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In this study, we investigated the physiological and biochemical responses of Ulva species to variation in nutrient availability. Sampling was conducted at two sites on Jeju Island, Korea, namely, Handong, which is close to seven intensive land-based fish farms, and Hado, which has no apparent nearby nutrient sources. We examined the water column nutrient concentrations, nitrate reductase (NR) activity, nitrate uptake efficiency, tissue C, N, and P content, and stable isotope ratios of Ulva species. Water column NH4+, NO3− + NO2−, and PO43− concentrations were significantly higher at Handong than at Hado. NR activity and tissue N content of Ulva species were significantly higher at Handong than at Hado. Notably, nitrate uptake efficiency was inversely proportional to NR activity and tissue N content. The physiological and biochemical responses of Ulva species were closely related to dissolved inorganic nitrogen, which stimulates Ulva species to regulate growth. Additionally, the δ15N values of Ulva tissues at both sites were within the previously reported range for fresh groundwater. Therefore, the main nitrogen source for Ulva growth may be submerged groundwater with high nutrient concentrations. Our results provide invaluable information for estimating dissolved inorganic nitrogen levels in water, which may facilitate development of management policies. [ABSTRACT FROM AUTHOR]

Abstract Cell-penetrating peptides (CPPs) are short chains of amino acids that have shown remarkable potential to cross the cell membrane and deliver coupled therapeutic cargoes into cells. Designing and testing different CPPs to target specific cells or tissues is crucial to ensure high delivery efficiency and reduced toxicity. However, in vivo/in vitro testing of various CPPs can be both time-consuming and costly, which has led to interest in computational methodologies, such as Machine Learning (ML) approaches, as faster and cheaper methods for CPP design and uptake prediction. However, most ML models developed to date focus on classification rather than regression techniques, because of the lack of informative quantitative uptake values. To address these challenges, we developed POSEIDON, an open-access and up-to-date curated database that provides experimental quantitative uptake values for over 2,300 entries and physicochemical properties of 1,315 peptides. POSEIDON also offers physicochemical properties, such as cell line, cargo, and sequence, among others. By leveraging this database along with cell line genomic features, we processed a dataset of over 1,200 entries to develop an ML regression CPP uptake predictor. Our results demonstrated that POSEIDON accurately predicted peptide cell line uptake, achieving a Pearson correlation of 0.87, Spearman correlation of 0.88, and r2 score of 0.76, on an independent test set. With its comprehensive and novel dataset, along with its potent predictive capabilities, the POSEIDON database and its associated ML predictor signify a significant leap forward in CPP research and development. The POSEIDON database and ML Predictor are available for free and with a user-friendly interface at https://moreiralab.com/resources/poseidon/ , making them valuable resources for advancing research on CPP-related topics. Scientific Contribution Statement: Our research addresses the critical need for more efficient and cost-effective methodologies in Cell-Penetrating Peptide (CPP) research. We introduced POSEIDON, a comprehensive and freely accessible database that delivers quantitative uptake values for over 2,300 entries, along with detailed physicochemical profiles for 1,315 peptides. Recognizing the limitations of current Machine Learning (ML) models for CPP design, our work leveraged the rich dataset provided by POSEIDON to develop a highly accurate ML regression model for predicting CPP uptake. Graphical Abstract

