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Background: Astragalus membranaceus seeds have dormant properties that not only limit germination but also negatively affect the growth of seedlings. We investigated the enhancing effect of cold plasma treatment on seed germination and the positive effect on seedling growth of Astragalus membranaceus by treating its seeds with cold plasma at different power levels. Method: The Astragalus membranaceus seeds were treated with cold plasma at power levels of 40, 60, 80, 100, 120, 140, 160, 180, 200, 220 and 240 W for 15 seconds with helium gas and seeds without any treatment were used as control. Results: The Astragalus membranaceus seeds were treated with cold plasma, which not only improved seed germination, but also had a positive effect on seedling growth, with the best results for the 80 W power cold plasma treatment. The 80 W power cold plasma treatment increased the germination rate, germination index and vigor index of Astragalus membranaceus seeds by 26.8%, 12.4% and 39.8%, respectively; increased root length, CAT activity and SOD activity of Astragalus membranaceus seedlings by 24.5%, 99.7% and 7.1%, respectively and decreased the relative conductivity and MDA content of Astragalus membranaceus seedlings by 6.6% and 17.6%, respectively; compared with that of the control group.

Self-assembled nanostructures of amphiphilic peptides have a wide range of applications in bioimaging and delivery systems. In this study, we design and synthesize a biocompatible amphiphilic peptide (C-3) consisting of an RVRRFFF sequence and a nitrobenzoxadiazole fluorophore that can self-assemble into stable micelles for specifically detecting furin, a kind of proprotein convertase with promoting tumor progression. The self-assembly of C-3 with a β-sheet nanostructure is capable of a rapid and specific response to furin in only 5 min in aqueous solution because of the existence of the RVRR motif in the C-3 molecule. The C-3 nanostructures thus can selectively distinguish high furin-expressing cancer cells, like MDA-MB-231 cells, a kind of human breast cancer cells, from normal cells. Furthermore, the C-3 self-assembly can stay in living cells for a long time and are capable of durable detection of intracellular furin, being good for tracer analysis. To our knowledge, this is the first example of self-assembly of a soluble amphiphilic peptide that can selectively detect furin in high furin-expressing live cells.

Early detection of drug-induced acute kidney injury (AKI) is crucial for effective treatment and prevention of further injury. It remains challenging, however, because of the lack of activatable indicators with multimodality imaging capability that could increase the accuracy of diagnosis by mutual verification. Herein, we report an activatable probe, FDOCl-22, that enabled dual-modality detection of the early-stage drug-induced AKI. FDOCl-22 was completely soluble in water and highly sensitive to hypochlorous acid (HOCl). Dramatic increases of both near-infrared (NIR) emission and absorption were observed after reaction with HOCl. A correlation between HOCl concentration and drug-induced AKI was established using FDOCl-22 as a tool. As a consequence, the HOCl-activated probe was able to detect the early-stage drug-induced AKI by dual-modality imaging, irrespective of the drug stimulation time or dosage, by combining NIR fluorescence and photoacoustic imaging.

Detecting myeloperoxidase (MPO) activity in living organisms is important because MPO contributes to the pathogenesis of many diseases such as rheumatoid arthritis and other inflammatory diseases, artherosclerosis, neurodegenerative disease, and some cancers. However, rapid and effective methods for the detection of basal MPO activity in living systems have not yet been reported. Herein, we report a near-infrared (NIR) emissive "turn-on" probe FD-301 that can specifically bind to MPO and accurately measure MPO activity in living cells and in vivo via a rapid response to initial hypochlorous acid (HOCl), produced by MPO. Notably, FD-301 could detect the basal level of MPO activity in human promyelocytic leukemia cells (HL-60) and could discriminate between MPO high-expression and low-expression cells. Furthermore, FD-301 was successfully applied to in vivo imaging of MPO in MPO-dependent diseases, such as arthritis and inflammatory bowel disease.

