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Using Panax japonicus as research material, callus induction and culture were carried out, and high-yielding cell lines were screened to establish a suspension culture system that promotes callus growth and the accumulation of the "total saponins" (total content of triterpenoid glycosides or ginsenosides). Using the root as an explant, the medium for callus induction and proliferation was optimized by adjusting culture conditions (initial inoculation amount, carbon source, shaking speed, hormone concentration, culture time) and a high-yielding cell line with efficient proliferation and high total saponins content was screened out. The conditions of suspension culture were refined to find out the most suitable conditions for the suspension culture of callus, and finally, the suspension culture system was established. We found that the lowest (5%) contamination rate was achieved by disinfecting the fresh roots with 75% alcohol for 60 s, followed by soaking in 10% NaClO for 15 min. The highest induction rate (88.17%) of callus was obtained using the medium MS + 16.11 μmol·L−1 NAA + 13.32 μmol·L−1 6-BA + 30.0 g·L−1 sucrose + 7.5 g·L−1 agar. The callus was loose when the callus subcultured on the proliferation medium (MS + 5.37 μmol·L−1 NAA + 13.32 μmol·L−1 6-BA + 30.0 g·L−1 sucrose + 3.8 g·L−1 gellan gum) for 21 days. The callus growth was cultured in a liquid growth medium (MS + 5.37 μmol·L−1 NAA + 13.32 μmol·L−1 6-BA + 30.0 g·L−1 sucrose) with an initial inoculation amount of 40 g·L−1, a shaking speed of 110 r/min and darkness. Cell growth was fastest with a culture period of 21 days. We replaced the growth medium with the production medium (MS + 5.37 μmol·L−1 NAA + 13.32 μmol·L−1 6-BA + 30.0 g·L−1 glucose) for maximum accumulation of total saponins. [Conclusion] A callus induction and suspension culture system for the root of P. japonicus was established. In this way, we can promote the accumulation of total saponins in callus cells and provide a basis for large-scale cell culture and industrial production of medicinal total saponins. [ABSTRACT FROM AUTHOR]

It is known that electrostatic discharge (ESD) is one of the frequent causes of integrated circuit failure and loss of spacecraft. However, the danger is not only the pulse itself but also the cross talk from it at the near (NEXT) and far (FEXT) ends. To investigate the possibility of their attenuating by meander line (ML) with a broadside coupling, a coupled microstrip line (MSL) was studied. As a result, the structure with a protected active line appeared to be the most promising. Also, the levels of NEXT and FEXT in it do not exceed 2% and 1.5% of half of the e.m.f. at s = 1000 µm, and when s = 100 µm 10% and 3%. In addition to evaluating signal attenuation, N-norms were analyzed as well. The most noteworthy is the nonlinear nature of the change in N2 depending on s. It is also notable that the proposed protection of the line from cross talk leads to a decrease in N1, N2, and N5. However, N3 and N4 increase at the same time. [ABSTRACT FROM AUTHOR]

Summary In this article, we investigated a new structure of a protective meander line (ML): a meander microstrip line (MSL) with two passive conductors. The existing theory of ultra‐short pulse (USP) attenuation in MLs is presented for the first time. Based on this theory, we determined the number of decomposed pulses at the output of the MSL line with two passive conductors, and, for the first time, formulated the conditions for pulse decomposition in the line. The folding of the MSL line into non‐core turns was studied in detail. As a result of this article, we proposed a new theory that involves the utilization of additional groups of decomposed pulses for enhanced USP attenuation. These additional groups were thoroughly examined, and the delays of pulses from these groups were defined. This analysis allowed identifying the reason for their appearance. It was revealed that folding the ML into non‐core turns allows further attenuation of the USP amplitude, which increases with the increase of the number of non‐core turns. To validate the obtained simulation results, we performed experimental measurements and obtained good consistency of the results. The N‐norms analysis demonstrated that the combined use of such folding and passive conductors reduces the probability of electrical breakdown, arc discharge, and dielectric breakdown. The maximum USP attenuation at the output was 24.9 dB. As a result of useful signal integrity analysis, it is proposed to use a folded MSL together with a USB 2.0 “Full‐speed” interface with a data transfer rate of 12 Mbit/s. In addition, it is proposed to use such MSLs in DC power circuits. [ABSTRACT FROM AUTHOR]

Introduction: Panax vietnamensis is a valuable medicinal plant and a source of a broad spectrum of biologically active ginsenosides of different structural groups. Overexploitation and low adaptability to planation cultivation have made this species vulnerable to human pressure and prompted the development of cell cultivation in vitro as a sustainable alternative to harvesting wild plants for their bioactive components. Despite high interest in biotechnological production, little is known about themain factors affecting cell growth and ginsenoside biosynthesis of this species under in vitro conditions. In this study, the potential of cell cultures of P. vietnamensis as a biotechnological source of ginsenosides was was assessed. Methods: Six suspension cell lines that were developed from different sections of a single rhizome through a multi-step culture optimization process and maintained for over 3 years on media with different mineral salt base and varying contents of auxins and cytokinins. These cell lines were evaluated for productivity parameters and cytological characteristics. Ginsenoside profiles were assessed using a combination of the reversed-phase ultra-high-performance liquid chromatography-Orbitrap-tandem mass spectrometry (UHPLC-Orbitrap-MS/MS) and ultra-performance liquid chromatography-time of flight-mass spectrometry (UPLC-TOF-MS). Results: All lines demonstrated good growth with a specific growth rate of 0.1-0.2 day-1, economic coefficient of 0.31-0.70, productivity on dry weight (DW) of 0.30-0.83 gDW (L·day)-1, and maximum biomass accumulation varying from 10 to 22 gDW L-1. Ginsenosides of the protopanaxadiol (Rb1, Rb2/Rb3, malonyl-Rb1, and malonyl-Rb2/Rb3), oleanolic acid (R0 and chikusetsusaponin IV), and ocotillol (vinaginsenoside R1) groups and their isomers were identified in cell biomass extracts. Chikusetsusaponin IV was identified in P. vietnamensis cell culture for the first time. Discussion: These results suggest that suspension cell cultures of Vietnamese ginseng have a high potential for the biotechnological production of biomass containing ginsenosides, particularly of the oleanolic acid and ocotillol groups. [ABSTRACT FROM AUTHOR]