Cell-penetrating peptides (CPPs) are short chains of amino acids that have shown remarkable potential to cross the cell membrane and deliver coupled therapeutic cargoes into cells. Designing and testing different CPPs to target specific cells or tissues is crucial to ensure high delivery efficiency and reduced toxicity. However, in vivo/in vitro testing of various CPPs can be both time-consuming and costly, which has led to interest in computational methodologies, such as Machine Learning (ML) approaches, as faster and cheaper methods for CPP design and uptake prediction. However, most ML models developed to date focus on classification rather than regression techniques, because of the lack of informative quantitative uptake values. To address these challenges, we developed POSEIDON, an open-access and up-to-date curated database that provides experimental quantitative uptake values for over 2,300 entries and physicochemical properties of 1,315 peptides. POSEIDON also offers physicochemical properties, such as cell line, cargo, and sequence, among others. By leveraging this database along with cell line genomic features, we processed a dataset of over 1,200 entries to develop an ML regression CPP uptake predictor. Our results demonstrated that POSEIDON accurately predicted peptide cell line uptake, achieving a Pearson correlation of 0.87, Spearman correlation of 0.88, and r2 score of 0.76, on an independent test set. With its comprehensive and novel dataset, along with its potent predictive capabilities, the POSEIDON database and its associated ML predictor signify a significant leap forward in CPP research and development. The POSEIDON database and ML Predictor are available for free and with a user-friendly interface at , making them valuable resources for advancing research on CPP-related topics. Scientific Contribution Statement: Our research addresses the critical need for more efficient and cost-effective methodologies in Cell-Penetrating Peptide (CPP) research. We introduced POSEIDON, a comprehensive and freely accessible database that delivers quantitative uptake values for over 2,300 entries, along with detailed physicochemical profiles for 1,315 peptides. Recognizing the limitations of current Machine Learning (ML) models for CPP design, our work leveraged the rich dataset provided by POSEIDON to develop a highly accurate ML regression model for predicting CPP uptake. [ABSTRACT FROM AUTHOR]

Recent discoveries show that fungi can take up environmental RNA, which can then silence fungal genes through environmental RNA interference. This discovery prompted the development of Spray-Induced Gene Silencing (SIGS) for plant disease management. In this study, we aimed to determine the efficacy of SIGS across a variety of eukaryotic microbes. We first examined the efficiency of RNA uptake in multiple pathogenic and non-pathogenic fungi, and an oomycete pathogen. We observed efficient double-stranded RNA (dsRNA) uptake in the fungal plant pathogens Botrytis cinerea, Sclerotinia sclerotiorum, Rhizoctonia solani, Aspergillus niger and Verticillium dahliae, but no uptake in Colletotrichum gloeosporioides, and weak uptake in a beneficial fungus, Trichoderma virens. For the oomycete plant pathogen, Phytophthora infestans, RNA uptake was limited and varied across different cell types and developmental stages. Topical application of dsRNA targeting virulence-related genes in pathogens with high RNA uptake efficiency significantly inhibited plant disease symptoms, whereas the application of dsRNA in pathogens with low RNA uptake efficiency did not suppress infection. Our results have revealed that dsRNA uptake efficiencies vary across eukaryotic microbe species and cell types. The success of SIGS for plant disease management can largely be determined by the pathogen's RNA uptake efficiency.

In this study, we investigated the physiological and biochemical responses of Ulva species to variation in nutrient availability. Sampling was conducted at two sites on Jeju Island, Korea, namely, Handong, which is close to seven intensive land-based fish farms, and Hado, which has no apparent nearby nutrient sources. We examined the water column nutrient concentrations, nitrate reductase (NR) activity, nitrate uptake efficiency, tissue C, N, and P content, and stable isotope ratios of Ulva species. Water column NH4+, NO3− + NO2−, and PO43− concentrations were significantly higher at Handong than at Hado. NR activity and tissue N content of Ulva species were significantly higher at Handong than at Hado. Notably, nitrate uptake efficiency was inversely proportional to NR activity and tissue N content. The physiological and biochemical responses of Ulva species were closely related to dissolved inorganic nitrogen, which stimulates Ulva species to regulate growth. Additionally, the δ15N values of Ulva tissues at both sites were within the previously reported range for fresh groundwater. Therefore, the main nitrogen source for Ulva growth may be submerged groundwater with high nutrient concentrations. Our results provide invaluable information for estimating dissolved inorganic nitrogen levels in water, which may facilitate development of management policies.

