OTULIN allies with LUBAC to govern angiogenesis by editing ALK1 linear polyubiquitin.

OTULIN coordinates with LUBAC to edit linear polyubiquitin chains in embryonic development, autoimmunity, and inflammatory diseases. However, the mechanism by which angiogenesis, especially that of endothelial cells (ECs), is regulated by linear ubiquitination remains unclear. Here, we reveal that constitutive or EC-specific deletion of Otulin resulted in arteriovenous malformations and embryonic lethality. LUBAC conjugates linear ubiquitin chains onto Activin receptor-like kinase 1 (ALK1), which is responsible for angiogenesis defects, inhibiting ALK1 enzyme activity and Smad1/5 activation. Conversely, OTULIN deubiquitinates ALK1 to promote Smad1/5 activation. Consistently, embryonic survival of Otulin-deficient mice was prolonged by BMP9 pretreatment or EC-specific ALK1Q200D (constitutively active) knockin. Moreover, mutant ALK1 from type 2 hereditary hemorrhagic telangiectasia (HHT2) patients exhibited excessive linear ubiquitination and increased HOIP binding. As such, a HOIP inhibitor restricted the excessive angiogenesis of ECs derived from ALK1G309S-expressing HHT2 patients. These results show that OTULIN and LUBAC govern ALK1 activity to balance EC angiogenesis.

Visualization of the Infection and Colonization Process of Dendrobium officinale Using a Green Fluorescent Protein-Tagged Isolate of Fusarium oxysporum.

Dendrobium officinale soft rot is a widespread and destructive disease caused by Fusarium oxysporum that can seriously affect its yield and quality. To better understand the fungal infection and colonization, we successfully created an F. oxysporum labeled with green fluorescent protein (GFP) using Agrobacterium tumefaciens-mediated transformation (ATMT) method. Transformants had varying fluorescence intensities, but their pathogenicity did not differ from that of the wild type (WT). Fluorescence microscopy revealed that F. oxysporum primarily entered the aboveground portion of D. officinale through the leaf margin, stomata, or by direct penetration of leaf surface. It then colonized the mesophyll and spreads along its vascular bundles. After 14 d of culture, D. officinale exhibited typical symptoms of decay and wilting, accompanied by a pronounced fluorescence signal in the affected area. The initial colonization of F. oxysporum in the subterranean region primarily involved attachment to the root hair and epidermis, which progressed to the medullary vascular bundle. At 14 days post inoculation (dpi), the root vascular bundles of D. officinale exhibited significant colonization by F. oxysporum. Macroconidia were also observed in black rot D. officinale tissue. In particular, the entire root was surrounded by a significant number of chlamydospore-producing F. oxysporum mycelia at 28 dpi. This approach allowed the visualization of the complete infection process of F. oxysporum and provided a theoretical foundation for the development of field control strategies.

Molecular mechanism of Osthole against chitin synthesis of Ustilaginoidea virens based on combined transcriptome and metabolome analyses.

Rice false smut, caused by the fungus Ustilaginoidea virens, is a destructive grain disease in rice-producing areas worldwide. To reveal the action mechanism of osthole against U. virens, the mycelial morphology, differential genes and metabolites of osthole-treated U. virens were determined using electron microscopy and multi-omics, respectively. The hyphae of osthole-treated U. virens were severely wrinkled and distorted with rough cell walls, uneven thickness, and protoplast aggregation. Calcium fluorescent white staining showed that osthole affected chitin synthesis in U. virens. The differential genes and metabolites in U. virens were significantly enriched in amino sugar and nucleotide sugar metabolism pathway. The expression of the acetylglucosamine phosphate mutase (AGM) gene (UvAGM1) and UDP-N-acetylglucosamine was significantly down regulated. The AGM of osthole-treated U. virens was 133.43 ng/mL, which was significantly lower than that of the control group (205.67 ng/mL). Osthole combined with the amino acid residue THR334 of AGM via hydrogen bonding. These results indicate that UvAGM1 may be a key candidate gene of osthole against U. virens. Overall, the results provide valuable information for the application of osthole to control rice false smut.