The cultivation of plant cells in large-scale bioreactor systems has long been considered a promising alternative for the overexploitation of wild plants as a source of bioactive phytochemicals. This idea, however, faced multiple constraints upon realization, resulting in very few examples of technologically feasible and economically effective biotechnological companies. The bioreactor cultivation of plant cells is challenging. Even well-growing and highly biosynthetically potent cell lines require a thorough optimization of cultivation parameters when upscaling the cultivation process from laboratory to industrial volumes. The optimization includes, but is not limited to, the bioreactor's shape and design, cultivation regime (batch, fed-batch, continuous, semi-continuous), aeration, homogenization, anti-foaming measures, etc., while maintaining a high biomass and metabolite production. Based on the literature data and our experience, the cell cultures often demonstrate cell line- or species-specific responses to parameter changes, with the dissolved oxygen concentration (pO2) and shear stress caused by stirring being frequent growth-limiting factors. The mass transfer coefficient also plays a vital role in upscaling the cultivation process from smaller to larger volumes. The Experimental Biotechnological Facility at the K.A. Timiryazev Institute of Plant Physiology has operated since the 1970s and currently hosts a cascade of bioreactors from the laboratory (20 L) to the pilot (75 L) and a semi-industrial volume (630 L) adapted for the cultivation of plant cells. In this review, we discuss the most appealing cases of the cell cultivation process's adaptation to bioreactor conditions featuring the cell cultures of medicinal plants Dioscorea deltoidea Wall. ex Griseb., Taxus wallichiana Zucc., Stephania glabra (Roxb.) Miers, Panax japonicus (T. Nees) C.A.Mey., Polyscias filicifolia (C. Moore ex E. Fourn.) L.H. Bailey, and P. fruticosa L. Harms. The results of cell cultivation in bioreactors of different types and designs using various cultivation regimes are covered and compared with the literature data. We also discuss the role of the critical factors affecting cell behavior in bioreactors with large volumes. [ABSTRACT FROM AUTHOR]

Polyscias fruticosa (L.) Harms, or Ming aralia, is a medicinal plant of the Araliaceae family, which is highly valued for its antitoxic, anti-inflammatory, analgesic, antibacterial, anti-asthmatic, adaptogenic, and other properties. The plant can be potentially used to treat diabetes and its complications, ischemic brain damage, and Parkinson's disease. Triterpene glycosides of the oleanane type, such as 3-O-[β-D-glucopyranosyl-(1→4)-β-D-glucuronopyranosyl] oleanolic acid 28-O-β-D-glucopyranosyl ester (PFS), ladyginoside A, and polysciosides A-H, are mainly responsible for biological activities of this species. In this study, cultivation of the cell suspension of P. fruticosa in 20 L bubble-type bioreactors was attempted as a sustainable method for cell biomass production of this valuable species and an alternative to overexploitation of wild plant resources. Cell suspension cultivated in bioreactors under a semi-continuous regime demonstrated satisfactory growth with a specific growth rate of 0.11 day−1, productivity of 0.32 g (L · day)−1, and an economic coefficient of 0.16 but slightly lower maximum biomass accumulation (~6.8 g L−1) compared to flask culture (~8.2 g L−1). Triterpene glycosides PFS (0.91 mg gDW−1) and ladyginoside A (0.77 mg gDW−1) were detected in bioreactor-produced cell biomass in higher concentrations compared to cells grown in flasks (0.50 and 0.22 mg gDW−1, respectively). In antibacterial tests, the minimum inhibitory concentrations (MICs) of cell biomass extracts against the most common pathogens Staphylococcus aureus, methicillin-resistant strain MRSA, Pseudomonas aeruginosa, and Escherichia coli varied within 250–2000 µg mL−1 which was higher compared to extracts of greenhouse plant leaves (MIC = 4000 µg mL−1). Cell biomass extracts also exhibited antioxidant activity, as confirmed by DPPH and TEAC assays. Our results suggest that bioreactor cultivation of P. fruticosa suspension cell culture may be a perspective method for the sustainable biomass production of this species. [ABSTRACT FROM AUTHOR]

Purpose: Low-grade intermediate-risk nonmuscle-invasive bladder cancer is a chronic illness commonly treated by repetitive transurethral resection of bladder tumor. We compared the efficacy and safety of intravesical chemoablation with UGN-102 (a reverse thermal gel containing mitomycin), with or without subsequent transurethral resection of bladder tumor, to transurethral resection of bladder tumor alone in patients with low-grade intermediate-risk nonmuscle-invasive bladder cancer. Materials and Methods: This prospective, randomized, phase 3 trial recruited patients with new or recurrent low-grade intermediate-risk nonmuscle-invasive bladder cancer to receive initial treatment with either UGN-102 on weeks or transurethral resection of bladder tumor. Patients were followed quarterly by endoscopy, cytology, and for-cause biopsy. The primary end point was disease-free survival. All patients were followed for adverse events. Results: Trial enrollment was halted by the sponsor to pursue an alternative development strategy after 282 of a planned 632 patients were randomized to UGN-102 subsequent transurethral resection of bladder tumor (n[142) or transurethral resection of bladder tumor monotherapy (n[140), rendering the trial underpowered to perform hypothesis testing. Patients were predominantly male and 65 years of age. Tumor-free complete response 3 months after initial treatment was achieved by 92 patients (65%) who received UGN-102 and 89 patients (64%) treated by transurethral resection of bladder tumor. The estimated probability of disease-free survival 15 months after randomization was 72% for UGN-102 transurethral resection of bladder tumor and 50% for transurethral resection of bladder tumor (hazard ratio 0.45). The most common adverse events (incidence 10%) in the UGN-102 group were dysuria, micturition urgency, nocturia, and pollakiuria. Conclusions: Primary, nonsurgical chemoablation with UGN-102 for the management of low-grade intermediate-risk nonmuscle-invasive bladder cancer offers a potential therapeutic alternative to immediate transurethral resection of bladder tumor monotherapy and warrants further investigation. [ABSTRACT FROM AUTHOR]

