A biological product of Bacillus amyloliquefaciens QST713 strain for promoting banana plant growth and modifying rhizosphere soil microbial diversity and community composition.

Introduction: Bananas are not only an important food crop for developing countries but also a major trading fruit for tropical and semitropical regions, maintaining a huge trade volume. Fusarium wilt of banana (FWB) caused by Fusarium oxysporum f. sp. cubense is becoming a serious challenge to the banana industry globally. Biological control has the potential to offer both effective and sustainable measures for this soil-borne disease. Methods: In order to explore the biocontrol effects of the biological agent Bacillus amyloliquefaciens QST713 strain on banana plants, two cultivars, Brazilian and Yunjiao No. 1, with varied resistance to FWB, were used in greenhouse pot experiments. Results: Results showed that the plant height and pseudostem diameter of banana-susceptible cultivar Brazilian increased by 11.68% and 11.94%, respectively, after QST713 application, while the plant height and pseudostem diameter of resistant cultivar Yunjiao No. 1 increased by 14.87% and 12.51%, respectively. The fresh weight of the two cultivars increased by 20.66% and 36.68%, respectively, indicating that this biological agent has potential effects on plant growth. Analysis of the rhizosphere soil microbial communities of two different cultivars of banana plants showed that TR4 infection and B. amyloliquefaciens QST713 strain application significantly affected the bacterial and fungal diversity of Yunjiao No. 1, but not in the cultivar Brazilian. In addition, TR4 infection and QST713 application changed the bacterial community composition of both banana cultivars, and the fungal community composition of Yunjiao No. 1 also changed significantly. Relevance analysis indicated that the relative richness of Bacillus and Pseudomonas in the rhizosphere of both cultivars increased significantly after QST713 application, which had a good positive correlation with plant height, pseudostem girth, aboveground fresh weight, leaf length, and leaf width. Discussion: Therefore, the outcome of this study suggests that the biological agent QST713 strain has potential application in banana production for promoting plant growth and modification of soil microbial communities, particularly in the TR4-infected field.

Banana disease-suppressive soil drives Bacillus assembled to defense Fusarium wilt of banana.

Fusarium wilt of banana (FWB) caused by Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4), poses a serious problem for sustainable banana production. Biological control is one of the effective measures to control this destructive disease. High-throughput sequencing of soil microorganisms could significantly improve the efficiency and accuracy of biocontrol strain screening. In this study, the soil microbial diversity of six main banana-producing areas in Yunnan was sequenced by Illumina Miseq platform. The outcome of this study showed the genus of Chujaibacter, Bacillus, and Sphingomonas were significantly enriched in microorganism community composition. Further correlation analysis with soil pathogen (Foc TR4) content showed that Bacillus was significantly negatively correlated with pathogen content. Therefore, we isolated and identified Bacillus from the disease-suppressive soils, and obtained a B. velezensis strain YN1910. In vitro and pot experiments showed that YN1910 had a significant control effect (78.43-81.76%) on banana Fusarium wilt and had a significant growth promotion effect on banana plants.

Effect of natural weed and Siratro cover crop on soil fungal diversity in a banana cropping system in southwestern China.