Overexpression of NADPH-cytochrome P450 reductase is associated with sulfoxaflor resistance and neonicotinoid cross-resistance in Nilaparvata lugens (Stål).

Nicotinamide adenine dinucleotide phosphate (NADPH)-cytochrome P450 reductase (CPR), a crucial electron-transfer partner of P450 systems, is required for various biological reactions catalyzed by P450 monooxygenase. Our previous study indicated that enhanced P450 enzyme detoxification and CYP6ER1 overexpression contributed to sulfoxaflor resistance in Nilaparvata lugens. However, the association between CPR, sulfoxaflor resistance, and neonicotinoid cross-resistance in N. lugens remains unclear. In this study, the sulfoxaflor-resistant (SFX-SEL) (RR = 254.04-fold), resistance-decline (DESEL) (RR = 18.99-fold), and susceptible unselected (UNSEL) strains of N. lugens with the same genetic background were established. Real-time quantitative polymerase chain reaction (RT-qPCR) revealed that the N. lugens CPR (NlCPR) expression level in the SFX-SEL strain was 6.85-fold and 6.07-fold higher than in UNSEL and DESEL strains, respectively. NlCPR expression was significantly higher in the abdomens of UNSEL, DESEL, and SFX-SEL fourth-instar nymphs than in other tissues (thoraxes, heads, and legs). Additionally, sulfoxaflor stress significantly increased NlCPR mRNA levels in the UNSEL, SFX-SEL and DESEL strains. NlCPR silencing by RNA interference (RNAi) dramatically increased the susceptibility of the UNSEL, DESEL, and SFX-SEL strains to sulfoxaflor, but the recovery of SFX-SEL was more obvious. Furthermore, NlCPR silencing led to a significant recovery in susceptibility to nitenpyram, dinotefuran, clothianidin, and thiamethoxam across all strains (UNSEL, DESEL, and SFX-SEL), with the greatest degree of recovery in the sulfoxaflor-resistant strain (SFX-SEL). Our findings suggest that NlCPR overexpression contributes to sulfoxaflor resistance and neonicotinoid cross-resistance in N. lugens. This will aid in elucidating the significance of CPR in the evolution of P450-mediated metabolic resistance in N. lugens.

Natural product osthole can significantly disrupt cell wall integrity and dynamic balance of Fusarium oxysporum.

Dendrobium officinale Kimura et Migo is a traditional Chinese herbal medicinal plant. However, the frequent occurrence of soft rot disease (SRD) is one of the most harmful diseases in D. officinale production in recent years, which can seriously affect its yield and quality. In this study, the major pathogenic fungus (SR-1) was isolated from D. officinale with typical symptoms of SRD, and was identified as Fusarium oxysporum through morphological and molecular identification. The biological activities of five natural products were determined against F. oxysporum using a mycelial growth inhibition assay. The results showed that osthole had the highest antifungal activity against F. oxysporum, with an EC50 value of 6.40 mg/L. Scanning electron microscopy (SEM) showed that osthole caused F. oxysporum mycelia to shrink and deform. Transmission electron microscopy (TEM) showed that the organelles were blurred and the cell wall was thickened in the presence of osthole. The sensitivity of F. oxysporum to calcofluor white (CFW) staining was significantly enhanced by osthole. Relative conductivity measurements and propidium iodide (PI) observation revealed that osthole had no significant effect on the cell membrane. Further experiments showed that the activity of chitinase and ß-1,3-glucanase were decreased, and expression levels of chitinase and ß-1,3-glucanase related genes were significantly down-regulated after treatment with osthole. In conclusion, osthole disrupted the cell wall integrity and dynamic balance of F. oxysporum, thereby inhibiting normal mycelial growth.

Improving the biocompatibility and antibacterial efficacy of silver nanoparticles functionalized with (LLRR)3 antimicrobial peptide.

