Serratia marcescens LYGN1 Reforms the Rhizosphere Microbial Community and Promotes Cucumber and Pepper Growth in Plug Seedling Cultivation.

The vegetable plug seedling plays an important role in improving vegetable production. The process of plug seedling contributes to high-quality vegetable seedlings. The substrate composition and chemical fertilizer are widely studied to promote seedling growth. However, little is known about the effect of beneficial bacteria in the rhizosphere microbial community and vegetables' growth during plug seedling. The use of beneficial microbes to promote vegetable seedling growth is of great potential. In this study, we showed that the Serratia marcescens strain LYGN1 enhanced the growth of cucumber and pepper seedlings in plug seedling cultivation. The treatment with LYGN1 significantly increased the biomass and the growth-related index of cucumber and pepper, improving the seedling quality index. Specifically, LYGN1 also improved the cucumber and pepper root system architecture and increased the root diameter. We applied high-throughput sequencing to analyze the microbial community of the seedlings' rhizosphere, which showed LYGN1 to significantly change the composition and structure of the cucumber and pepper rhizosphere microbial communities. The correlation analysis showed that the Abditibacteriota and Bdellovibrionota had positive effects on seedling growth. The findings of this study provide evidence for the effects of Serratia marcescens LYGN1 on the cucumber and pepper rhizosphere microbial communities, which also promoted seedling quality in plug seedling cultivation.

Thyroid dysfunction and risk of cutaneous malignant melanoma: a bidirectional two-sample Mendelian randomization study.

Background: Epidemiologic and observational data have found a risk association between thyroid dysfunction and cutaneous malignant melanoma (CMM), however, the cause and direction of these effects are yet unknown. By using a bidirectional two-sample Mendelian randomization (MR) methodology, we hoped to further investigate the causal link between thyroid dysfunction and CMM in this work. Methods: A genome-wide association study (GWAS) of 9,851,867 single nucleotide polymorphisms (SNPs) in a European population was used to develop genetic tools for thyroid dysfunction. Hypothyroidism was linked to 22,687 cases and 440,246 controls. For hyperthyroidism, there were 3545 cases and 459,388 controls. A total of 3751 cases and 372016 controls were included in the genetic data for CMM from UK Biobank (http://www.nealelab.is/uk-biobank) (the Dataset: ieu - b - 4969). Among them, inverse variance weighting (IVW) is the main MR Analysis method for causality assessment. MR-Egger method, MR Pleiotropic residual and outlier test (MR-PRESSO), and simple and weighted median (VM) were used to supplement the IVW method. Sensitivity analyses, mainly Cochran's Q test, leave-one-out analysis, and MR Egger intercept test were performed to assess the robustness of the outcomes. Results: The two-sample MR Analysis results revealed a negative correlation between genetically predicted hypothyroidism and the probability of CMM (OR=0.987, 95%CI =0.075-0.999, p=0.041). The supplemental MR Analysis did not reveal any statistically significant differences, although the direction of the effect sizes for the other approaches was consistent with the IVW effect sizes. The results of the causal analysis were relatively robust, according to a sensitivity analysis. The risk of CMM was unaffected by hyperthyroidism (p>0.05). No correlation between CMM and thyroid dysfunction was seen in the reverse MR analysis. Conclusion: Although the magnitude of the causal association is weak and further investigation of the mechanism of this putative causal relationship is required, our findings imply that hypothyroidism may be a protective factor for CMM.

Salt priming induces low-temperature tolerance in sugar beet via xanthine metabolism.