In the present investigation the adsorption behavior of methylene blue (MB) dye from aqueous solution onto untreated chinar leaves powder (CLP) and chinar leaves biochar (CLB) has been studied. To find out optimum conditions, adsorption process was carried out by varying different parameters such as contact time, adsorbent dose, concentration, temperature, salts, and pH. The equilibrium adsorption data were subjected to different popular isotherms (Langmuir, Freundlich, and Temkin) and kinetic models (pseudo-first order, pseudo-second order and intra-particle diffusion model). The thermodynamic study was also done on the adsorption process. The maximum monolayer adsorption capacities for MB dye onto given adsorbents are 1.53 mg/g (CLP) and 1.02 mg/g (CLB). Also the values of RL and n suggest favourable adsorption process of MB dye onto CLP and CLB adsorbents. The pseudo-second order kinetic model is best obeyed by both the mentioned adsorbents for MB dye adsorption with R2 value equal to 1. Thermodynamic study reveals that the adsorption process of MB dye is spontaneous, endothermic (CLB) and exothermic (CLP). At an equilibrium time of 20 min the uptake efficiency (> 99%) was recorded for both the low cost adsorbents (CLP and CLB) thus proved them fast and effective adsorbents for the removal of MB dye.

In the present investigation the adsorption behavior of methylene blue (MB) dye from aqueous solution onto untreated chinar leaves powder (CLP) and chinar leaves biochar (CLB) has been studied. To find out optimum conditions, adsorption process was carried out by varying different parameters such as contact time, adsorbent dose, concentration, temperature, salts, and pH. The equilibrium adsorption data were subjected to different popular isotherms (Langmuir, Freundlich, and Temkin) and kinetic models (pseudo-first order, pseudo-second order and intra-particle diffusion model). The thermodynamic study was also done on the adsorption process. The maximum monolayer adsorption capacities for MB dye onto given adsorbents are 1.53 mg/g (CLP) and 1.02 mg/g (CLB). Also the values of RL and n suggest favourable adsorption process of MB dye onto CLP and CLB adsorbents. The pseudo-second order kinetic model is best obeyed by both the mentioned adsorbents for MB dye adsorption with R² value equal to 1. Thermodynamic study reveals that the adsorption process of MB dye is spontaneous, endothermic (CLB) and exothermic (CLP). At an equilibrium time of 20 min the uptake efficiency (> 99%) was recorded for both the low cost adsorbents (CLP and CLB) thus proved them fast and effective adsorbents for the removal of MB dye. [ABSTRACT FROM AUTHOR]

Summary: Spray‐induced gene silencing (SIGS) is an innovative and eco‐friendly technology where topical application of pathogen gene‐targeting RNAs to plant material can enable disease control. SIGS applications remain limited because of the instability of RNA, which can be rapidly degraded when exposed to various environmental conditions. Inspired by the natural mechanism of cross‐kingdom RNAi through extracellular vesicle trafficking, we describe herein the use of artificial nanovesicles (AVs) for RNA encapsulation and control against the fungal pathogen, Botrytis cinerea. AVs were synthesized using three different cationic lipid formulations, DOTAP + PEG, DOTAP and DODMA, and examined for their ability to protect and deliver double stranded RNA (dsRNA). All three formulations enabled dsRNA delivery and uptake by B. cinerea. Further, encapsulating dsRNA in AVs provided strong protection from nuclease degradation and from removal by leaf washing. This improved stability led to prolonged RNAi‐mediated protection against B. cinerea both on pre‐ and post‐harvest plant material using AVs. Specifically, the AVs extended the protection duration conferred by dsRNA to 10 days on tomato and grape fruits and to 21 days on grape leaves. The results of this work demonstrate how AVs can be used as a new nanocarrier to overcome RNA instability in SIGS for crop protection. [ABSTRACT FROM AUTHOR]

