing and reliable quantification. These include selecting the right editing sequence, dealing with frequency drift, handling unwanted coedited resonances, spectral fitting of edited spectra, setting up multicenter clinical trials and recommending sequence parameters to be reported in publications.

Motion correction methods for MRS: experts' consensus recommendations.

Long acquisition times due to intrinsically low signal-to-noise ratio and the need for highly homogeneous B0 field make MRS particularly susceptible to motion or scanner instability compared with MRI. Motion-induced changes in both localization and shimming (ie B0 homogeneity) degrade MRS data quality. To mitigate the effects of motion three approaches can be employed: (1) subject immobilization, (2) retrospective correction, and (3) prospective real-time correction using internal and/or external tracking methods. Prospective real-time correction methods can simultaneously update localization and the B0 field to improve MRS data quality. While localization errors can be corrected with both internal (navigators) and external (optical camera, NMR probes) tracking methods, the B0 field correction requires internal navigator methods to measure the B0 field inside the imaged volume and the possibility to update the scanner shim hardware in real time. Internal and external tracking can rapidly update the MRS localization with submillimeter and subdegree precision, while scanner frequency and first-order shims of scanner hardware can be updated by internal methods every sequence repetition. These approaches are most well developed for neuroimaging, for which rigid transformation is primarily applicable. Real-time correction greatly improves the stability of MRS acquisition and quantification, as shown in clinical studies on subjects prone to motion, including children and patients with movement disorders, enabling robust measurement of metabolite signals including those with low concentrations, such as gamma-aminobutyric acid and glutathione. Thus, motion correction is recommended for MRS users and calls for tighter integration and wider availability of such methods by MR scanner manufacturers.