We conducted a field investigation and controlled experiments in a glasshouse to determine how litter, seed position, and/or water supply affect seedling emergence and the establishment of two native grass species (Leymus chinensis (Trin.) Tzvel. and Bromus inermis Leyss) in northern China. Both water supply and seed position dramatically influenced seedling emergence and growth, as well as the accumulation of biomass for these two species. For L. chinensis, the quantity of litter had a significant impact on seedling survival, height increment, and biomass production when grown in either the glasshouse or the field while that component had little influence on B. inermis seedling emergence or survival. The effects of litter were physical but not biological or chemical, suggesting that this component is important only in the first year of seedling establishment. Therefore, longer-term experiments are probably necessary to examine the biological and chemical impacts that litter has on seedling performance.

It is important to detect hydrogen peroxide (H2O2) near mitochondrial DNA (mtDNA) because mtDNA is more prone to oxidative attack than nuclear DNA (nDNA). In this study, a mitochondria-targeted fluorescence probe, pep3-NP1, has been designed and synthesized. The probe contains a DNA-binding peptide, a H2O2 fluorescence reporter, and a positively charged red emissive styryl dye to facilitate accumulation in mitochondria. Due to groove binding of the peptide with DNA, the styryl dye of pep3-NP1 intercalated into the bases of DNA, leading to an increase in red fluorescence intensity (centered at 646 nm) and quantum yield. In this case, pep3-NP1 was a turn-on probe for labeling DNA. Subcellular locations of pep3-NP1 and MitoTracker suggested that pep3-NP1 mostly accumulated in the mitochondria of live cells. Namely, as an intracellular DNA marker, pep3-NP1 bound to mtDNA. In the presence of H2O2, pep3-NP1 emitted green fluorescence (centered at 555 nm). Thus, the ratio of green with red fluorescence of pep3-NP1 was suitable to reflect the change of the H2O2 level near mtDNA in living cells. The detecting limit for H2O2 was estimated at 2.9 and 5.0 μM in vitro and in cultured cells, respectively. The development of pep3-NP1 could help in studies to protect mtDNA from oxidative stress.

Background Plant breeding for resistance to agricultural pests is an essential element in the development of integrated crop management systems; however, the molecular and genetic mechanisms underlying resistance are poorly understood. In this pilot study, a transcriptomic analysis of a resistant (R) vs. a susceptible (S) variety of alfalfa, with (+T) or without (−T) thrips (= 4 treatments) was conducted, ‘GN-1’ (China) was defined as the resistant cultivar, and ‘WL323’ (America) was defined as the susceptible cultivar. Results A total of 970 mRNAs were differentially expressed, of which 129 up- and 191 down-regulated genes were identified in the R + T/R-T plants, while 413 up- and 237 down-regulated genes were identified in the S + T/S-T plants. KEGG analysis mapped 33 and 80 differentially expressed genes to 11 and 14 substantially enriched pathways for GN-1 and WL323, respectively. Five shared pathways were linked to plant resistance traits, including beta-Alanine metabolism, fatty acid degradation, chloroalkane and chloroalkene degradation, flavonoid biosynthesis, and phenylalanine metabolism. Conclusions Results indicated both thrips resistant and susceptible alfalfa cultivars can regulate gene expression in the salicylic acid (SA) and flavonoid biosynthesis pathways to induce defensive genes and protein expression (e.g. polyphenol oxidase, protease inhibitor), which enhances plant defence capacity. Electronic supplementary material The online version of this article (10.1186/s12864-018-4495-2) contains supplementary material, which is available to authorized users.

Alfalfa silage (Al) and corn silage (Cs) samples were collected from two large-scale farms in China; one of these farms used stack silos and the other used bunker silos for silage production. Three samples were collected from the upper and lower layers of each silo. Thus, six samples were examined for each of Al-stack, Al-bunker, Cs-stack, and Cs-bunker. Bacterial community was determined by denaturing gradient gel electrophoresis (DGGE). Lactic acid was the main fermentation product in Al-stack, Cs-stack and Cs-bunker, whereas acetic acid and butyric acid were predominant in Al-bunker. Pediococcus pentosaceus and Clostridium sp. were common to four silage types. Lactobacillus acetotolerans and Lactobacillus pontis were detected specifically in Cs, whereas the lactic acid bacteria identified in Al were regarded as those usually found in silage. Differences between stack and bunker silos were apparent in Al with regard to fermentation products and DGGE band patterns. Differences between the upper and lower layers were observed in the fermentation products in Cs regardless of silo type, whereas variations in the DGGE band patterns of Cs-stack were detected.