To achieve the Paris climate target, deep emissions reductions have to be complemented with carbon dioxide removal (CDR). However, a portfolio of CDR options is necessary to reduce risks and potential negative side effects. Despite a large theoretical potential, ocean-based CDR such as ocean alkalinity enhancement (OAE) has been omitted in climate change mitigation scenarios so far. In this study, we provide a techno-economic assessment of large-scale OAE using hydrated lime (‘ocean liming’). We address key uncertainties that determine the overall cost of ocean liming (OL) such as the CO2 uptake efficiency per unit of material, distribution strategies avoiding carbonate precipitation which would compromise efficiency, and technology availability (e.g., solar calciners). We find that at economic costs of 130–295 $/tCO2 net-removed, ocean liming could be a competitive CDR option which could make a significant contribution towards the Paris climate target. As the techno-economic assessment identified no showstoppers, we argue for more research on ecosystem impacts, governance, monitoring, reporting, and verification, and technology development and assessment to determine whether ocean liming and other OAE should be considered as part of a broader CDR portfolio.

Background: Silicon (Si) is a multiple stress attenuator element in plants, however more research is needed to elucidate the actions in the plants defense system with low nutrition of manganese (Mn) for a prolonged period, and the attenuation mechanisms involved in the effects of Mn deficiency on energy cane with high fiber content. Thus, the objective of this study was to evaluate whether Si reduces the oxidative stress of the energy cane grown in low Mn in nutrient solution, to mitigate the effects of Mn deficiency, improving enzymatic and non-enzymatic defense, uptake of Mn the plant growth. Methods: An experiment was carried out with pre-sprouted seedlings of Saccharum spontaneum L. in a 2 × 2 factorial scheme in five replications in which the plants were grown under sufficiency (20.5 μmol L−1) and deficiency (0.1 μmol L−1) of Mn combined with the absence and presence of Si (2.0 mmol L−1) for 160 days from the application of the treatments. The following parameters were evaluated: accumulation of Mn and Si, H2O2, MDA, activity of SOD and GPOX, total phenol content, pigments, and quantum efficiency of PSII. Results: Mn deficiency induced the oxidative stress for increase the H2O2 and MDA content in leaves of plants and reduce the activity of antioxidant enzymes and total phenols causing damage to quantum efficiency of photosystem II and pigment content. Si attenuated the effects of Mn deficiency even for a longer period of stress by reducing H2O2 (18%) and MDA (32%) content, and increased the Mn uptake efficiency (53%), SOD activity (23%), GPOX (76%), phenol contents, thus improving growth. Conclusions: The supply of Si promoted great nutritional and physiological improvements in energy cane with high fiber content in Mn deficiency. The results of this study propose the supply of Si via fertirrigation as a new sustainable strategy for energy cane cultivation in low Mn environments. [ABSTRACT FROM AUTHOR]

Continuous nitrogen (N) deposition has raised concerns that temperate forest ecosystems shift from N limitation to progressing phosphorus (P) limitation under global change. According to the multiple resource limitation theory, this will not only influence P economy, but also reduce N uptake and use efficiencies of trees such that growth is equally limited by N and P. We used different global change scenarios including summer drought to test the prediction of this hypothesis for the N economy of European beech (Fagus sylvatica L.) saplings. Our study demonstrates that the N uptake efficiency (NUptakeE) of beech adjusts to soil N availability and stabilizes leaf and fine root N concentrations. By contrast, both efficiencies of N use were curtailed by increasing P limitation under elevated soil N. The photosynthetic N use efficiency (PNUE) was serially reduced with decreasing soil P availability and increasing foliar N:P ratios, while the N use efficiency (NUE) decreased with increasing fine root N:P ratios. Soil drought induced relative P deficiency alike and reduced NUptakeE, PNUE, and NUE independent from the soil N:P ratios. We conclude that not only N deposition but also increasing summer droughts might affect N:P ratios, thereby inducing P imbalances and affecting the N economy of European beech saplings under global change.