To understand the physiological mechanisms involved in xanthine metabolism during salt priming for improving low-temperature tolerance, salt priming (SP), xanthine dehydrogenase inhibitor (XOI), exogenous allantoin (EA), and back-supplemented EA (XOI + EA) treatments were given and the low-temperature tolerance of sugar beet was tested. Under low-temperature stress, salt priming promoted the growth of sugar beet leaves and increased the maximum quantum efficiency of PS II (Fv/Fm). However, during salt priming, either XOI or EA treatment alone increased the content of reactive oxygen species (ROS), such as superoxide anion and hydrogen peroxide, in the leaves under low-temperature stress. XOI treatment increased allantoinase activity with its gene (BvallB) expression under low-temperature stress. Compared to the XOI treatment, the EA treatment alone and the XOI + EA treatment increased the activities of antioxidant enzymes. At low temperatures, the sucrose content and the activity of key carbohydrate enzymes (AGPase, Cylnv, and FK) were significantly reduced by XOI compared to the changes under salt priming. XOI also stimulated the expression of protein phosphatase 2C and sucrose non-fermenting1-related protein kinase (BvSNRK2). The results of a correlation network analysis showed that BvallB was positively correlated with malondialdehyde, D-Fructose-6-phosphate, and D-Glucose-6-phosphate, and negatively correlated with BvPOX42, BvSNRK2, dehydroascorbate reductase, and catalase. These results suggested that salt-induced xanthine metabolism modulated ROS metabolism, photosynthetic carbon assimilation, and carbohydrate metabolism, thus enhancing low-temperature tolerance in sugar beet. Additionally, xanthine and allantoin were found to play key roles in plant stress resistance.

GhMYB102 promotes drought resistance by regulating drought-responsive genes and ABA biosynthesis in cotton (Gossypium hirsutum L.).

The MYB transcription factor (TF) family is among the largest TF families and plays an important role in plant growth and stress response. However, few studies have investigated the role of the MYB gene in drought resistance in cotton. In this study, we analysed the drought transcriptomic data of cotton and identified that the GhMYB102 gene was significantly upregulated in upland cotton during the early stages of drought stress. Bioinformatics analysis showed that the amino acid sequence encoded by GhMYB102 contained two highly conserved MYB binding domains belonging to R2R3-MYB TFs. GhMYB102 was most closely related to AtMYB102. GhMYB102 is mainly expressed in roots and is induced by abiotic stresses and abscisic acid (ABA); it is localised in the nucleus and has transcriptional activation activity. Silencing of GhMYB102 decreased plant drought resistance. In addition, dual-luciferase assays and yeast single hybridisation analysis showed that GhMYB102 could directly bind the MYB motif elements in the promoter regions of GhNCED1 and GhZAT10. These results indicate that GhMYB102 plays a positive role in drought tolerance by regulating the expression of GhNCED1 and GhZAT10. Thus, GhMYB102 enhances drought resistance by participating in ABA biosynthesis or regulating the expression of drought-responsive genes.

Scutellarin ameliorates hepatic lipid accumulation by enhancing autophagy and suppressing IRE1α/XBP1 pathway.

Nonalcoholic fatty liver disease is the most prevalent liver disease characterized by excessive lipid accumulation in hepatocytes. Endoplasmic reticulum (ER) stress and autophagy play an important role in lipid accumulation. In this study, scutellarin (Scu) was examined in palmitic acid-treated HepG2 cells and C57/BL6 mice fed a high-fat diet (HFD). Scu reduced intracellular lipid content and inhibited sterol regulatory element binding protein-1c (SREBP-1c)-mediated lipid synthesis and fatty acid translocase-mediated lipid uptake in HepG2 cells. Additionally, Scu restored impaired autophagy and inhibited excessive activation of ER stress in vivo and in vitro. Moreover, Scu upregulated forkhead box O transcription factor 1-mediated autophagy by inhibiting inositol-requiring enzyme 1α (IRE1α)/X-box-binding protein 1 (XBP1) branch activation, while XBP1s overexpression exacerbated the lipid accumulation and impaired autophagy in HepG2 cells and also weakened the positive effects of Scu. Furthermore, Scu attenuated ER stress by activating autophagy, ultimately downregulating SREBP-1c-mediated lipid synthesis, and autophagy inhibitors offset these beneficial effects. Scu inhibited the crosstalk between autophagy and ER stress and downregulated saturated fatty acid-induced lipid accumulation in hepatocytes. These findings demonstrate that Scu ameliorates hepatic lipid accumulation by enhancing autophagy and suppressing ER stress via the IRE1α/XBP1 pathway.