The selection of effective antibiotics is becoming increasingly limited due to the emergence of bacterial resistance. Designing and developing nanoscale antibacterials is a strategy for effectively addressing the antibiotic crisis. In this work, AgNPs@AMP nanoparticles were synthesized to take advantage of the synergistic antibacterial activity of the (LLRR)3 antimicrobial peptide (AMP) and silver nanoparticles (AgNPs). Based on morphological structure characterization and biocompatibility analysis, the inhibitory properties of AgNPs@AMP on Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were evaluated. The results demonstrated that AMP and AgNPs were physically bound to form AgNPs@AMP nanoparticles, which had better solution stability, improved nanomaterial properties, and overcame the hemolytic activity of AMP and the cytotoxicity of AgNPs. The inhibitory activity of AgNPs@AMP against E. coli and S. aureus was significantly higher than that of AMP and AgNPs. It was capable of disrupting the morphology and internal structure of cells, damaging the cell membrane, and inhibiting the activity of enzymes related to the material-energy metabolism of the tricarboxylic acid cycle. Compared to AMP and AgNPs, AgNPs@AMP were found to effectively inhibit the infection of mouse wounds and promote their healing. Therefore, AMP-modified AgNPs can enhance their biocompatibility and antibacterial activity, and they can be further developed as a potential antimicrobial agent.

Generation of an Ihh-mKate2-Dre knock-in mouse line.

Indian hedgehog (Ihh), a member of the Hh family, plays important roles in vertebrate development and homeostasis. To improve our understanding of the function of Ihh-expressing cells and their progeny as well, we generate an Ihh-mKate2tomm20 -Dre knock-in mouse line that can label Ihh-positive cells with a fluorescence protein mKate2 and trace Ihh-positive cells and their progeny via Dre-mediated recombination. Consistent with previous reports, we verified Ihh expression in hypertrophic chondrocytes of growth plate and granulosa cells of ovarian follicles by mKate2 immunostaining, and meanwhile confirmed Dre activity in these cells via a Dre reporter mouse line Rosa26-confetti2. We also found, for the first time, that Ihh can mark some cell types, including retinal ganglion cells, Purkinje cells, and gallbladder epithelial cells. Taken together, the Ihh-mKate2tomm20 -Dre mouse is a genetic tool for examining the precise expression profile of Ihh and tracing Ihh-expressing cells and their progeny.

Identification and genome analysis of a tomato zonate spot virus isolate from Bidens pilosa.

Bidens pilosa is a weed species that invades crop areas in tropical and subtropical regions. To date, only two potyviruses have been reported to infect B. pilosa. Here, we report the complete genome sequence of a tomato zonate spot tospovirus (TZSV) isolate from Bidens named TZSV-Bidens. The tripartite RNA of the TZSV-Bidens genome contains L, M, and S segments that are 8912, 4724, and 2997 nt in length, respectively. The genome contains five open reading frames (ORFs), with 92.23-95.01% amino acid sequence identity to the TZSV-YN isolate. Phylogenetic analysis based on amino acid sequences of members of the family Tospoviridae showed that TZSV-Bidens was grouped into a well-supported Eurasian cluster. The intergenic regions (IGRs) of the M and S RNAs are among the most variable regions and are far shorter than those of the TZSV-YN reference genome.

Establishment of an Artificial Inoculation Method of Ustilaginoidea virens Without Damaging the Rice Panicle Sheaths.

Rice false smut (RFS) is a destructive disease of rice worldwide caused by Ustilaginoidea virens. Nevertheless, there is a lack of efficient and stable artificial inoculation method to simulate the natural infection of U. virens, which is an important factor limiting further research on the pathogen. The purpose of this study was to establish an artificial inoculation method, which can simulate the natural infection process of U. virens without destroying the panicle sheath structure of rice. In this research, rice plants were inoculated by soaking roots at the seedling stage, spraying at the tillering stage, injecting at the booting stage, and again spraying at the flowering stage to determine the appropriate artificial inoculation time. Meanwhile, the panicle sheath instillation method and the injection inoculation method were compared. The results show that stages 6 to 8 of young panicle differentiation are an important period for U. virens infection. There were no significant differences in the mean rates of infected panicles, mean rates of infected grains, and maximum infected grains per panicle between the two inoculation methods. However, the frequency of RFS ball occurrence at the upper part of the panicles was significantly higher on the spikelets inoculated by the injection method than that of spikelets inoculated by natural infection and panicle sheath instillation. Therefore, panicle sheath instillation method was more similar to the natural infection of U. virens in the field. This research exhibited an innovative artificial inoculation method for identification of U. virens pathogenicity and evaluation of rice resistance against RFS.

