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Non-stoichiometric Li 0.35 MnO 2 nanoparticles with tetragonal-structure were successfully synthesized from MnCl 2 ·4H 2 O and KOH in LiOH aqueous solution, via chemical lithiation under liquid olefin atmosphere at 353 K. The microstructure and composition of the nanoparticles were characterized by X-ray diffraction, transmission electron microscopy, and inductively coupled plasma atom emission spectroscopy. The valence state of manganese in the sample was determined by the redox titration method. Further, the electrochemical performance of the sample as a cathode material was evaluated by galvanostatic measurements and cyclic voltammetry. The sample was found to exhibit a tetragonal structure with irregularly shaped grains, and grain diameters between 20 and 40 nm. The t-Li 0.35 MnO 2 prepared also exhibited high capacity as lithium ion cathode materials with an initial discharge capacity of 178.8 mA h g −1 and retained the discharge capacity at 131.7 mA h g −1 after 50 cycles. [ABSTRACT FROM AUTHOR]

To investigate the genetic basis of drought tolerance in soybean ( Glycine max L. Merr.) a recombinant inbred population with 184 F2:7:11 lines developed from a cross between Kefeng1 (drought tolerant) and Nannong1138-2 (drought sensitive) were tested under water-stressed and well-watered conditions in field and greenhouse trials. Traits measured included leaf wilting coefficient, excised leaf water loss and relative water content as indicators of plant water status and seed yield. A total of 40 quantitative trait loci (QTLs) were identified: 17 for leaf water status traits under drought stress and 23 for seed yield under well-watered and drought-stressed conditions in both field and greenhouse trials. Two seed yield QTLs were detected under both well-watered and drought-stressed conditions in the field on molecular linkage group H and D1b, while two seed yield QTLs on molecular linkage group C2 were found under greenhouse conditions. Several QTLs for traits associated with plant water status were identified in both field and greenhouse trials, including two leaf wilting coefficient QTLs on molecular linkage group A2 and one excised leaf water loss QTL on molecular linkage group H. Phenotypic correlations of traits suggested several QTLs had pleiotropic or location-linked associations. These results will help to elucidate the genetic basis of drought tolerance in soybean, and could be incorporated into a marker-assisted selection breeding program to develop high-yielding soybean cultivars with improved tolerance to drought stress. [ABSTRACT FROM AUTHOR]

Nodulation is the most efficient nitrate assimilation system in the ecosystem, while excessive fertilization has an increased nitrate inhibition effect; deciphering the nitrate signal transduction mechanism in the process is of the utmost importance. In this study, genome-wide analyses of the GmCEP genes were applied to identify nodulation-related CEP genes; 22 GmCEP family members were identified, while GmCEP6 was mainly expressed in nodules and significantly responded to nitrate treatment and rhizobium infection, especially in later stages. Overexpression and CRISPR-Cas9 were used to validate its role in nodulation. We found that GmCEP6 overexpression significantly increased the nodule number, while GmCEP6 knock-out significantly decreased the nodule number, which suggests that GmCEP6 functions as a positive regulator in soybean nodulation. qRT-PCR showed that alterations in the expression of GmCEP6 affected the expression of marker genes in the Nod factor signaling pathway. Lastly, the function of GmCEP6 in nitrate inhibition of nodulation was analyzed; nodule numbers in the GmCEP6-overexpressed roots significantly increased under nitrogen treatments, which suggests that GmCEP6 functions in the resistance to nitrate inhibition. The study helps us understand that GmCEP6 promotes nodulation and participates in the regulation of nitrate inhibition of nodulation, which is of great significance for high efficiency utilization of nitrogen in soybeans. [ABSTRACT FROM AUTHOR]

Soybean mosaic virus (SMV) is one of the main pathogens that can negatively affect soybean production and quality. To study the gene regulatory network of soybeans in response to SMV SC15, the resistant line X149 and susceptible line X97 were subjected to transcriptome analysis at 0, 2, 8, 12, 24, and 48 h post-inoculation (hpi). Differential expression analysis revealed that 10,190 differentially expressed genes (DEGs) responded to SC15 infection. Weighted gene co-expression network analysis (WGCNA) was performed to identify highly related resistance gene modules; in total, eight modules, including 2256 DEGs, were identified. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of 2256 DEGs revealed that the genes significantly clustered into resistance-related pathways, such as the plant–pathogen interaction pathway, mitogen-activated protein kinases (MAPK) signaling pathway, and plant hormone signal transduction pathway. Among these pathways, we found that the flg22, Ca2+, hydrogen peroxide (H2O2), and abscisic acid (ABA) regulatory pathways were fully covered by 36 DEGs. Among the 36 DEGs, the gene Glyma.01G225100 (protein phosphatase 2C, PP2C) in the ABA regulatory pathway, the gene Glyma.16G031900 (WRKY transcription factor 22, WRKY22) in Ca2+ and H2O2 regulatory pathways, and the gene Glyma.04G175300 (calcium-dependent protein kinase, CDPK) in Ca2+ regulatory pathways were highly connected hub genes. These results indicate that the resistance of X149 to SC15 may depend on the positive regulation of flg22, Ca2+, H2O2, and ABA regulatory pathways. Our study further showed that superoxide dismutase (SOD) activity, H2O2 content, and catalase (CAT) and peroxidase (POD) activities were significantly up-regulated in the resistant line X149 compared with those in 0 hpi. This finding indicates that the H2O2 regulatory pathway might be dependent on flg22- and Ca2+-pathway-induced ROS generation. In addition, two hub genes, Glyma.07G190100 (encoding F-box protein) and Glyma.12G185400 (encoding calmodulin-like proteins, CMLs), were also identified and they could positively regulate X149 resistance. This study provides pathways for further investigation of SMV resistance mechanisms in soybean. [ABSTRACT FROM AUTHOR]