The Smartphone-Assisted Intervention Improved Perception of Nutritional Status among Middle School Students.

Misperception of nutritional status is common and hinders the progress of childhood obesity prevention. This study aimed to examine the effectiveness of a smartphone-assisted intervention to improve student and parental perception of students' nutritional status (underweight, normal weight, overweight, obese). We conducted a parallel-group controlled trial with a non-randomized design in three junior middle schools of Beijing, China in 2019. One school was allocated to the intervention group and two schools to the control group. A total of 573 students (aged 13.1 ± 0.4 years) participated in the trial. The 3-month intervention included three components: health education sessions for students and parents, regular monitoring of students' weight, and the provision of feedback via a smartphone application. Schools in the control group continued their usual practice. Primary outcomes included the student and parental accurate perception of students' nutritional status. The percentage of students' accurate perception of their own nutritional status in the intervention group increased from 49.0% to 59.2% from baseline to three months, whereas it decreased from 64.1% to 58.1% in the control group; the adjusted odds ratio (OR) between the two groups was 1.71 (95% confidence interval (CI): 1.13, 2.59). The intervention did not significantly improve parental perception of students' nutritional status (p > 0.05). The study findings provided a brief approach for improving perception of nutritional status among middle school students.

Scutellarin, a modulator of mTOR, attenuates hepatic insulin resistance by regulating hepatocyte lipid metabolism via SREBP-1c suppression.

High levels of consumption of saturated lipids have been largely associated with the increasing prevalence of metabolic diseases. In particular, saturated fatty acids such as palmitic acid (PA) have been implicated in the development of insulin resistance (IR). Scutellarin (Scu) is one of the effective traditional Chinese medicines considered beneficial for liver diseases and diabetes. In this study, we investigated the effect of Scu on IR and lipid metabolism disorders in vitro and in high fat diet (HFD)-fed mice. In vitro, we found that Scu decreased insulin-dependent lipid accumulation and the mRNA expression of CD36, Fasn, and ACC in PA-treated HepG2 cells. Additionally, Scu upregulated Akt phosphorylation and improved the insulin signalling pathway. Moreover, Scu downregulated mammalian target of rapamycin (mTOR) phosphorylation and the n-SREBP-1c protein level and also reduced lipid accumulation via the mTOR-dependent pathway, as confirmed by the molecular docking of Scu to mTOR. In HFD-fed C57BL/6 mice, Scu improved oral glucose tolerance, pyruvate tolerance and the IR index and also increased the Akt phosphorylation level. Moreover, Scu reduced hepatocyte steatosis, decreased lipid accumulation and triglyceride levels, inhibited mTOR phosphorylation, and decreased the SREBP-1c level in the liver. Taken together, these findings suggest that Scu ameliorates hepatic IR by regulating hepatocyte lipid metabolism via the mTOR-dependent pathway through SREBP-1c suppression.

Ethyl Rosmarinate Protects High Glucose-Induced Injury in Human Endothelial Cells.

Ethyl rosmarinate (RAE) is one of the active constituents from Clinopodium chinense (Benth.) O. Kuntze, which is used for diabetic treatment in Chinese folk medicine. In this study, we investigated the protective effect of RAE on high glucose-induced injury in endothelial cells and explored its underlying mechanisms. Our results showed that both RAE and rosmarinic acid (RA) increased cell viability, decreased the production of reactive oxygen species (ROS), and attenuated high glucose-induced endothelial cells apoptosis in a dose-dependent manner, as evidenced by Hochest staining, Annexin V⁻FITC/PI double staining, and caspase-3 activity. RAE and RA both elevated Bcl-2 expression and reduced Bax expression, according to Western blot. We also found that LY294002 (phosphatidylinositol 3-kinase, or PI3K inhibitor) weakened the protective effect of RAE. In addition, PDTC (nuclear factor-κB, or NF-κB inhibitor) and SP600125 (c-Jun N-terminal kinase, or JNK inhibitor) could inhibit the apoptosis in endothelial cells caused by high glucose. Further, we demonstrated that RAE activated Akt, and the molecular docking analysis predicted that RAE showed more affinity with Akt than RA. Moreover, we found that RAE inhibited the activation of NF-κB and JNK. These results suggested that RAE protected endothelial cells from high glucose-induced apoptosis by alleviating reactive oxygen species (ROS) generation, and regulating the PI3K/Akt/Bcl-2 pathway, the NF-κB pathway, and the JNK pathway. In general, RAE showed greater potency than RA equivalent.