The effects of methyl jasmonate (MeJ) on growth and taxoid formation in the cell culture of Taxus wallichiana were investigated to elucidate the specifics of phytohormone action in dedifferentiated plant cells in vitro. The characteristics of the same suspension cell culture were compared in 2017 (the «young» culture) and in 2022 (the «old» culture)—1.5 or 6 years after culture induction, respectively. MeJ (100 µM) is added to the cell suspension at the end of the exponential growth phase. Cell culture demonstrated good growth (dry weight accumulation 10–18 g/L, specific growth rate µ = 0.15–0.35 day−1) regardless of its «age», cultivation system, and MeJ addition. UPLC-ESI-MS analysis revealed the presence of C14-hydroxylated taxoids (yunnanxane, taxuyunnanine C, sinenxane C, and sinenxane B) in the cell biomass. The content of C14-OH taxoids increased from 0.2–1.6 mg/gDW in «young» culture to 0.6–10.1 mg/gDW in «old» culture. Yunnanxane was the main compound in «young» culture, while sinenxane C predominated in «old» culture. Without elicitation, small amounts of C13-OH taxoids (<0.05 mg/gDW) were found only in «young» cultures. MeJ addition to «young» culture had no effect on the content of C14-OH taxoids but caused a 10-fold increase in C13-OH taxoid production (up to 0.12–0.19 mg/gDW, comparable to the bark of yew trees). By contrast, MeJ added to «old» culture was not beneficial for the production of C13-OH taxoids but notably increased the content of C14-OH taxoids (1.5–2.0 times in flasks and 5–8 times in bioreactors). These findings suggest that hormonal signaling in dedifferentiated yew cells grown in vitro is different from that in plants and can be affected by the culture's age. This might be a result of the high level of culture heterogeneity and constant auto-selection for intensive proliferation, which leads to the predominant formation of C14-OH taxoids versus C13-OH taxoids and a modified cell response to exogenous MeJ treatment. [ABSTRACT FROM AUTHOR]

Simple Summary: This review highlights six genetic collections of algae, cyanobacteria, and plant materials maintained at the Institute of Plant Physiology of the Russian Academy of Sciences (IPPRAS) since the 1950–1970s using in vitro and cryopreservation techniques. The in vitro collections conserve over 430 strains of algae and cyanobacteria, more than 200 transgenic and non-transgenic potato clones, 117 cell cultures, and 50 strains of hairy and adventitious root cultures of medicinal and model plant species. The IPPRAS cryobank of plant genetic resources preserves in vitro-derived germplasm and seeds of wild and cultivated plants from 457 species and 74 families. This review discusses the collections' major activities and their extensive use in research, biotechnological interventions, commercial application, and biodiversity conservation. We also emphasize the role of in vitro collections as a genetic basis for green biotechnologies. Ex situ collections of algae, cyanobacteria, and plant materials (cell cultures, hairy and adventitious root cultures, shoots, etc.) maintained in vitro or in liquid nitrogen (−196 °C, LN) are valuable sources of strains with unique ecological and biotechnological traits. Such collections play a vital role in bioresource conservation, science, and industry development but are rarely covered in publications. Here, we provide an overview of five genetic collections maintained at the Institute of Plant Physiology of the Russian Academy of Sciences (IPPRAS) since the 1950–1970s using in vitro and cryopreservation approaches. These collections represent different levels of plant organization, from individual cells (cell culture collection) to organs (hairy and adventitious root cultures, shoot apices) to in vitro plants. The total collection holdings comprise more than 430 strains of algae and cyanobacteria, over 200 potato clones, 117 cell cultures, and 50 strains of hairy and adventitious root cultures of medicinal and model plant species. The IPPRAS plant cryobank preserves in LN over 1000 specimens of in vitro cultures and seeds of wild and cultivated plants belonging to 457 species and 74 families. Several algae and plant cell culture strains have been adapted for cultivation in bioreactors from laboratory (5–20-L) to pilot (75-L) to semi-industrial (150–630-L) scale for the production of biomass with high nutritive or pharmacological value. Some of the strains with proven biological activities are currently used to produce cosmetics and food supplements. Here, we provide an overview of the current collections' composition and major activities, their use in research, biotechnology, and commercial application. We also highlight the most interesting studies performed with collection strains and discuss strategies for the collections' future development and exploitation in view of current trends in biotechnology and genetic resources conservation. [ABSTRACT FROM AUTHOR]