Repellency Mechanism of Natural Guar Gum-Based Film Incorporated with Citral against Brown Planthopper, Nilaparvata lugens (Stål) (Hemiptera: Delphacidae).

Using of plant essential oil that coevolved as a defense mechanism against agriculture insects is an alternative means of controlling many insect pests. In order to repel brown planthoppers (BPHs), the most notorious rice insect pest, a new film based on guar gum incorporated with citral (GC film) was formulated, which was effective while being environmentally friendly. In this paper, the effect and mechanism of GC film repellency against BPHs were determined. Repellent activity test and olfactory reaction analysis showed that GC film had repellency effect against BPHs, with repellency of 60.00% and 73.93%, respectively. The result of olfactory reaction indicated that GC film repellency against BPHs relied on smell. EPG analysis showed the proportion and mean duration of np waveform were significantly higher than in CK and increased following the treatment concentration, which indicated that GC film affected the recognition of BPHs to rice. Further analysis by RNA sequencing analysis showed a total of 679 genes were significantly upregulated and 284 genes were significantly downregulated in the BPHs fed on the rice sprayed with GC film compared to control. Odorant-binding protein (OBP) gene 797 and gustatory receptor gene (GR)/odorant receptor (OR) gene 13110 showed a significant decrease in differential expression and significant increase in differential expression, respectively. There were 0.66 and 2.55 differential expression multiples between treated BPHs and control, respectively. According to the results described above, we reasoned that GC film repellency against BPHs due to smell, by release of citral, caused the recognition difficulties for BPHs to rice, and OBP gene 797 and GR/OR gene 13110 appeared to be the crucial candidate genes for GC film repellency against BPHs. The present study depicted a clear and consistent repellency effect for GC film against BPHs and preliminarily clarified the mechanism of GC film as a repellent against BPHs, which might offer an alternative approach for control of BPHs in the near future. Our results could also help in the development and improvement of GC films.

The Cross-Resistance Pattern and the Metabolic Resistance Mechanism of Acetamiprid in the Brown Planthopper, Nilaparvata lugens (Stål).

Acetamiprid is widely used in paddy fields for controlling Nilaparvata lugens (Stål). However, the risk of resistance development, the cross-resistance pattern and the resistance mechanism of acetamiprid in this pest remain unclear. In this study, an acetamiprid-resistant strain (AC-R) was originated from a field strain (UNSEL) through successive selection with acetamiprid for 30 generations, which reached 60.0-fold resistance when compared with a laboratory susceptible strain (AC-S). The AC-R strain (G30) exhibited cross-resistance to thiamethoxam (25.6-fold), nitenpyram (21.4-fold), imidacloprid (14.6-fold), cycloxaprid (11.8-fold), dinotefuran (8.7-fold), sulfoxaflor (7.6-fold) and isoprocarb (8.22-fold), while there was no cross-resistance to etofenprox, buprofezin and chlorpyrifos. Acetamiprid was synergized by the inhibitor piperonyl butoxide (2.2-fold) and the activity of cytochrome P450 monooxygenase was significantly higher in the AC-R strain compared with the AC-S strain, suggesting the critical role of P450. The gene expression results showed that the P450 gene CYP6ER1 was significantly overexpressed in AC-R compared with the AC-S and UNSEL strains. In addition, the RNA interference (RNAi) of CYP6ER1 significantly increased the susceptibility of AC-R to acetamiprid. Molecular docking predicted that acetamiprid and CYP6ER1 had close binding sites, and the nitrogen atoms had hydrogen bond interactions with CYP6ER1. These results demonstrated that the overexpression of CYP6ER1 contributed to acetamiprid resistance in N. lugens.

Naturally produced magnolol can significantly damage the plasma membrane of Rhizoctonia solani.