Establishment of nutrient management of citrus groves for high yield and superior crop quality is a need for efficient production. Limited phosphorus (P) availability of low fertility tropical soils in Brazil impairs citrus production since adequate P supply is important in the first years after field planting. Research has demonstrated that tree growth and fruit yield in response to P fertilization vary depending on rootstock varieties. Therefore, this study evaluated P uptake and redistribution by Pêra sweet orange on Rangpur lime or Cleopatra mandarin rootstocks initially grown in nutrient solution containing either deficient (0.005 mmol/L) or suficient(1.0 mmol/L) P levels. Each of these groups of plants was later half maintained in the deficient P whereas other half was changed to the suficient P solutions both labeled with 32P (14.8 MBq per 9.0 L pot). Plants were further grown for 50 days. Based on concentrations of P in plant parts derived from solution and P remobilized in plant, we observed that, despite variations on plant growth on different rootstocks, P taken up by those on Rangpur lime was superior confirming greater efficiency of nutrient uptake of this rootstock under a non mycorrhized condition. Estimates of P remobilized from plant reserve to young leaves suggested that the process was more marked for plants on Cleopatra mandarin irrespective to P treatments. These explained the fact that leaf visual symptoms of P deficiency are more frequent on trees on Cleopatra rootstock and presented the need to fine tune P fertilization recommendations.

Abstract Ulva ohnoi is a green macroalga with fast growth and high rates of nitrogen and phosphorus absorption. Recently, this species has been recorded in several places with record green tide formation in some of them. Using molecular tools, we herein report the first occurrence of this species in Brazil and demonstrate its potential for phytoremediation in typical environmental concentrations of Cd (0.625–15 µg L-1). Similarly, the effects of physicochemical parameters (salinity and temperature) on the toxicity and uptake efficiency of this species were evaluated. Molecular analysis of two sequences (1141 bp) obtained corroborates another 34 sequences for U. ohnoi obtained from GenBank. The addition of Cd in the medium affected photosynthetic parameters and reduced growth rate. U. ohnoi showed resistance to Cd when cultivated at 18 °C, S15 and 18–25 °C, S35, at concentrations between 0.625 and 2.5 μg. L-1 of Cd; yet, positive growth rate was maintained. Dose-dependent accumulation was observed in all combinations of factors used with a maximum value of 4.20 μg Cd per gram of dry seaweed at 15 μg. L-1 of Cd at 18 °C and S35. Maximum value of the concentration factor was 81.3 ± 1.1% of Cd added at the concentration of 0.625 μg. L-1 to S15 and 18 °C. Our results demonstrate the potential of using U. ohnoi in the phytoremediation of Cd in saltwater or brackish water. Highlights • Ulva ohnoi removes 81.3% of the Cd added. • Dose-dependent accumulation was observed in all factors and combinations used. • Positive GRs were observed at the lowest concentrations of Cd used. • Changes in parameters analyzed were observed at all concentrations of Cd used. [ABSTRACT FROM AUTHOR]

While a severe decrease in phosphorus (P) availability is already taking place in a large number of ecosystems, drought and nitrogen (N) deposition will likely further decrease the availability of P under global change. Plants have developed physiological strategies to cope with decreasing P resources, but it is unclear how these strategies respond to elevated N deposition and summer droughts. We investigated the influence of N and P availability and soil drought on P uptake (H333PO4 feeding experiment) and use efficiencies in young Quercus calliprinos Webb. trees. We hypothesized that (H1) the expected increases in soil N:P ratios will increase the efficiencies of P uptake and use of oak saplings but will decrease the efficiencies of N uptake and use, whereas (H2) drought will affect P uptake efficiency more than N uptake efficiency. In confirmation of (H1) we found that a sharp increase of the soil N:P ratio from 4 to 42 g g-1 significantly increased the instantaneous 33P uptake efficiency (33PUptakeE) by five-fold and long-term P uptake efficiency (PUptakeE) by six-fold, while it decreased N uptake efficiency (NUptakeE) and N use efficiency (NUE). In contradiction to (H1), P use efficiency (PUE) did not respond to the simulated extended gradient of soil N:P ratios but remained relatively constant. (H2) was only partially confirmed as soil drought reduced PUptakeE by up to a fourth at high soil N:P ratios but had no significant effect on NUptakeE. As a consequence, increasing summer droughts may decrease the response of PUptakeE to increasing P limitation, which – in the absence of adjustments of the efficiency of P use – can aggravate growth reductions in this eastern Mediterranean tree species under global change. [ABSTRACT FROM AUTHOR]