The effect of salt damage on plants is mainly caused by the toxic effect of Na+. Studies showed that the secretory carrier membrane proteins were associated with the Na+ transport. However, the salt tolerance mechanism of secretory carrier protein (SCAMP) in soybean was yet to be defined. In this study, ten potential SCAMP genes distributed in seven soybean chromosomes were identified in the soybean genome. The phylogenetic tree of SCAMP domain sequences of several plants can divide SCAMPs into two groups. Most GmSCAMPs genes contained multiple Box4, MYB and MYC cis-elements indicated they may respond to abiotic stresses. We found that GmSCAMP1, GmSCAMP2 and GmSCAMP4 expressed in several tissues and GmSCAMP5 was significantly induced by salt stress. GmSCAMP5 showed the same expression patterns under NaCl treatment in salt-tolerant and salt-sensitive soybean varieties, but the induced time of GmSCAMP5 in salt-tolerant variety was earlier than that of salt-sensitive variety. To further study the effect of GmSCAMP5 on the salt tolerance of soybean plants, compared to GmSCAMP5-RNAi and EV-Control plants, GmSCAMP5-OE had less wilted leave and higher SPAD value. Compared to empty vector control, less trypan blue staining was observed in GmSCAMP5-OE leaves while more staining in GmSCAMP5-RNAi leaves. The Na+ of GmSCAMP5-RNAi plants leaves under NaCl stress were significantly higher than that in EV-Control plants, while significantly lower Na+ in GmSCAMP5-OE plants than in that EV-Control plants. The contents of leaves K+ of GmSCAMP5-RNAi, EV-Control, and GmSCAMP5-OE plants under NaCl stress were opposite to that of leaves Na+ content. Finally, salt stress-related genes NHX1, CLC1, TIP1, SOD1, and SOS1 in transformed hairy root changed significantly compared with the empty control. The research will provide novel information for study the molecular regulation mechanism of soybean salt tolerance. [ABSTRACT FROM AUTHOR]

Isoprenoids, a large kind of plant natural products, are synthesized by the mevalonate (MVA) pathway in the cytoplasm and the 2-C-methyl-d-erythritol 4-phosphate (MEP) pathway in plastids. As one of the rate-limiting enzymes in the MVA pathway of soybean (Glycine max), 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR) is encoded by eight isogenes (GmHMGR1–GmHMGR8). To begin, we used lovastatin (LOV), a specific inhibitor of GmHMGR, to investigate their role in soybean development. To further investigate, we overexpressed the GmHMGR4 and GmHMGR6 genes in Arabidopsis thaliana. The growth of soybean seedlings, especially the development of lateral roots, was inhibited after LOV treatment, accompanied by a decrease in sterols content and GmHMGR gene expression. After the overexpression of GmHMGR4 and GmHMGR6 in A. thaliana, the primary root length was higher than the wild type, and total sterol and squalene contents were significantly increased. In addition, we detected a significant increase in the product tocopherol from the MEP pathway. These results further support the fact that GmHMGR1–GmHMGR8 play a key role in soybean development and isoprenoid biosynthesis. [ABSTRACT FROM AUTHOR]

A natural α-1,6-glucan named BBWPW was identified from black beans. Cell viability assay showed that BBWPW inhibited the proliferation of different cancer cells, especially HeLa cells. Flow cytometry analysis indicated that BBWPW suppressed the HeLa cell cycle in the G2/M phase. Consistently, RT-PCR experiments displayed that BBWPW significantly impacts the expression of four marker genes related to the G2/M phase, including p21, CDK1, Cyclin B1, and Survivin. To explore the molecular mechanism of BBWPW to induce cell cycle arrest, a transcriptome-based target inference approach was utilized to predict the potential upstream pathways of BBWPW and it was found that the PI3K-Akt and MAPK signal pathways had the potential to mediate the effects of BBWPW on the cell cycle. Further experimental tests confirmed that BBWPW increased the expression of BAD and AKT and decreased the expression of mTOR and MKK3. These results suggested that BBWPW could regulate the PI3K-Akt and MAPK pathways to induce cell cycle arrest and ultimately inhibit the proliferation of HeLa cells, providing the potential of the black bean glucan to be a natural anticancer drug. [ABSTRACT FROM AUTHOR]