Rice sheath blight is a destructive fungal disease caused by Rhizoctonia solani. To find a safe and green measure, the biological activity of six plant extracts against R. solani was determined by mycelial growth rate method. The results showed that magnolol possessed better antifungal activities against R. solani, with an EC50 value of 7.47 mg/L. further action mechanism of magnolol against R. solani was carried out. Studies by scanning electron microscopy (SEM) showed that the morphology of R. solani mycelia was deformation and surface folds. Transmission electron microscope (TEM) observation on treated R. solani showed that magnolol could induce cytoplasmic membrane rupture and cytoplasmic membrane even disappeared completely accompanied with cellular debris was covered around this fungal, and the mycelia treated with magnolol showed fluorescence after PI staining. Further study showed that the content of malondialdehyde (MDA) and activity of chitinase, ß-1,3-glucanase and relative conductivity of mycelia were increased, while the content of soluble protein and activities of catalase (CAT), polyphenol oxidase (PPO), superoxide dismutase (SOD), succinate dehydrogenase (SDH) and NAD-malate dehydrogenase (NAD-MDH) were significantly decreased. These results indicated that magnolol could significantly damage the plasma membrane of R. solani, and interfere with cell respiratory metabolism, thus inhibiting the growth of mycelium.

Proteomic analysis reveals that naturally produced citral can significantly disturb physiological and metabolic processes in the rice blast fungus Magnaporthe oryzae.

Rice blast (Magnaporthe oryzae), a major fungal disease in rice producing areas all over the world as well as in China, seriously affects the safety of rice production. Citral, a mixture of Z/E and trans isomers, is a natural acycloid monoterpene compound with good bacteriostatic effect on rice blast. To further investigate the underlying molecular mechanism, a comparative proteomics analysis was conducted between citral-treated and non-treated M. oryzae spores through two-dimensional gel electrophoresis and MALDI-TOF mass spectrometry. Our analysis identified 1600-1800 proteins from M. oryzae ZB15, of which 147 were differentially expressed in 100 µg/mL citral-treated samples relative to the control group. Among these differentially expressed proteins (DEPs), 40 proteins showed significantly different expression. GO enrichment and NCBI conserved domains database analysis showed that the main groups of the cellular component were cytoplasm (23.33%), and the major molecular function categories were ion binding (31.37%), and the major categories of biological processes included small molecule metabolic process (22.22%) and transport (13.89%). Further analysis found that down-regulated proteins included the tubulin α chain, ATP synthase subunit ß and malate dehydrogenase, while the tubulin ß, enolase were upregulated. These DEPs could possibly limit the availability of energy required for many cellular processes and result in various physiological adaptions of M. oryzae. This study represents the first proteomic analysis of M. oryzae treated by citral and will help to uncover the mode-of-action of this biologically active compound against M. oryzae. These findings have practical implications with respect to the use of citral for fungal disease control.

Sulfur Induces Resistance against Canker Caused by Pseudomonas syringae pv. actinidae via Phenolic Components Increase and Morphological Structure Modification in the Kiwifruit Stems.