Application of Sodium Silicate Enhances Cucumber Resistance to Fusarium Wilt and Alters Soil Microbial Communities.

Exogenous silicates can enhance plant resistance to pathogens and change soil microbial communities. However, the relationship between changes in soil microbial communities and enhanced plant resistance remains unclear. Here, effects of exogenous sodium silicate on cucumber (Cucumis sativus L.) seedling resistance to Fusarium wilt caused by the soil-borne pathogen Fusarium oxysporum f.sp. cucumerinum Owen (FOC) were investigated by drenching soil with 2 mM sodium silicate. Soil bacterial and fungal community abundances and compositions were estimated by real-time PCR and high-throughput amplicon sequencing; then, feedback effects of changes in soil biota on cucumber seedling resistance to FOC were assessed. Moreover, effects of sodium silicate on the growth of FOC and Streptomyces DHV3-2, an antagonistic bacterium to FOC, were investigated both in vitro and in the soil environment. Results showed that exogenous sodium silicate enhanced cucumber seedling growth and resistance to FOC. In bare soil, sodium silicate increased bacterial and fungal community abundances and diversities. In cucumber-cultivated soil, sodium silicate increased bacterial community abundances, but decreased fungal community abundances and diversities. Sodium silicate also changed soil bacterial and fungal communality compositions, and especially, decreased the relative abundances of microbial taxa containing plant pathogens but increased these with plant-beneficial potentials. Moreover, sodium silicate increased the abundance of Streptomyces DHV3-2 in soil. Soil biota from cucumber-cultivated soil treated with sodium silicate decreased cucumber seedling Fusarium wilt disease index, and enhanced cucumber seedling growth and defense-related enzyme activities in roots. Sodium silicate at pH 9.85 inhibited FOC abundance in vitro, but did not affect FOC abundance in soil. Overall, our results suggested that, in cucumber-cultivated soil, sodium silicate increased cucumber seedling resistance to Fusarium wilt by changing soil microbial communities rather than by directly inhibiting the growth of FOC.

Increased Expression of P-Glycoprotein Is Associated With Chlorpyrifos Resistance in the German Cockroach (Blattodea: Blattellidae).

A principal method for control of the German cockroach, Blattella germanica (L.), is the broad-spectrum organophosphorus insecticide, chlorpyrifos (O,O-diethyl O-3,5,6-trichloro-2-pyridyl phosphorothioate); however, extensive and repeated application has resulted in the development of resistance to chlorpyrifos in this insect. Evidence suggests that ATP-binding cassette protein transporters, including P-glycoprotein, are involved in insecticide resistance. However, little is known of the role of P-glycoprotein in insecticide resistance in the German cockroach. Here, we developed a chlorpyrifos-resistant strain of German cockroach and investigated the relationship between P-glycoprotein and chlorpyrifos resistance using toxicity assays; inhibition studies with two P-glycoprotein inhibitors, verapamil and quinine; P-glycoprotein-ATPase activity assays; and western blotting analysis. After 23 generations of selection from susceptible strain cockroaches, we obtained animals with high resistance to chlorpyrifos. When P-glycoprotein-ATPase activity was inhibited by verapamil and quinine, we observed enhanced susceptibility to chlorpyrifos in both control and chlorpyrifos-resistant cockroaches. No significant alterations of P-glycoprotein expression or ATPase activity were observed in cockroaches acutely exposed to LD50 doses of chlorpyrifos for 24 h, while P-glycoprotein expression and ATPase activity were clearly elevated in the chlorpyrifos-resistant cockroach strain. Thus, we conclude that P-glycoprotein is associated with chlorpyrifos resistance in the German cockroach and that elevated levels of P-glycoprotein expression and ATPase activity may be an important mechanism of chlorpyrifos resistance in the German cockroach.