Background: Cancer is the leading cause of death in human disease and is a major public health problem around the world. Exosomes are a promising cancer biomarker and therapy target. Recent evidence demonstrate that tumor cells could inhibit natural killer (NK) cells’ immune surveillance function by releasing exosomes into tumor microenvironment. The intercelluar uptake of tumor cell-derived exosomes by NK cells is vital for using these exosomes in tumor diagnose and therapy. We aimed to investigate the efficiency of NK cell uptake of tumor exosomes. Methods: Exosomes derived from different tumor cells, RAW264.7 cells and NK cells were labeled by fluorescent dye and co-cultured with NK cells. The uptake rates of NK cells were observed by fluorescence microscope and analyzed by flow cytometry. Results: NK cells could take up more exosomes from themselves and cell lines originating from bone marrow. Epithelial cell lines can take up more exosomes from epithelial cells. There was no significant difference in uptake efficiency between Jurkat cells and RAW264.7 cells by NK cells, indicating that maybe the origin other than species affects the efficiency of recipient cell uptake of exosomes. Different tumor cells derived exosomes had different uptake efficiency by NK cells. Conclusion: There is certain pattern of NK cells uptake tumor exosomes, which provide important insights on how tumors affect NK cells and develop appropriate countermeasures. In addition, it can be also helpful to select and design proper exosomes as a drug carrier in future.

Embora não seja considerado nutriente essencial às plantas, o Si é classificado como elemento benéfico ou útil, mas pode alterar a dinâmica nutricional das plantas. Objetivando comparar a eficiência nutricional de variedades de cafeeiro (Catuaí, Mundo Novo e Icatu) em resposta à adubação silicatada, realizou-se um experimento em blocos casualizados, com as três variedades de mudas em tubetes combinadas com seis doses de CaSiO3 (T0 = 0, T1 = 0,063, T2 = 0,125, T3 = 0,25, T4 = 0,5 e T5 = 1,0 g dm-3 de substrato). A variedade Icatu teve a maior eficiência de absorção (EA) de Cu, Zn, Fe e Si, maior eficiência de uso (EU) de N, K, Ca, B e Mn, não diferindo da Mundo Novo com relação aos nutrientes N, Ca e Mn, e maior eficiência de translocação (ET) de N, S, Zn e de Fe. A Catuaí teve maior EA de P, K, B e Mn, não diferindo da Mundo Novo com relação aos nutrientes P, K e Mn, maior EU para Mg, S, Cu, Zn, Fe e Si, provavelmente devido à melhor ET desses nutrientes, exceto para Fe e Si. A Mundo Novo foi mais eficiente na absorção de N, K, Ca, Mg, Mn e Si, teve maior EU de P e Mn e maior ET de K, Ca, B, Mn e Si.Silicon is classified as a beneficial nutrient and can improve the nutritional dynamics of plants, although it is not considered an essential nutrient for plants. In an experiment in a randomized block design, three coffee cultivars (Catuaí, Mundo Novo and Icatu) were planted in plastic tubes, combined with six doses of calcium silicate (T0=0, T1=0.063, T2=0.125, T3=0.25, T4=0.5 and T5=1.0 g dm-3 substrate), to compare the nutritional efficiency of the cultivars in response to silicon fertilization. Cultivar Icatu showed the higher uptake efficiency (UE) of Cu, Zn, Fe, and Si, and efficiency of use (EU) of N, K, Ca, B, and Mn, but the later did not differ from Mundo Novo cultivar (N, Ca, and Mn). The efficiency of translocation (ET) was higher for N, S, Zn, and Fe. For Catuaí the uptake efficiency of P, K, B, and Mn was higher, but did not differ from Mundo Novo for P, K, and Mn. The Catuai's s efficiency of use for Mg, S, Cu, Zn, Fe, and Si was higher, probably because of a better ET of these nutrients, with exception of Fe and Si. The cultivar Mundo Novo was the most efficient in N, K, Ca, Mg, Mn and Si uptake, had the higher EU of P and Mn, and the highest ET of K, Ca, B, Mn, and Si.