This study evaluated the effects of lactic acid bacteria inoculants on the fermentation quality and chemical composition of lucerne silage (A), a mixture of lucerne and wheat bran (A+WB), and a mixture of lucerne and corn husk (A+CH). The application rates of wheat bran in A+WB or corn husk in A+CH were 10%, 15%, and 20% of the whole fresh material. These different materials were treated with distilled water (Control), Lactobacillus plantarum 1 (LAB1), L. plantarum 2 (LAB2), L. plantarum 8 (LAB8) or a commercial inoculant (LALMAND) at a rate of 106 CFU/g of fresh forage. As the application rate of the by-products increased, the dry matter, lactate, propionate, and neutral detergent fibre (after heat-stable amylase treatment) contents increased, and the pH and the acetate, ammonia nitrogen, crude protein, and non-fibre carbohydrate contents decreased. The A+WB showed better fermentation quality than A and A+CH. The inoculants had beneficial effects on the silages, but the effects varied. The results indicate that the use of LAB1, LAB2, or LAB8 was better with A, whereas LALMAND was preferable for use with A+WB or A+CH. The saponin content decreased during ensiling and was positively correlated with the pH and the acetate and ammonia nitrogen content but negatively correlated with the dry matter content. The increase in the application rate of by-products and the addition of LALMAND further decreased the saponin content. Overall, the combined effects of the inoculants, by-products, and different application rates improved the fermentation quality and chemical composition and led to greater a reduction of saponin in lucerne silage, but the selection of suitable types and application rates of by-products and inoculants is essential.

Sheep play an important role in the nutrient cycling in extensively grazed grasslands, mainly through their annual return of around 5-25 kg N in the shape of urine. This return changes the temporal distribution of nutrients in soil and alters their bioavailability. Urine patches are the most important areas of the transformation and cycling of nutrients in the grazed grasslands. In order to make known the changes of soil chemical properties in sheep urine patches, an experiment was set up in the typical steppe area of central Inner Mongolia. The results indicated that soil pH value reached the maximum on the second day after urine excretion, and then declined. It maintained at around 6.5 from the 58th day, which was under the level of the control. Soil dissolved organic carbon (DOC) in urine patches exhibited the identical changing characteristics with soil pH, and had a significantly (P0.01) positive correlation with it. Soil total dissolved phosphorus (TDP) increased significantly (P0.05) after urine excretion, and reached the maximum at the 2nd day. The percentage of molybdate reactive phosphorus (MRP), dissolved organic phosphorus (DOP) and dissolved condensed phosphorus (DCP) showed significantly two changing phases, and there existed significantly (P0.05) negative correlations between MRP, DOP and DCP. Soil NH4+-N reached the maximum on the 2nd day after urine excretion and then declined, while soil NO3(-)-N increased significantly after 14 days and reached the maximum on the 21st day, showing significant "double peaks" characteristics. Soil dissolved organic nitrogen (DON) also increased significantly after urine excretion.

An experiment was installed in the typical steppe area of Central Inner Mongolia to study the distribution characteristics of lichen biomass in the restoration process. The experimental areas were continuously grazed for ten years (1989 to 1998) under different stocking rate, and stopped grazing since 1999. Two years (2001 to 2002) monitoring on the distribution of lichen biomass and its affecting factors showed that no significant difference was found between different stocking rate treatments (P0.05). There existed positive correlations between lichen biomass and plant species diversity and between soil water content and soil organic matter content (P0.05), and negative correlations between lichen biomass and soil bulk density, and between Gramineae plant functional group and plant community coverage and biomass (P0.05).