The genus Ajuga (Lamiaceae) is rich in medicinally important species with biological activities ranging from anti-inflammatory, antitumor, neuroprotective, and antidiabetic to antibacterial, antiviral, cytotoxic, and insecticidal effects. Every species contains a unique and complex mixture of bioactive metabolites—phytoecdysteroids (PEs), iridoid glycosides, withanolides, neo-clerodane terpenoids, flavonoids, phenolics, and other chemicals with high therapeutic potential. Phytoecdysteroids, the main compounds of interest, are natural anabolic and adaptogenic agents that are widely used as components of dietary supplements. Wild plants remain the main source of Ajuga bioactive metabolites, particularly PEs, which leads to frequent overexploitation of their natural resources. Cell culture biotechnologies offer a sustainable approach to the production of vegetative biomass and individual phytochemicals specific for Ajuga genus. Cell cultures developed from eight Ajuga taxa were capable of producing PEs, a variety of phenolics and flavonoids, anthocyanins, volatile compounds, phenyletanoid glycosides, iridoids, and fatty acids, and demonstrated antioxidant, antimicrobial, and anti-inflammatory activities. The most abundant PEs in the cell cultures was 20-hydroxyecdysone, followed by turkesterone and cyasterone. The PE content in the cell cultures was comparable or higher than in wild or greenhouse plants, in vitro-grown shoots, and root cultures. Elicitation with methyl jasmonate (50–125 µM) or mevalonate and induced mutagenesis were the most effective strategies that stimulated cell culture biosynthetic capacity. This review summarizes the current progress in cell culture application for the production of pharmacologically important Ajuga metabolites, discusses various approaches to improve the compound yield, and highlights the potential directions for future interventions. [ABSTRACT FROM AUTHOR]

Plant cell cultures of various yew species are a profitable source of taxoids (taxane diterpenoids) with antitumor activity. So far, despite intensive studies, the principles of the formation of different groups of taxoids in cultured in vitro plant cells have not been fully revealed. In this study, the qualitative composition of taxoids of different structural groups was assessed in callus and suspension cell cultures of three yew species (Taxus baccata, T. canadensis, and T. wallichiana) and two T. × media hybrids. For the first time, 14-hydroxylated taxoids were isolated from the biomass of the suspension culture of T. baccata cells, and their structures were identified by high-resolution mass spectrometry and NMR spectroscopy as 7β-hydroxy-taxuyunnanin C, sinenxane C, taxuyunnanine C, 2α,5α,9α,10β,14β-pentaacetoxy-4(20), 11-taxadiene, and yunnanxane. UPLC–ESI-MS screening of taxoids was performed in more than 20 callus and suspension cell lines originating from different explants and grown in over 20 formulations of nutrient media. Regardless of the species, cell line origin, and conditions, most of the investigated cell cultures retained the ability to form taxane diterpenoids. Nonpolar 14-hydroxylated taxoids (in the form of polyesters) were predominant under in vitro culture conditions in all cell lines. These results, together with the literature data, suggest that dedifferentiated cell cultures of various yew species retain the ability to synthesize taxoids, but predominantly of the 14-OH taxoid group compared to the 13-OH taxoids found in plants. [ABSTRACT FROM AUTHOR]

Obesity, and its consequences for human health, is a huge and complicated problem that has no simple solution. The constant search for natural and safe compounds with systemic action that can be used for obesity prophylactics and treatment is hampered by the limited availability and variable quality of biomass of wild medicinal plants. Plant cell biotechnology is an alternative approach for the sustainable production of vegetative biomass or individual phytochemicals with high therapeutic potential. In this study, the suspension cell biomass of the medicinal plants, Dioscorea deltoidea Wall., Tribulus terrestris L., and Panax japonicus (T. Nees) C.A. Mey, produced in 20 L and 630 L bioreactors, were tested for therapeutic effects in rat models with alimentary-induced obesity. Three-month intake of water infusions of dry cell biomass (100 mg/g body weight) against the background of a hypercaloric diet reduced weight gain and the proportion of fat mass in the obese animals. In addition, cell biomass preparation reduced the intracellular dehydration and balanced the amounts of intra- and extracellular fluids in the body as determined by bioimpedance spectroscopy. A significant decrease in the glucose and cholesterol levels in the blood was also observed as a result of cell biomass administration for all species. Hypocholesterolemic activity reduced in the line P. japonicus > D. deltoidea > T. terrestris/liraglutide > intact group > control group. By the sum of parameters tested, the cell culture of D. deltoidea was considered the most effective in mitigating diet-induced obesity, with positive effects sometimes exceeding those of the reference drug liraglutide. A safety assessment of D. deltoidea cell phytopreparation showed no toxic effect on the reproductive function of the animals and their offspring. These results support the potential application of the biotechnologically produced cell biomass of medicinal plant species as safe and effective natural remedies for the treatment of obesity and related complications, particularly for the long-term treatment and during pregnancy and lactation periods when conventional treatment is often contraindicated. [ABSTRACT FROM AUTHOR]

In order to simplify the experimental procedure and treatment procedure, we preserved the embryonic callus (EC) of Fraxinus mandshurica more efficiently. In this paper, we established a method for cryopreservation of EC of F. mandshurica by vitrification. EC was subcultured for 7–10 days (d). Vigorous EC with good growth conditions were selected, and cryopreservation was performed by vitrification. The best pre-culture method was to pre-culture EC on 0.5 mol·L−1 sucrose medium for 3 d, load and culture in the liquid woody plant medium (WPM) supplemented with 2 mol·L−1 glycerol and 0.4 mol·L−1 sucrose for 60 min, then dehydrate in 2 mL of plant vitrification solution 2 (PVS2) (30% glycerol + 15% dimethyl sulfoxide (DMSO) + 15% ethylene glycol + 0.4 mol·L−1 sucrose + liquid WPM). EC was rewarmed in a 40 °C water bath for 2 min after cooling in liquid nitrogen. The procedure for cryopreservation of F. mandshurica EC by the vitrification method established in this experiment is relatively reliable. The results from the present study provide a technical reference for improving the cryopreservation of F. mandshurica EC. [ABSTRACT FROM AUTHOR]