Introduction: Natural weed cover and a legume cover crop were examined to determine if they could impact soil fungal diversity as an indicator of soil quality in banana production. Methods: Banana in Yunnan Province, China, was grown under three treatments: conventional tillage (bare soil), natural weed cover (primarily goosegrass (Eleusine indica (L.) Gaerth)), or a cover crop (Siratro (Macroptilium atropurpureum (DC.) Urb.)). Analysis of the soil fungal communities between 2017 and 2020 was done by Illumina Miseq high-throughput sequencing. Results: Most significant effects were in the intercropping area for the treatments, whereas it was rarely observed in the furrow planted with banana. Based on the Shannon and Simpson diversity indices, soil fungal diversity in the intercropping area significantly decreased following planting banana in 2017 with all three treatments. However, both the Shannon and Simpson diversity indices showed that there were significant increases in fungal soil diversity in 2019 and 2020 with natural weed cover or Siratro compared to bare soil. At the end of the experiment, significant increases in fungal genera with Siratro compared to bare soil were observed with Mortierella, Acremonium, Plectophaerella, Metarhizium and Acrocalymma, and significant decreases were observed with Fusicolla, Myrothecium, Exserohilum, Micropsalliota and Nigrospora. Siratro resulted in higher stability of the soil fungal microbiome by increasing the modularity and the proportion of negative co-occurrences compared to bare soil. For fungal guilds, Siratro significantly increased saprotrophs_symbiotrophs in 2019 and 2020 and significantly decreased pathogens_saprotrophs in 2020 compared to bare soil. Discussion: Using Siratro as a cover crop in the intercropping area of banana helped maintain soil fungal diversity, which would be beneficial for soil health with more symbiotrophs and less pathogens in the soil. However, further research is needed to determine the long-term impact of weed or Siratro cover crop on the fungal soil ecosystem and growth of banana.

Disentangling the resistant mechanism of Fusarium wilt TR4 interactions with different cultivars and its elicitor application.

Fusarium wilt of banana, especially Tropical Race 4 (TR4) is a major factor restricting banana production. Developing a resistant cultivar and inducing plant defenses by elicitor application are currently two of the best options to control this disease. Isotianil is a monocarboxylic acid amide that has been used as a fungicide to control rice blast and could potentially induce systemic acquired resistance in plants. To determine the control effect of elicitor isotianil on TR4 in different resistant cultivars, a greenhouse pot experiment was conducted and its results showed that isotianil could significantly alleviate the symptoms of TR4, provide enhanced disease control on the cultivars 'Baxi' and 'Yunjiao No.1' with control effect 50.14% and 56.14%, respectively. We compared the infection processes in 'Baxi' (susceptible cultivars) and 'Yunjiao No.1' (resistant cultivars) two cultivars inoculated with pathogen TR4. The results showed that TR4 hyphae could rapidly penetrate the cortex into the root vascular bundle for colonization, and the colonization capacity in 'Baxi' was significantly higher than that in 'Yunjiao No.1'. The accumulation of a large number of starch grains was observed in corms cells, and further analysis showed that the starch content in 'Yunjiao No. 1' as resistant cultivar was significantly higher than that in 'Baxi' as susceptible cultivar, and isotianil application could significantly increase the starch content in 'Baxi'. Besides, a mass of tyloses were observed in the roots and corms and these tyloses increased after application with isotianil. Furthermore, the total starch and tyloses contents and the control effect in the corms of 'Yunjiao No.1' was higher than that in the 'Baxi'. Moreover, the expression levels of key genes for plant resistance induction and starch synthesis were analyzed, and the results suggested that these genes were significantly upregulated at different time points after the application of isotianil. These results suggest that there are significant differences between cultivars in response to TR4 invasion and plant reactions with respect to starch accumulation, tyloses formation and the expression of plant resistance induction and starch synthesis related genes. Results also indicate that isotianil application may contribute to disease control by inducing host plant defense against TR4 infection and could be potentially used together with resistant cultivar as integrated approach to manage this destructive disease. Further research under field conditions should be included in the next phases of study.

Monitoring Tritrophic Biocontrol Interactions Between Bacillus spp., Fusarium oxysporum f. sp. cubense, Tropical Race 4, and Banana Plants in vivo Based on Fluorescent Transformation System.