Companion cropping with potato onion enhances the disease resistance of tomato against Verticillium dahliae.

Intercropping could alleviate soil-borne diseases, however, few studies focused on the immunity of the host plant induced by the interspecific interactions. To test whether or not intercropping could enhance the disease resistance of host plant, we investigated the effect of companion cropping with potato onion on tomato Verticillium wilt caused by Verticillium dahliae (V. dahliae). To investigate the mechanisms, the root exudates were collected from tomato and potato onion which were grown together or separately, and were used to examine the antifungal activities against V. dahliae in vitro, respectively. Furthermore, RNA-seq was used to examine the expression pattern of genes related to disease resistance in tomato companied with potato onion compared to that in tomato grown alone, under the condition of infection with V. dahliae. The results showed that companion cropping with potato onion could alleviate the incidence and severity of tomato Verticillium wilt. The further studies revealed that the root exudates from tomato companied with potato onion significantly inhibited the mycelia growth and spore germination of V. dahliae. However, there were no significant effects on these two measurements for the root exudates from potato onion grown alone or from potato onion grown with tomato. RNA-seq data analysis showed the disease defense genes associated with pathogenesis-related proteins, biosynthesis of lignin, hormone metabolism and signal transduction were expressed much higher in the tomato companied with potato onion than those in the tomato grown alone, which indicated that these defense genes play important roles in tomato against V. dahliae infection, and meant that the disease resistance of tomato against V. dahliae was enhanced in the companion copping with potato onion. We proposed that companion cropping with potato onion could enhance the disease resistance of tomato against V. dahliae by regulating the expression of genes related to disease resistance response. This may be a potential mechanism for the management of soil-borne plant diseases in the intercropping system.

[The hypolipidemic and liver protective effect of (Z)-N-(2-hydroxyethyl) docos-13-enamide on hyperlipidemic golden hamsters].

This study is to observe preventive effect of (Z)-N-(2-hydroxyethyl) docos-13-enamide on hyperlipidemia and fatty liver of golden hamsters. Hyperlipidemic golden hamsters fed with high-fat diet was administered orally with (Z)-N-(2-hydroxyethyl) docos-13-enamide (10, 20 and 40 mg x kg(-1)) for 5 weeks. Levels of serum and hepatic lipid content, liver histology, hepatic MDA and SOD levels, serum ALT and AST levels were evaluated in golden hamsters. (Z)-N-(2-Hydroxyethyl) docos-13-enamide has a hypolipidemic effect, and could reduce hepatic lipid content, serum ALT and AST levels, hepatic MDA level, increase hepatic SOD activity. (Z)-N-(2-Hydroxyethyl) docos-13-enamide plays an important role in reducing serum lipid, restraining hepatic fatty deposition and protecting liver to get rid of peroxidation injury of hyperlipidemic golden hamsters. The exact lipid-lowering mechanism of (Z)-N-(2-hydroxyethyl) docos-13-enamide needs further investigation.

Tissue distribution of s-oleylpropanolamide in rats detected by liquid chromatography with tandem mass spectrometry.

This paper is to report the development of a rapid and sensitive method for the determination of s-oleylpropanolamide (OPA) in various tissues of rat (brain, heart, lung, liver, spleen, small intestine, kidney, adipose tissue and muscle), and to assess the applicability of the assay to tissue distribution. OPA was extracted by liquid-liquid extraction method with undecylenoylethanolamide as an internal standard. The concentrations of OPA were determined by LC-MS/MS after a single intragastric dose of 50 mg x kg(-1) at 4 time points (5 rats per group). With multiple reactions monitoring mode (MRM) the limit of quantification (LLOQ) was determined at 1 microg x L(-1). The calibration curve was linear from 1 to 2 x 104 microg x L(-1) (r > or = 0.999 0) for tissue homogenates. Validation parameters such as accuracy, precision and recovery were found to be within the acceptance criteria of the assay validation guidelines. The highest concentration was found in small intestine (the highest time point is 15 min) and heart (the highest time point is 90 min). The assay is rapid, sensitive and applicable to studying tissue distribution of OPA in rats.