Bacterial canker caused by Pseudomonas syringae pv. actinidiae (Psa) has led to considerable losses in all major kiwifruit-growing areas. There are no commercial products in the market to effectively control this disease. Therefore, the defense resistance of host plants is a prospective option. In our previous study, sulfur could improve the resistance of kiwifruit to Psa infection. However, the mechanisms of inducing resistance remain largely unclear. In this study, disease severity and protection efficiency were tested after applying sulfur, with different concentrations in the field. The results indicated that sulfur could reduce the disease index by 30.26 and 31.6 and recorded high protection efficiency of 76.67% and 77.00% after one and two years, respectively, when the concentration of induction treatments was 2.0 kg/m3. Ultrastructural changes in kiwifruit stems after induction were demonstrated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and the activities of phenylalanine ammonia-lyase (PAL), peroxidase (POD) and polyphenol oxidase (PPO), and the accumulation of lignin were determined by biochemical analyses. Our results showed that the morphological characteristics of trichomes and lenticels of kiwifruit stem were in the best defensive state respectively when the sulfur concentration was 3.0 kg/m3 and 1.5 kg/m3. Meanwhile, in the range of 0.5 to 2.0 kg/m3, the sulfur could promote the chloroplast and mitochondria of kiwifruit stems infected with Psa to gradually return to health status, increasing the thickness of the cell wall. In addition, sulfur increased the activities of PAL, POD and PPO, and promoted the accumulation of lignin in kiwifruit stems. Moreover, the sulfur protection efficiency was positively correlated with PPO activity (p < 0.05) and lignin content (p < 0.01), which revealed that the synergistic effect of protective enzyme activity and the phenolic metabolism pathway was the physiological effect of sulfur-induced kiwifruit resistance to Psa. This evidence highlights the importance of lignin content in kiwifruit stems as a defense mechanism in sulfur-induced resistance. These results suggest that sulfur enhances kiwifruit canker resistance via an increase in phenolic components and morphology structure modification in the kiwifruit stems. Therefore, this study could provide insights into sulfur to control kiwifruit canker caused by Psa.

Growth Restriction of Rhizoctonia solani via Breakage of Intracellular Organelles Using Crude Extracts of Gallnut and Clove.

Plant diseases reduce crop yield and quality, hampering the development of agriculture. Fungicides, which restrict chemical synthesis in fungi, are the strongest controls for plant diseases. However, the harmful effects on the environment due to continued and uncontrolled utilization of fungicides have become a major challenge in recent years. Plant-sourced fungicides are a class of plant antibacterial substances or compounds that induce plant defenses. They can kill or inhibit the growth of target pathogens efficiently with no or low toxicity, they degrade readily, and do not prompt development of resistance, which has led to their widespread use. In this study, the growth inhibition effect of 24 plant-sourced ethanol extracts on rice sprigs was studied. Ethanol extract of gallnuts and cloves inhibited the growth of bacteria by up to 100%. Indoor toxicity measurement results showed that the gallnut and glove constituents inhibition reached 39.23 µg/mL and 18.82 µg/mL, respectively. Extract treated rice sprigs were dry and wrinkled. Gallnut caused intracellular swelling and breakage of mitochondria, disintegration of nuclei, aggregation of protoplasts, and complete degradation of organelles in hyphae and aggregation of cellular contents. Protection of Rhizoctonia solani viability reached 46.8% for gallnut and 37.88% for clove in water emulsions of 1000 µg/mL gallnut and clove in the presence of 0.1% Tween 80. The protection by gallnut was significantly stronger than that of clove. The data could inform the choice of plant-sourced fungicides for the comprehensive treatment of rice sprig disease. The studied extract effectively protected rice sprigs and could be a suitable alternative to commercially available chemical fungicides. Further optimized field trials are needed to effectively sterilize rice paddies.

Enhanced elimination of dimethachlon from soils using a novel strain Brevundimonas naejangsanensis J3.

Dimethachlon is a hazardous xenobiotic which poses a potential risk on the ecosystem and human health after foliar spray for mitigating fungal diseases of crops. A novel dimethachlon-degrading strain was isolated and identified as Brevundimonas naejangsanensis J3. Free cells and enzymes of this strain could rapidly eliminate 75 mg/L dimethachlon in liquid medium, especially the latter (>90% of degradation efficiency). Strain J3 completely metabolized dimethachlon by an ideally transformed pathway. Immobilization cells and enzymes exhibited better stability and adaptability for the repeated use, as compared with free cells and enzymes. In laboratory, 68.03 and 65.13%, or 82.67 and 95.41% of dimethachlon were eliminated from non-sterile soils by free or immobilized cells and enzymes within 7 d, respectively. Under the field condition, 95.78 and 98.01% of 20.250 kg a.i./ha dimethachlon wettable powder from soils were degraded by immobilized cells and enzymes in 9 d respectively, which were significant higher than the degradation efficiencies of free cells and enzymes (78.81 and 67.25%). This study highlights immobilized cells and enzymes from strain J3 can be applicable for bioremediating dimethachlon-contaminated soils.