The paper considers decomposition of an ultrashort pulse in a turn of a meander microstrip line with two passive conductors into a sequence of pulses of lower amplitude. Two circuit diagrams were discussed, differing in the location of the connection of half turns. Various boundary conditions (open circuit, short circuit and 50 Ω) of the ends of passive conductors were investigated and the optimal ones were selected according to the criterion of the minimum amplitude at the end of the line. The analysis of the influence of the geometric parameters of the line on the amplitude of the output signal was carried out. We found the optimal parameters of the structures, which ensure the decomposition of the ultrashort pulse and the minimization of its amplitude. Based on the simulation results, we obtained the attenuation of an ultrashort pulse (relative to half of the e.m.f.) in the first structure of 6.4 times, and in the second -- of 10.6 times. In addition, we determined the delays of each pulse and formulated the conditions the fulfilment of which allows for the decomposition of an ultrashort pulse into 11 pulses of lower amplitude. [ABSTRACT FROM AUTHOR]

The embryogenesis capacity of conifer callus is not only highly genotype-dependent, but also gradually lost after long-term proliferation. These problems have seriously limited the commercialization of conifer somatic embryogenesis (SE) technology. In this study, the responsive SE cell line (R-EC), the blocked SE cell line (B-EC), and the loss of SE cell line (L-EC) were studied. The morphological, physiological, transcriptomic, and metabolomic profiles of these three types of cells were analyzed. We found that R-EC had higher water content, total sugar content, and putrescine (Put) content, as well as lower superoxide dismutase (SOD) activity and H2O2 content compared to B-EC and L-EC. A total of 2566, 13,768, and 13,900 differentially expressed genes (DEGs) and 219, 253, and 341 differentially expressed metabolites (DEMs) were found in the comparisons of R-EC versus B-EC, R-EC versus B-EC, and B-EC versus L-EC, respectively. These DEGs and DEMs were mainly found to be involved in plant signal transduction, starch and sugar metabolism, phenylpropane metabolism, and flavonoid metabolism. We found that the AUX1 and AUX/IAA families of genes were significantly up-regulated after the long-term proliferation of callus, resulting in higher auxin content. Most phenylpropane and flavonoid metabolites, which act as antioxidants to protect cells from damage, were found to be significantly up-regulated in R-EC. [ABSTRACT FROM AUTHOR]

Somatic embryogenesis (SE), which leads to the formation of embryonic callus (EC) tissue, is the most promising method for large-scale production and selective breeding of woody plants. However, in many species, SE suffers from low proliferation rates, hindering the production of improved plant materials. One way of improving proliferation rates is achieved by improving the redox status of the culture medium. In this study, we investigated the effects of exogenous glutathione (GSH) and L-buthionine sulfoximine (BSO, the inhibitor of glutathione synthase) on the EC proliferation rate in Korean pine (Pinus koraiensis), using cell lines with both high (F: 001#-001) and low (S: 001#-010) proliferation potential. We found that exogenous GSH promoted cell proliferation in both cell lines, while exogenous BSO inhibited proliferation in both cell lines. At 35 d with exogenous GSH treatment, the fresh weight of F and S cell lines increased by 35.48% and 48.39%, respectively, compared with the control. The exogenous application of GSH increased the intracellular levels of GSH, total GSH (T-GSH), oxidized glutathione (GSSG), ascorbic acid (ASA), total ASA (T-ASA), and the ratios of GSH:T-GSH and ASA:T-ASA in both F and S cell lines. Furthermore, exogenous GSH increased the activity of both glutathione reductase (GR) and dehydroascorbate reductase (DHAR) while decreasing the activity of ascorbate peroxidase (APX) in both cell lines. It appears that the application of exogenous GSH promotes a reducing cultural environment, which is conducive to EC proliferation in Korean pine. By helping to reveal the mechanism whereby GSH regulates redox homeostasis in Korean pine EC cells, we have laid the foundation for a large-scale breeding of Korean pine somatic embryogenesis technology system. [ABSTRACT FROM AUTHOR]

During somatic embryogenesis of Pinus koraiensis, the ability of the embryogenic callus to produce embryos gradually decreases with long-term proliferative culture, which seriously affects large-scale application of this technology. In this study, embryogenic calli of Korean pine 1–100 cell line were used as materials. It was found that in the 7-day subculture cycle of embryogenic calli the somatic embryogenic potential of Korean pine remained for the longer time. In comparison with a subculture cycle of 14 days, indoleacetic acid (IAA), soluble sugar, and starch contents in embryogenic callus were higher with a subculture cycle of 7 days, while hydrogen peroxide (H2O2) content showed the opposite trend. Further, low levels of endogenous abscisic acid (ABA) and high levels of IAA could inhibit somatic embryogenesis of P. koraiensis calli. Among different carbon sources, maltose produced more storage materials and higher superoxide dismutase (SOD) and catalase (CAT) activities than sucrose, which was conducive to cell differentiation and somatic embryogenesis. The results revealed the physiological characteristics of the loss of embryogenic capacity of Korean pine embryogenic callus and provided a basis for the long-term maintenance of its somatic embryogenic capacity. [ABSTRACT FROM AUTHOR]

The article presents the results of calculating time responses of a meander line (ML) turn to pulse excitation. The responses were calculated at the ML nodes analytically and numerically, and demonstrated coincidence. Besides, the created prototype of the ML turn was measured and showed good qualitative and acceptable quantitative agreement with the simulation results. Analytical models were found to be promising since they may significantly accelerate the design of such MLs in contrast to numerical methods which provide costly multivariate simulation of the time response during optimization. [ABSTRACT FROM AUTHOR]