Bacillus spp. is effective biocontrol agents for Fusarium wilt of banana (FWB), tropical race 4 (TR4). This study explores the colonization by Bacillus subtilis, Bacillus velezensis, and Bacillus amyloliquefaciens of host banana plants and elucidates the mechanism of antagonistic TR4 biocontrol. The authors selected one B. subtilis strain, three B. velezensis strains, and three B. amyloliquefaciens strains that are proven to significantly inhibit TR4 in vitro, optimized the genetic transformation conditions and explored their colonization process in banana plants. The results showed that we successfully constructed an optimized fluorescent electro-transformation system (OD600 of bacteria concentration=0.7, plasmid concentration=50ng/µl, plasmid volume=2µl, transformation voltage=1.8kV, and transformation capacitance=400Ω) of TR4-inhibitory Bacillus spp. strains. The red fluorescent protein (RFP)-labeled strains were shown to have high stability with a plasmid-retention frequency above 98%, where bacterial growth rates and TR4 inhibition are unaffected by fluorescent plasmid insertion. In vivo colonizing observation by Laser Scanning Confocal Microscopy (LSCM) and Scanning Electron Microscopy (SEM) showed that Bacillus spp. can colonize the internal cells of banana plantlets roots. Further, fluorescent observation by LSCM showed these RFP-labeled bacteria exhibit chemotaxis (chemotaxis ratio was 1.85±0.04) toward green fluorescent protein (GFP)-labeled TR4 hyphae in banana plants. We conclude that B. subtilis, B. velezensis, and B. amyloliquefaciens can successfully colonize banana plants and interact with TR4. Monitoring its dynamic interaction with TR4 and its biocontrol mechanism is under further study.

Changes of cardiolipin involve in the occurrence and development of mitochondrial dysfunction associated with non-alcoholic fatty liver disease. / å¿ƒç£·è„‚å˜åŒ–å‚ä¸Žéžé ’ç²¾æ€§è„‚è‚ªæ€§è‚ç— ç›¸å ³çº¿ç²’ä½“åŠŸèƒ½éšœç¢çš„å‘ç”Ÿå’Œå‘å±•.

Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases, which is often accompanied by mitochondrial dysfunction. Cardiolipin is a special lipid of mitochondrial inner membrane and any change of cardiolipin may cause series of mitochondria-relevant diseases. Changes in cardiolipin content, fatty acid side chain composition after cardiolipin remodeling, and the content of cardiolipin remodeling enzymes play an important role in the occurrence and development of NAFLD-related mitochondrial dysfunction.

Molecular mechanism underlying the effect of illumination time on the growth performance of broilers via changes in the intestinal bacterial community.

The circadian rhythms associated with light have important effects on the growth, metabolism, immunity and reproduction of broilers. However, there is a lack of systematic evaluations of the effect of the light cycle on intestinal microbes and the nutritional metabolism of these microbes in broilers. This study was designed to study the effects of the light cycle on the intestinal bacterial community structure and growth of broilers. In this study, Arbor Acre (AA) broilers were fed under a short photoperiod (1L:23D), a long photoperiod (23L:1D), and a normal photoperiod (16L:8D), respectively. The feed conversion ratio of the broilers was calculated, and the levels of endocrine hormones, such as melatonin, insulin and glucagon, were determined. Intestinal contents were collected from the small intestines of the broilers after slaughtering, and the V3+V4 region of the 16s rDNA gene was sequenced. The results demonstrated that changes in the light cycle could affect the synthetic rhythms of melatonin, insulin and glucagon. Compared to short and normal photoperiod, long photoperiod significantly increased the abundances of Barnesiella species in intestinal microbes and decreased the abundances of Bacteroides and Alistipes species. Cluster of Orthologous Groups of proteins analysis indicated that prolongation of the illumination increased the abundances of bacterial genes with glycometabolic and membrane transport functions in intestinal microorganisms. A model was established in this study, and our results showed that prolonged illumination altered the intestinal microbial community structures of broilers, increased the absorption and utilization of polysaccharides in broilers, and reduced the feed-to-meat ratios. To the best of our knowledge, this is also the first study to describe the molecular mechanism underlying the effects of the light cycle on the uptake and utilization of nutrients that occur via modification of the intestinal microbial community structure in broilers.