Physicochemical Properties and Bioactivity of a New Guar Gum-Based Film Incorporated with Citral to Brown Planthopper, Nilaparvata lugens (Stål) (Hemiptera: Delphacidae).

The brown planthopper (BPH), Nilaparvata lugens (Stål), is the most notorious rice insect pest. In order to repel BPH effectively while being environmentally friendly, a new film based on guar gum incorporated with citral (GC film) was formulated. A toxicity bioassay of citral and guar gum at different proportions (ratios of 3:1, 2:1, 1:1, 1:2, and 1:3 in w/w) of GC film-forming emulsion to BPH was performed with the rice stem dipping method. Results showed that the most effective ratio of citral to guar gum was 1:1 with the median lethal concentration (LC50) of 4.30 mg/mL, far below the LC50 of guar gum (GG)/citral individual (141.51 and 44.38 mg/mL, respectively). The mortality of BPH adults and nymphs in the third instar treated with different dilution multiples of GC film-forming emulsion ranged from 46.67% to 82.22% and from 37.78% to 71.11%, respectively. These indicated that GC film-forming emulsion had a direct toxicity on BPH, and the mixture of citral and GG had synergistic interactions. Subsequently, Fourier-transform infrared spectroscopy showed that the incorporation of guar gum with citral was successful and did not result in the formation of new chemical bonds. The GC film exhibited a darker color and rougher surface topography with larger apertures and deeper gullies (Ra = 1.42 nm, Rq = 2.05 nm, and Rmax = 25.40 nm) compared to the guar gum film (GG film) (Ra = 1.00 nm, Rq = 1.33 nm, and Rmax = 16.40 nm), as determined by transmission electron microscopy and atomic force microscopy. The GC film exhibited a 50.4% lower solubility in water (30.30% vs. 15.00%) and 71.3% oxygen permeability (8.26 × 10-9 vs. 2.37 × 10-9 cm3/m2·d·Pa) (p < 0.05) but did not demonstrate any significant difference in mechanical properties, such as thickness (39.10 vs. 41.70 mm), tensile strength (41.89 vs. 38.30 N/mm2), and elongation at break (1.82% vs. 2.03%) (p < 0.05) compared to the GG film. Our findings established a link between physicochemical properties and bioactivity, which can provide useful information on developing and improving GC films and may offer an alternative approach for the control of BPH in the near future.

Effect of pre-discharge cardiopulmonary fitness on outcomes in patients with ST-elevation myocardial infarction after percutaneous coronary intervention.

BACKGROUND: The purpose of this study was to analyze cardiopulmonary fitness in Phase I cardiac rehabilitation on the prognosis of patients with ST-Elevation Myocardial Infarction (STEMI) after percutaneous coronary intervention (PCI). METHODS: The study enrolled a total of 499 STEMI patients treated with PCI between January 2015 and December 2015. Patients were assigned to individualized exercise prescriptions (IEP) group and non-individualized exercise prescriptions (NIEP) group according to whether they accept or refuse individualized exercise prescriptions. We compared the incidence of major cardiovascular events between the two groups. IEP group were further divided into two subgroups based on prognosis status, namely good prognosis (GP) group and poor prognosis (PP) group. Key cardio-pulmonary exercise testing (CPX) variables that may affect the prognosis of patients were identified through comparison of the cardio-respiratory fitness (CRF). RESULTS: There is no significant difference in the incidence of cardio-genetic death, re-hospitalization, heart failure, stroke, or atrial fibrillation between the IEP and the NIEP group. But the incidence of total major adverse cardiac events (MACE) was significantly lower in the IEP group than in the NIEP group (P = 0.039). The oxygen consumption (VO2) at ventilation threshold (VT), minute CO2 ventilation (E-VCO2), margin of minute ventilation carbon dioxide production (△CO2), rest partial pressure of end-tidal carbon dioxide(R-PETCO2), exercise partial pressure of end-tidal carbon dioxide(E-PETCO2) and margin of partial pressure of end-tidal carbon dioxide(△PETCO2) were significantly higher in the GP subgroup than in the PP subgroup; and the slope for minute ventilation/carbon dioxide production (VE/VCO2) was significantly lower in GP subgroup than in PP subgroup (P = 0.010). The VO2 at VT, VE/VCO2 slope, E-VCO2, △CO2, R-PETCO2, E-PETCO2 and margin of partial pressure of end-tidal carbon dioxide CO2 (△PETCO2) were predictive of adverse events. The VO2 at VT was an independent risk factor for cardiovascular disease prognosis. CONCLUSIONS: Individualized exercise prescription of Phase I cardiac rehabilitation reduced the incidence of cardiovascular events in patients with STEMI after PCI. VO2 at VT is an independent risk factor for cardiovascular disease prognosis, and could be used as an important evaluating indicator for Phase I cardiac rehabilitation.