Many cell lines in the embryogenic callus cannot produce somatic embryos (SEs) even if they meet the optimal SE maturation culture conditions during conifer somatic embryogenesis. This phenomenon hinders the progress of the industrial-scale reproduction of conifers. Therefore, there is an urgent need to obtain morphological and physiological markers to screen embryogenic calli in response to SE maturation conditions. To detect cell lines with high somatic embryogenesis potential during the proliferation process, we counted the number of pro-embryos and early SEs (ESEs) in different cell lines and storage substances, endogenous hormones, and polyamine contents. The results showed that the yield of P. koraiensis SEs was heavily dependent on genotype (p = 0.001). There were high levels of PE III (pro-embryo III) number, ESE number, and soluble protein content, in the response cell lines (R cell lines), which were 1.6-, 3-, and 1.1-fold those of the obstructive cell lines (B cell lines), respectively. The B cell line had high levels of starch, auxin (IAA), Put, Spd, and putrescine: spermine (Put: Spm) compared to the R cell line. In addition, the numbers of PE III, ESEs, and soluble protein content were significantly positively correlated with SE yield. In contrast, the contents of starch, abscisic acid (ABA), Put, Spm, and Spd were significantly negatively correlated with SE yield. To ensure the accuracy of the results, we used nine cell lines to test the results. The PE III and ESE numbers and the Spm and Spd contents were positively correlated with SE yield, while the levels of starch, ABA, IAA, Put: Spd, and Put: Spm were negatively correlated with SE yield. Thus, we recommend using high PE III and ESEs as morphological indicators and low levels of starch, IAA, ABA, and Put: Spm as physiological markers to screen cell lines with a high somatic embryogenesis potential. In addition, we also found that the relationship between Spd, Spm, and SE yield was opposite in the two experimental results. Therefore, we speculate that the differences in Spd and Spm content are mainly affected by genotype. In conclusion, this study obtained the morphological and physiological markers of some high-somatic embryogenic cell lines by comparing the differences between nine somatic embryogenic cell lines. Our results can guide the improvement of conifer somatic embryogenesis technology and can provide a theoretical basis for accelerating the application of biotechnology in large-scale artificial breeding. [ABSTRACT FROM AUTHOR]

The study considers the problem of ensuring electromagnetic compatibility of EMI-based functional destruction means with other radioelectronic equipment as part of a complex for countering unmanned aerial vehicles. To solve this problem, it is proposed to create a methodology that combines a set of diverse approaches and methods. This study focuses on the use of hollow and thin passive conductors, the use of a magnetodielectric in a reflection symmetric modal filter, the use of reflection symmetric structures for decomposing the train of ultrashort pulses (USP), and the use of a meander line as a protective means against USPs. The main results that are expected to be obtained using the proposed approaches and methods are outlined. [ABSTRACT FROM AUTHOR]

The paper presents new analytical models for calculating the time response of a meander line (ML) turn with symmetrical cross-section and terminations to a pulse excitation. For the first time, the models were used to derive simple analytical models to equalize voltage amplitudes of the first pulses at the ML turn output: two pulses in homogeneous and three pulses in inhomogeneous dielectric filling. The obtained models were validated by quasistatic simulation. As a result, we theoretically proved that the maximum pulse amplitudes at the ML output are equal to 61.8% and 41.4% of the input amplitudes for the lines with homogeneous and inhomogeneous dielectric filling, respectively. The results could considerably simplify a computer-aided design, allowing for accelerated optimization of these structures without costly multivariate calculation of time response by numerical methods. [ABSTRACT FROM AUTHOR]

Cryopreservation is an important method for the excellent long-term preservation of plant germplasm. This study explores an optimal cryopreservation technology for the embryogenic callus of Fraxinus mandshurica to effectively maintain its genetic stability and morphogenesis potential. The optimal cryopreservation conditions were assessed using the embryogenic callus of F. mandshurica as the material, and the slow cooling method was optimized for its cryopreservation. The results indicated that the preculture of embryogenic callus in 0.4 mol·L−1 sorbitol solution for 20 h at room temperature, followed by its cryoprotection in 7.5% dimethyl sulfoxide solution at 0 °C for 90 min, constituted the optimal material treatment method. The freezing tube was placed in a −80 °C refrigerator for 2 h and then quickly put into liquid nitrogen for frozen storage. During thawing, the cryopreservation tube was taken out from liquid nitrogen, directly placed in a water bath at 40 °C for 2 min, and used for culturing on the woody plant media + 0.1 mg·L−1 6-benzyladenine + 0.15 mg·L−1 2, 4-dichlorophenoxyacetic acid. After cryopreservation using the slow cooling method, the highest survival rate of callus cells was 80.82%. The fresh weight reached 1.93 g after 60-day recovery culture. The regeneration rate and the proliferation coefficient of the callus were 100% and 2.79, respectively. The differentiation rate was 56.83%, and the emergence rate was 23.59%. The results provide a scientific basis for the long-term preservation of F. mandshurica germplasm resources. [ABSTRACT FROM AUTHOR]

This article describes a new approach to electrostatic discharge (ESD) protection based on usage of a turn of a microstrip meander line (ML). The proposed approach enables decomposing an ESD peak surge with the duration of about 4 ns into a sequence of smaller amplitude pulses. Using a quasi-static simulation of the meander turn time response to the excitation of the IEC 61000-4-2 standard ESD current source, we obtained the condition for such decomposition. In addition, we derived the condition for the overlapping of the additionally reflected odd mode pulse of the negative polarity on the even mode pulse to reduce the amplitude of the last pulse. As an example, the proposed approach is used in investigating the ESD pulse propagation along the ML with various parameters. We also found the optimal value of the turn length for the minimum output ESD voltage, which decreases as the distance between the ML half-turns decreases. The described approach and the formulated conditions provide the improvement of the protection against ESD by decreasing its magnitude by several times. The effectiveness of the new approach is confirmed by the electrodynamic simulation and prototype measurements. The new research results supplement the theoretical framework for ESD mitigation techniques and can be used in designing reliable, light-weight, low-cost, and radiation-resistant ESD protection devices. [ABSTRACT FROM AUTHOR]