This study investigated how spring nitrogen (N) application affects N uptake and growth performance in tall bearded (TB) iris 'Immortality' (Iris germanica L.). Container-grown iris plants were treated with 0, 5, 10, 15, or 20 mm N from 15NH415NO3 through fertigation using a modified Hoagland's solution twice a week for 6 weeks in Spring 2013. Increasing N rate increased plant height, total plant dry weight (DW), and N content. Total N content was closely related to total plant DW. The allocation of N to different tissues followed a similar trend as the allocation of DW. In leaves, roots, and rhizomes, increasing N rate increased N uptake and decreased carbon (C) to N ratio (C/N ratio). Leaves were the major sink for N derived from fertilizer (NDFF). As N supply increased, DW accumulation in leaves increased, whereas DW accumulation in roots and rhizomes was unchanged. This indicates increasing N rate contributed more to leaf growth in spring. Nitrogen uptake efficiency (NupE) had a quadratic relationship with increasing N rate and was highest in the 10 mm N treatment, which indicates 10 mm was the optimal N rate for improving NupE in this study. [ABSTRACT FROM AUTHOR]

Cell penetrating peptides (CPPs) were developed as vehicles for efficient delivery of various molecules. An ideal CPP‐peptide should not display any toxicity against cancer cells as well as healthy cells and efficiently enter into the cell. Because of the cationic nature and the intrinsic vector capabilities, these peptides can cause cytotoxicity. One of the possible reasons for toxicity of CPPs is direct translocation and consequently, pore formation on the plasma membrane. In this study it was demonstrated that interaction of poly‐glutamate with CPP considerably reduced their cytotoxicity in A549 cell. This strategy could be useful for efficient drug delivery mediated by CPP. [ABSTRACT FROM AUTHOR]

Spray-Induced Gene Silencing (SIGS) is an innovative and eco-friendly technology where topical application of pathogen gene-targeting RNAs to plant material can enable disease control. SIGS applications remain limited because of the instability of dsRNA, which can be rapidly degraded when exposed to various environmental conditions. Inspired by the natural mechanism of cross-kingdom RNAi through extracellular vesicle trafficking, we describe herein the use of artificial nanovesicles (AVs) for dsRNA encapsulation and control against the fungal pathogen, Botrytis cinerea . AVs were synthesized using three different cationic lipid formulations, DOTAP + PEG, DOTAP, and DODMA, and examined for their ability to protect and deliver dsRNA. All three formulations enabled dsRNA delivery and uptake by B. cinerea . Further, encapsulating dsRNA in AVs provided strong protection from nuclease degradation and from removal by leaf washing. This improved stability led to prolonged RNAi-mediated protection against B. cinerea both on pre- and post-harvest plant material using AVs. Specifically, the AVs extended the protection duration conferred by dsRNA to 10 days on tomato and grape fruits and to 21 days on grape leaves. The results of this work demonstrate how AVs can be used as a new nanocarrier to overcome dsRNA instability in SIGS for crop protection., Competing Interests: Conflict of interests The authors declare that they have no competing interests.