The symbiotic nitrogen fixation (SNF) of legumes is essential for their growth and development. However, the effects of SNF on the production of specific compounds in medicinal legumes remains unclear. In this study, we identified 364 differentially accumulated metabolites (DAMs) in Sophora flavescens roots triggered by SNF compared to non-inoculated control, including compounds like 6,7-Dihydroxy-4'-methoxy isoflavone, Puerarin, Biochanin A, Ginkgetin, Sieboldin, and Prunetin. A comparative transcriptomic analysis of nodulated Sophora flavescens roots and non-inoculated control revealed 9510 differentially expressed genes (DEGs). Integrating metabolomic and transcriptomic analysis of these DEGs and DAMs highlighted 37 genes associated with isoflavonoid biosynthesis. Notably, several key regulators in isoflavonoids biosynthesis were identified and confirmed by qRT-PCR. Overexpression of SfIF7GT in Sophora flavescens roots led to a significantly increase of the enzyme activity of flavonoids biosynthesis and flavonoid contents, including Genistin, Daidzin, ononin, Luteolin, Luteoloside, and Apigenin. These findings shed light on effects of SNF on the bioactive compounds in medicinal legumes, and offer valuable insights for reducing the amount of chemical fertilizer use and promoting efficient cultivation of medicinal legumes. • Nodulation enhances the growth of Sophora flavescens and triggers an increase in flavonoid contents in nodulated roots. • Nodulation orchestrates the expression of IF7GT , IF7MAT , IFS , HI4'OMT in regulating isoflavonoids biosynthesis. • Overexpression of SfIF7GT in Sophora flavescens roots leads to an increase in genistin, daidzin, luteolin, luteoloside, and apigenin. [ABSTRACT FROM AUTHOR]

Soybean saponin is one of the important secondary metabolites in seeds, which has various beneficial physiological functions to human health. GmSg-1 gene is the key enzyme gene for synthesizing class A saponins. It is of great significance to realize the visual and rapid detection of class A saponins at the genetic level. The hybridization chain reaction (HCR) was employed to the visual detection of GmSg-1 gene, which was implemented by changing the length of the target fragment to 92 bp and using the hairpin probes we designed to detect the GmSg-1a and GmSg-1b genes. The best condition of HCR reaction is hemin (1.2 μM), Triton X-100 (0.002%), ABTS (3.8 μM), and H2O2 (1.5 mM). It was found that HCR has high specificity for GmSg-1 gene and could be applied to the visual detection of different soybean cultivars containing Aa type, Ab type, and Aa/Ab type saponins, which could provide technical reference and theoretical basis for molecular breeding of soybean and development of functional soybean products. [ABSTRACT FROM AUTHOR]

Soybean mosaic virus (SMV) is the most prevalent viral pathogen of soybean worldwide that reduces seed quality and causes serious losses in yields. The accurate, rapid and early detection of SMV strains is crucial for screening SMV-resistant soybean varieties and controlling soybean mosaic disease timely. In this study, we report a loop-mediated isothermal amplification (LAMP) assay for visual and rapid detection of SMV-SC7, the major prevalent SMV strain in China, in soybean leaves. Specific primers were rationally designed and tested to detect the SMV-SC7 strain. The detection limit for SMV-SC7 can be as low as 10−4 ng/μL by the developed LAMP assay. These results were visualized by three indicators (SYBR green I, neutral red and hydroxy naphthol blue) with high fidelity. The high analytical performance of the LAMP assay was demonstrated with 21 soybean cultivars, among which 8 soybean cultivars were further inoculated with consistent results to those achieved by LAMP. This visual and rapid LAMP assay is highly promising for early detection of SMV-SC7-associated plant diseases. [Display omitted] • Early detection of SMV strains is crucial for preventing severe yield losses. • SMV-SC7 is traditionally detected by phenotype observation. • A colorimetric LAMP assay was developed for the detection of SMV-SC7. • The LAMP assay can identify SMV-SC7 earlier than phenotype observation. • The LAMP assay has great potential for field-friendly diagnostic testing. [ABSTRACT FROM AUTHOR]