Effects of conversion of mangroves into gei wai ponds on accumulation, speciation and risk of heavy metals in intertidal sediments.

Mangroves are often converted into gei wai ponds for aquaculture, but how such conversion affects the accumulation and behavior of heavy metals in sediments is not clear. The present study aims to quantify the concentration and speciation of heavy metals in sediments in different habitats, including gei wai pond, mangrove marsh dominated by Avicennia marina and bare mudflat, in a mangrove nature reserve in South China. The results showed that gei wai pond acidified the sediment and reduced its electronic conductivity and total organic carbon (TOC) when compared to A. marina marsh and mudflat. The concentrations of Cd, Cu, Zn and Pb at all sediment depths in gei wai pond were lower than the other habitats, indicating gei wai pond reduced the fertility and the ability to retain heavy metals in sediment. Gei wai pond sediment also had a lower heavy metal pollution problem according to multiple evaluation methods, including potential ecological risk coefficient, potential ecological risk index, geo-accumulation index, mean PEL quotients, pollution load index, mean ERM quotients and total toxic unit. Heavy metal speciation analysis showed that gei wai pond increased the transfer of the immobilized fraction of Cd and Cr to the mobilized one. According to the acid-volatile sulfide (AVS) and simultaneously extracted metals (SEM) analysis, the conversion of mangroves into gei wai pond reduced values of ([SEM] - [AVS])/foc, and the role of TOC in alleviating heavy metal toxicity in sediment. This study demonstrated the conversion of mangrove marsh into gei wai pond not only reduced the ecological purification capacity on heavy metal contamination, but also enhanced the transfer of heavy metals from gei wai pond sediment to nearby habitats.

Does ammonium nitrogen affect accumulation, subcellular distribution and chemical forms of cadmium in Kandelia obovata?

Heavy metals and nutrients are commonly found in mangrove sediments, but the effect of nutrients on heavy metals in mangrove plants is not clear. A study quantifying the effects of ammonium nitrogen (NH4+-N) on the accumulation, subcellular distribution and chemical forms of cadmium (Cd) in Kandelia obovata seedlings were conducted. The experiment consisted of four levels of NH4+-N (0, 10, 50 and 100 mg L-1) in each of which consisted of four Cd levels (0, 1, 5 and 10 mg L-1). The results showed that NH4+-N magnified the Cd toxicity due to reduced plant biomass, especially with 10 mg L-1 Cd and 100 mg L-1 NH4+-N supply. NH4+-N, especially at 100 mg L-1, enhanced the concentration and accumulation of Cd in root but its role on Cd translocation from root to stem and leaf was limited, probably due to low translocation factor. At subcellular level, Cd mainly accumulated in root cell wall but its fractionation depended on Cd levels. Under the stress of 1 and 5 mg L-1 Cd, 50 mg L-1 NH4+-N supply improved transfer of Cd from root cell wall into cell, and increased pectate and protein integrated forms of intracellular Cd to alleviate Cd toxicity. Under the stress of 10 mg L-1 Cd, NH4+-N supply promoted the deposition of Cd on root cell wall to restrain its transfer to root cell, which was verified by the reduced levels of pectate and protein integrated forms of Cd in root cell. Thus, NH4+-N supply improved immobilization of Cd in roots and alleviated Cd toxicity through integration with pectate and protein as well as cell wall combinations in root of K. obovata.