Triaxial HTS AC power cables, that incorporates three HTS phases wound around a single core within a single cable is considering the optimal solution for low and medium voltages. Such a design permits to save expensive HTS conductor and to increase the power density transmitted. It is difficult to increase the transmission capacity of a triaxial cable by increasing its operating voltage and therefore, insulation thickness between phases. The other way is to increase the operation current by using a multilayer structure in each phase of the triaxial cable. This task demands a complicated optimization analysis and a precise manufacturing technology. Following our previous studies, we developed and tested the triaxial cable prototype with two layers per phase made of ReBCO wire. The optimal parameters of the cable (twist pitch, diameters of phases, etc.) have been determined using the numerical simulation methods developed. DC and AC tests of the cable has been performed. In the result, the feasibility to provide a uniform current distribution in a triaxial cable, each phase of which consists of two layers, has been demonstrated. With the outer diameter of ∼24 mm only, this is the most compact triaxial HTS power cable manufactured and tested up to date with currents up to 4 kA per phase. The anticipated power transfer with three phases of this cable can be as large as ∼34 MW. [ABSTRACT FROM AUTHOR]

Chemical diversity of secondary metabolites provides a considerable variety of pharmacological actions with a significant extension due to their combinations in plant extracts. Production of plant-derived medicinal products in cell cultures has advantages because of the efficient use of different biotic and abiotic elicitors and better control of the developmental processes. Using PASS software, we predicted biological activity spectra for phytoconstituents identified in cell cultures of Panax japonicus (12 molecules), Tribulus terrestris (4 molecules), and Dioscorea deltoidea (3 molecules). Mechanisms of action associated with the antihypoxic effect were predicted for the majority of molecules. PharmaExpert software allowed analyzing possible synergistic or additive effects of the combinations of phytoconstituents associated with the antihypoxic action. Experimental studies of the antihypoxic effect of the plants' extracts in water and ethanol have been performed in 3 animal models: Acute asphyctic hypoxia (AAH), Acute haemic hypoxia (AHeH), and Acute histotoxic hypoxia (AHtH). Effects of Panax japonicus and Tribulus terrestris preparations exceeded the activity of the reference drug Mexidol in the AHtH model. In the AHeH model, all preparations demonstrated moderate activity; the most potent has been observed for Dioscorea deltoidea. Thus, we found that experimental studies in animal models have confirmed the in silico prediction. [ABSTRACT FROM AUTHOR]

Zinc is the most abundant and important transition metal in plants; however, the dynamic aspects of zinc homeostasis in plant cells are poorly understood. In this study we explored the pool of labile exchangeable zinc complexes in plant cells, and the potential influence of changes in intracellular zinc availability on cellular physiology. Work was performed on cultivated cell extracts of Arabidopsis thaliana (L.) Heynh. and Thellungiella salsuginea (Pall.) O.E. Schulz grown under control (3.48 µM Zn2+), 10-fold Zn excess or Zn starvation conditions. The free and labile Zn contents in the extracts were then determined by fluorimetric titration. We observed for the first time that plant cells contain micromolar concentrations of labile zinc complexes that account for a low percentage of the total zinc content. Labile zinc is mainly protein bound. Zn starvation inhibits cell proliferation and leads to the disappearance of the labile zinc pool, whereas Zn excess drastically increases the labile zinc pool. Free Zn2+ is buffered at picomolar concentrations in the intracellular milieu, and the increase in free Zn2+ concentrations to low nanomolar values clearly modulates enzyme activity by direct reversible binding. Such increases in free Zn2+ can be achieved by the substantial influx of additional zinc or by the oxidation of zinc-binding thiols. The observed features of the labile zinc pool in plant cells suggest it has a role in intracellular zinc trafficking and zinc signalling. The dynamic aspects of zinc homeostasis in plant cells are poorly understood. We demonstrated for the first time that plant cells contain a pool of labile zinc complexes that control intracellular zinc availability and the physiological action of zinc ions. Our findings are crucial in understanding the mechanisms of intracellular zinc distribution and zinc regulatory action. [ABSTRACT FROM AUTHOR]

High-current superconducting links based on MgB2 superconductors are being developed at CERN for the feeding of the superconducting magnets of theLHCHigh-Luminosity project. TheMgB2 superconductors are very sensitive to the strain that unavoidably occurs during a cabling process. It is difficult to evaluate all the strains that can occur during cabling of MgB2 conductors, so the minimization of critical current degradation requires a step-by-step evaluation of current properties with the subsequent modification of some components of cable machines. This paper presents some practical results on cabling of MgB2 round wires and tapes in the nickel matrix from the Columbus Superconductor that are softer than other MgB2 wires. We compare the currents of the samples taken of the cables at different stages of the cabling with those at delivery, before, and after the modification of components of the cablingmachine. Temperature dependencies of critical currents measured in the range from 10 to 30 K are presented. [ABSTRACT FROM AUTHOR]

In the framework of the project where space in a cryostat is strictly limited, the high temperature superconductor (HTS) segments of the current leads have to be placed horizontally and in a scattered magnetic field. We developed the current leads optimization model for such conditions. In this paper, we present the results of optimization for 2000AHTS current leads, comprised of 2G HTS tapes and able to work in the magnetic field up to 2 T. The optimal parameters of the current leads segments have been determined using a numerical simulation. In order to approach the maximum efficiency, it is necessary to have a very good heat exchange between the current leads and evaporating helium gas. The impact of the external magnetic field on the heat leak from current leads into liquid helium is studied. [ABSTRACT FROM AUTHOR]