A binuclear copper(II) complex [Cu(PDC)(phen)]2 · 2CH3OH · 1.5H2O (1) and a seven-coordinate manganese(II) complex [Mn(PDC)(phen)2] · CH3OH (2) (PDC = pyridine-2,6-dicarboxylate, phen = 1,10-phenanthroline) have been synthesized hydrothermally and characterized by elemental analyses, spectroscopic studies (IR and UV), and single-crystal X-ray diffraction. In 1, the binuclear copper(II) compound consists of two kinds of Cu(II) centers with five- and six-coordination environments by PDC and phen. The two Cu(II) ions are bridged by one PDC. In 2, Mn(II) is seven-coordinate by two phen and one PDC. [ABSTRACT FROM AUTHOR]

Abstract: Two new organic–inorganic hybrid compounds [Zn(phen)(SO4)(H2O)2] n (1) and [Cu(phen)(H2O)2]·SO4 (2) have been prepared by conventional aqueous solution synthesis and characterized by single-crystal X-ray diffraction, IR spectroscopy, thermal gravimetric analysis (TGA) and fluorescent spectroscopy. In compound 1, the sulfate group adopts bidentate mode to coordinate with two Zn(II) ions to form one-dimensional polymer. The one-dimensional polymers are further linked together via the intermolecular hydrogen-bonding and π–π stacking interactions to form a 3D supramolecular framework. Compound 2 is build up of discrete [Cu(phen)(H2O]2+ cations and SO4 2− anions to form a three-dimensional framework via hydrogen-bonding and π–π stacking interactions. Furthermore, the luminescent properties of both 1 and 2 were studied. The complexes 1 and 2 excited at 280nm wavelength produced characteristic luminescence features, arising maybe due to the π–π transitions. [Copyright &y& Elsevier]

In this paper, we report incorporation of the nanostructuration Single-Molecule Magnets (SMMs) Mn 3 into mesoporous aluminum-based metal-organic framework (MOF) [Al(OH)(SDC)] n (H 2 SDC ​= ​4,4′-stilbenedicarboxylic acid), known as CYCU-3. The successful incorporation was confirmed by PXRD, N 2 adsorption measurements and thermogravimetric analysis. EDX analysis indicated average 15 ​mol% insertion of SMMs, which is substantial higher than what was previously reported for SMM@silica composites. TGA measurements suggest that MOF can increase the SMM's thermal stability. Magnetic measurements reveal the preservation of the magnetic properties of SMMs inside MOF pores. The AC susceptibility data suggest an effective energy barrier of about 40 ​K for SMM@MOFs composites, slightly lower than those of pristine Mn 3 SMMs, which is about 55 ​K. Mn 3 SMMs cluster was successfully loaded into CYCU-3 MOF pores. The magnetic measurements indicated the preservation of SMMs insides MOF pores. The confinement of Mn 3 within CYCU-3 MOF pores significantly enhances its thermal stability whereas the overall framework stability remains unchanged. [Display omitted] • Mn 3 SMMs cluster was successfully loaded into CYCU-3 MOF pores. • The average 15 ​mol% insertion of Mn 3 SMMs is obviously higher than what was previously reported for SMM@silica composites. • The magnetic characteristics of Mn 3 SMM were preserved during their MOF incorporation processes. [ABSTRACT FROM AUTHOR]

• Favipiravir can significantly shorten SARS-CoV-2 RNA positive duration. • Favipiravir can increase negative conversion rate of virus in 30 days. • Favipiravir can improve the clinical symptoms of SARS-CoV-2 RNA recurrent positive. The clinical characteristics and treatment of patients who tested positive for COVID-19 after recovery remained elusive. Effective antiviral therapy is important for tackling these patients. We assessed the efficacy and safety of favipiravir for treating these patients. This is a multicenter, open-label, randomized controlled trial in SARS-CoV-2 RNA re-positive patients. Patients were randomly assigned in a 2:1 ratio to receive either favipiravir, in addition to standard care, or standard care alone. The primary outcome was time to achieve a consecutive twice (at intervals of more than 24 h) negative RT-PCR result for SARS-CoV-2 RNA in nasopharyngeal swab and sputum sample. Between March 27 and May 9, 2020, 55 patients underwent randomization; 36 were assigned to the favipiravir group and 19 were assigned to the control group. Favipiravir group had a significantly shorter time from start of study treatment to negative nasopharyngeal swab and sputum than control group (median 17 vs. 26 days); hazard ratio 2.1 (95% CI [1.1–4.0], p = 0.038). The proportion of virus shedding in favipiravir group was higher than control group (80.6% [29/36] vs. 52.6% [10/19], p = 0.030, respectively). C-reactive protein decreased significantly after treatment in the favipiravir group (p = 0.016). The adverse events were generally mild and self-limiting. Favipiravir was safe and superior to control in shortening the duration of viral shedding in SARS-CoV-2 RNA recurrent positive after discharge. However, a larger scale and randomized, double-blind, placebo-controlled trial is required to confirm our conclusion. [ABSTRACT FROM AUTHOR]