Background and aims: Phosphorus (P) is a mobile nutrient in the plant so growth depends on its internal remobilization and a plant's ability to respond to its availability in the growing media. This study was conducted to evaluate the influence of P status and rootstocks on the patterns of P uptake and remobilization in orange trees. Methods: Sweet orange trees on Cleopatra mandarin (CM) or Rangpur lime (RL) rootstocks were grown for nine months in nutrient solution (NS) that was either P-deficient (DNS) or was P-sufficient (SNS). After this period, half of the trees were reciprocally transferred between DNS and SNS (from D to S and S to D), while the others remained in their initial P availability. Results: Trees on RL had more shoot and root growth, accumulated more P and had greater efficiency of P absorption and transport to the shoot (PAE) than those on CM. The major source of P for growth was previously stored P even with an adequate current P supply to the roots. This suggested the dominance of P remobilization over P uptake and the requirement that trees had sufficient stored P to meet P demand of new growth. Trees on CM had greater concentrations of remobilized P in new shoots than trees on RL. Conclusion: Trees grafted on rootstocks less able to take up P (CM) were more dependent on the internal reserves of P for new growth than rootstocks with higher PAE (RL). [ABSTRACT FROM AUTHOR]

Background: Cancer is the leading cause of death in human disease and is a major public health problem around the world. Exosomes are a promising cancer biomarker and therapy target. Recent evidence demonstrate that tumor cells could inhibit natural killer (NK) cells' immune surveillance function by releasing exosomes into tumor microenvironment. The intercelluar uptake of tumor cell-derived exosomes by NK cells is vital for using these exosomes in tumor diagnose and therapy. We aimed to investigate the efficiency of NK cell uptake of tumor exosomes., Methods: Exosomes derived from different tumor cells, RAW264.7 cells and NK cells were labeled by fluorescent dye and co-cultured with NK cells. The uptake rates of NK cells were observed by fluorescence microscope and analyzed by flow cytometry., Results: NK cells could take up more exosomes from themselves and cell lines originating from bone marrow. Epithelial cell lines can take up more exosomes from epithelial cells. There was no significant difference in uptake efficiency between Jurkat cells and RAW264.7 cells by NK cells, indicating that maybe the origin other than species affects the efficiency of recipient cell uptake of exosomes. Different tumor cells derived exosomes had different uptake efficiency by NK cells., Conclusion: There is certain pattern of NK cells uptake tumor exosomes, which provide important insights on how tumors affect NK cells and develop appropriate countermeasures. In addition, it can be also helpful to select and design proper exosomes as a drug carrier in future., Competing Interests: Conflict of interest The authors declare no conflict of interest.

Traumatic spinal cord injury leads to neuronal damage and results in varying levels of functional impairment. Nanomaterial-based drug delivery systems provide potential for axon regeneration from specific neurons by crossing blood-brain barrier. In our work, we analyzed whether magnetic nanoparticles (MNPs) detrimentally affect outgrowth processes in primary dorsal root ganglion (DRG) neurons from embryonic chick. The DRG neurons were extracted from E9-12 chick embryos and dissociated. The dissociated DRG was treated with different concentrations of MNPs for 72 hours. Images were obtained and analyzed using a Nikon A1 confocal microscope system. Our study showed that the highest dose of MNPs applied was minimally toxic for DRG cells treated for 72 hours. We found that 72 hours of MNP treatment did not affect the number of neurites, branches and neurite length in DRG cells. We did not see any effect on the morphology of neurons after MNP treatment. Also, we used rat primary neurons to study the uptake efficiency of surface functionalized nanoparticles (SFNPs) by different cell types in mixed cortical culture. Primary rat cortical cells were extracted from P0-P2 rats and cultured on PDL coated plates. The cultured cells were treated with -NH2 and -COOH surface functionalized nanocarriers for 30 mins. After immunocytochemistry, images were obtained using a Nikon A1 confocal microscopy and analyzed. Uptake of a portion of our nanoparticles was seen in cortical neurons. Together, these results show the feasibility of nanocarriers for targeted drug delivery to encourage axon regeneration following nervous system damage. [ABSTRACT FROM AUTHOR]