Decomposition of an ultrawideband (UWB) pulse into a sequence of pulses with lower amplitudes in a turn of a meander microstrip line has been experimentally proved to be an effective method of protection against UWB pulses for electronic equipment. It has been shown that the output signal of the line can be minimized by means of equalization of amplitudes of the first three pulses. It has been achieved due to optimization of coupling between half-turns of the line. The obtained attenuation of a pulse with full-width-at-half-maximum of 40 ps is 6.3 times. Combination of experimental and simulation methods is used to obtain the results in time and frequency domains. [ABSTRACT FROM PUBLISHER]

Triaxial HTS power cables are the optimal solution for low and medium voltages. This design permits to save expensive HTS conductor and to increase the power density transmitted. They could be used at medium voltages ∼10–20 kV for distribution grids. At relatively low voltages (<1–10 kV), triaxial cables could be used for ship propulsion systems or in electrical aircraft, where higher voltages are prohibited due to operational conditions. Prototypes of HTS “triaxial” cables made of both Bi-2223 and ReBaCuO HTS wires have been developed and tested in the Russian Scientific R&D Cable Institute. The calculations to optimize the cables with three superconducting layers and outer copper shield have been performed. The optimal parameters have been determined. The Bi-based 10-m cable has been inserted in a full-size flexible cryostat with current leads developed and has been tested at dc and ac conditions. The 4-m ReBaCuO cable has been tested in a laboratory cryostat and tested at dc and ac conditions also. AC tests of both cables were performed at different frequencies from ∼37 to ∼400 Hz. The cables designs, test results, and their analysis are presented. [ABSTRACT FROM PUBLISHER]

Ethylene is known to influence the cell cycle (CC) via poorly characterized roles whilst nitric oxide (NO) has well-established roles in the animal CC but analogous role(s) have not been reported for plants. As NO and ethylene signaling events often interact we examined their role in CC in cultured cells derived from Arabidopsis thaliana wild-type (Col-0) plants and from ethylene-insensitive mutant ein2-1 plants. Both NO and ethylene were produced mainly during the first 5 days of the sub-cultivation period corresponding to the period of active cell division. However, in ein2-1 cells, ethylene generation was significantly reduced while NO levels were increased. With application of a range of concentrations of the NO donor, sodium nitroprusside (SNP) (between 20 and 500 μM) ethylene production was significantly diminished in Col-0 but unchanged in ein2-1 cells. Flow cytometry assays showed that in Col-0 cells treatments with 5 and 10 μM SNP concentrations led to an increase in S-phase cell number indicating the stimulation of G1/S transition. However, at ≥20 μM SNP CC progression was restrained at G1/S transition. In the mutant ein2-1 strain, the index of S-phase cells was not altered at 5-10 μM SNP but decreased dramatically at higher SNP concentrations. Concomitantly, 5 μM SNP induced transcription of genes encoding CDKA;1 and CYCD3;1 in Col-0 cells whereas transcription of CDKs and CYCs were not significantly altered in ein2-1 cells at any SNP concentrations examined. Hence, it is appears that EIN2 is required for full responses at each SNP concentration. In ein2-1 cells, greater amounts of NO, reactive oxygen species, and the tyrosine-nitrating peroxynitrite radical were detected, possibly indicating NO-dependent post-translational protein modifications which could stop CC. Thus, we suggest that in Arabidopsis cultured cells NO affects CC progression as a concentration-dependent modulator with a dependency on EIN2 for both ethylene production and a NO/ethylene regulatory function. [ABSTRACT FROM AUTHOR]

This is a summary of a paper published in a medical journal that describes the results of a study called CheckMate 274. This study looked at a new treatment for muscle-invasive urothelial cancer, a type of cancer found in the urinary tract that has spread from the inner lining of the urinary tract or bladder and into the surrounding muscle wall where it can then spread to other parts of the body. The standard treatment for muscle-invasive urothelial cancer is surgery to remove affected parts of the urinary tract. However, cancer returns in more than half of people after this surgery. Adjuvant therapy is given to people after surgery with muscle-invasive urothelial cancer with a goal to reduce the risk of the cancer coming back; however, at the time this study started, there was no standard adjuvant treatment. In the CheckMate 274 study, researchers compared nivolumab with a placebo as an adjuvant treatment for people with muscle-invasive urothelial cancer. The aim of the study was to understand how well nivolumab worked to reduce the chance of the cancer returning after surgery. The study also looked at what side effects (unwanted or unexpected results or conditions that are possibly related to the use of a medication) people had with treatment. The results showed that people who received nivolumab versus placebo: Survived longer before the cancer was detected again, including people who had programmed death ligand-1 (shortened to PD-L1) on their cancer cells. Survived longer before a secondary cancer outside of the urinary tract was detected. Experienced no differences in health-related quality of life (the impact of the treatment on a person's mental and physical health). Had similar side effects to the people who received nivolumab in other studies. Clinical Trial Registration: NCT02632409 (ClinicalTrials.gov) [ABSTRACT FROM AUTHOR]

Recent therapeutic advances for managing low-risk prostate cancer include the active surveillance and focal treatment. However, locating a tumor and detecting its volume by adequate sampling is still problematic. Development of predictive biomarkers guiding individual therapeutic choices remains an ongoing challenge. At the same time, prostate cancer magnetic resonance imaging is gaining increasing importance for prostate diagnostics. The high morphological resolution of T2-weighted imaging and functional MRI methods may increase the specificity and sensitivity of diagnostics. Also, recent studies founded an ability of novel biomarkers to identify clinically insignificant prostate cancer, risk of progression, and association with poor differentiation and, therefore, with clinical significance. Probably, the above mentioned methods would improve tumor characterization in terms of its volume, aggressiveness, and focality. In this review, we attempted to evaluate the applications of novel imaging techniques and biomarkers in assessing the significance of the prostate cancer. [ABSTRACT FROM AUTHOR]