Inhibition of TNFα-induced adhesion molecule expression by (Z)-(S)-9-octadecenamide, N-(2-hydroxyethyl,1-methyl).

Inflammation is a primary event in atherogenesis. Oleoylethanolamide (OEA), a naturally occurring fatty-acid ethanolamide, lowers lipid levels in liver and blood through activation of the nuclear receptor, peroxisome proliferator-activated receptor-alpha (PPARα). We designed and synthesized (Z)-(S)-9-octadecenamide, N-(2-hydroxyethyl, 1-methyl) (OPA), an OEA analog. The present study investigated the effect of OPA on the expression of adhesion molecules in human umbilical vein endothelial cells (HUVEC). OPA inhibited expression of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) stimulated by Tumor Necrosis Factor-α (TNF-α) via activation of PPARα. This inhibition of VCAM-1 and ICAM-1 expression decreased adhesion of monocyte-like cells to stimulated endothelial cells. These results demonstrate that OPA may have anti-inflammatory properties. Our results thus provide new insights into possible future therapeutic approaches to the treatment of atherosclerosis.

[A community-based epidemiologic study on gastroesophageal reflux disease in Haidian district of Beijing].

OBJECTIVE: To explore the prevalence of gastroesophageal reflux disease (GERD) and its symptoms in Haidian district of Beijing, identify its associated risk factors and analyze the relations between GERD and history of other diseases. METHODS: 2615 residents of 18-80 years old were selected to participate in the study by multi-stage sampling from Haidian district from June and September in 2008. Questionnaires were distributed to obtain the information on demographic characteristics, diseases history and the reflux disease questionnaire (RDQ). RESULTS: The prevalence of GERD in the population was 8.4% (220/2615), and the prevalence of heartburn, reflux, both heartburn and reflux were 1.0% (25/2615), 6.2% (163/2615) and 1.2% (32/2615), respectively. Multi-factor analysis showed rural area (OR = 2.237, 95%CI: 1.422 - 3.517), female (OR = 1.456, 95%CI: 1.085 - 1.955), high education (OR = 1.242, 95%CI: 1.001 - 1.542), pressure (OR = 1.277, 95%CI: 1.089 - 1.497), bad emotional status (OR = 1.320, 95%CI: 1.046 - 1.665), and family history of gastrointestinal disorders (OR = 1.594, 95%CI: 1.075 - 2.365) were significantly associated with GERD. Rural area (OR = 2.481, 95%CI: 1.278 - 4.818), female (OR = 1.747, 95%CI: 0.902 - 3.386), drinking (OR = 1.838, 95%CI: 0.916 - 3.690), no exercise (OR = 2.091; 95%CI: 1.131 - 3.867) and bad emotional status (OR = 1.657, 95%CI: 1.123 - 2.446) were significant risk factors for heartburn. Rural area (OR = 2.171, 95%CI: 1.326 - 3.556), female (OR = 1.505, 95%CI: 1.102 - 2.056), high education (OR = 1.347, 95%CI: 1.063 - 1.706), pressure (OR = 1.317, 95%CI: 1.113 - 1.558), bad emotional status (OR = 1.266, 95%CI: 0.992 - 1.616), and family history of gastrointestinal disorders (OR = 1.739, 95%CI: 1.163 - 2.600) were significantly associated with reflux symptom. History of diseases such as inflammatory bowel disease, anxiety, depression, peptic ulcer, gastritis, and renal diseases were found to be significantly related to GERD and its symptoms. CONCLUSION: This area has epidemic of GERD, which was related to mental problems and unhealthy life style, and should be paid more attention by conducting effective community-based interventions.