[Effect of epigallocatechin-3-gallate on liver lipid metabolism in rats with intrauterine growth restriction and related mechanism].

OBJECTIVE: To study the effect of epigallocatechin-3-gallate (EGCG) on liver lipid metabolism in rats with intrauterine growth restriction (IUGR) and related mechanism. METHODS: A rat model of IUGR was established by food restriction during entire pregnancy, and then the rats were randomly divided into an IUGR group and an EGCG group (n=8 each). The rats in the EGCG group were fed with water containing EGCG from after weaning to 10 weeks. Eight pup rats born from the pregnant maternal rats without food restriction were used as the control group. At the age of 13 weeks, body weight was measured. Blood and liver tissue samples were collected to measure fasting total cholesterol (TC), triglyceride (TG), free fatty acid (FFA), fasting plasma glucose (FPG), fasting insulin (FINS), and liver lipids. Homeostasis model assessment of insulin resistance (HOMA-IR) and adipose insulin resistance (adipo-IR) were calculated. Pathological sections of the liver were observed and quantitative real-time PCR was used to measure the mRNA expression of related genes in the liver. RESULTS: At the age of 13 weeks, there was no significant difference in body weight between groups (P=0.067). There were significant differences between groups in FPG, FFA, FINS, HOMA-IR, and adipo-IR (P<0.05). There were no significant differences in the serum levels of TC and TG between groups (P>0.05), while the IUGR group had significantly higher levels of TC and TG in the liver than the EGCG group (P<0.05). Oil red staining showed that the IUGR group had a significant increase in hepatic lipid accumulation, while the EGCG group had certain improvement after EGCG treatment. PCR results suggested that compared with the control group, the IUGR group had significant reductions in the mRNA expression of Ampk and Adipor1 and a significant increase in the mRNA expression of Srebf1 (P<0.05), while EGCG increased the mRNA expression of Ampk and reduced the mRNA expression of Srebf1, with no significant differences in the two indices between the EGCG and control groups (P>0.05). CONCLUSIONS: Early EGCG intervention can down-regulate the de novo synthesis of fatty acids through the Ampk/Srebf1 signaling pathway and reduce hepatic lipid accumulation in IUGR rats by improving insulin resistance of hepatocytes.

Stimulation role of epinephrine in transcription of the melatonin synthesis key enzyme AANAT in the pineal gland of broilers.

Melatonin is a crucial neurohormone synthesized in the pineal gland that influences the physiology of animals. The molecular mechanism of norepinephrine control of the synthesis of melatonin is well documented; however, few reports have described the effects of epinephrine on the synthesis of melatonin. In this study, the effect of epinephrine on melatonin synthesis was investigated by adding different concentrations of epinephrine or norepinephrine to broiler pineal glands cultured in vitro. In addition, we investigated how epinephrine regulates the synthesis of melatonin and the transcription of the key melatonin synthesis enzyme AANAT. We determined the abundance of melatonin, norepinephrine, and epinephrine in broiler serum and the mRNA expression levels of key enzymes under different light conditions. The minimum concentrations of epinephrine and norepinephrine required to recover the melatonin synthesis rhythm in pineal cells were 10-13 and 10-11 mol/L, respectively. Under various light durations, epinephrine reached maximum levels two hours earlier than melatonin. These results demonstrate for the first time that epinephrine can increase the synthesis of melatonin by increasing the transcription of AANAT.

Omega-3 fatty acids as a treatment for non-alcoholic fatty liver disease in children: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: The most typical chronic liver disease in children and adolescents is non-alcoholic fatty liver disease (NAFLD). The dietary addition of ω-3 polyunsaturated fatty acids (PUFAs) provides a promising therapy for children with NAFLD due to its convenience and safety; however, several studies suggested contradictory results for PUFA supplementation in children. Hence, we performed a systematic review and meta-analysis to evaluate the effectiveness of PUFA supplementation in children with NAFLD. METHODS: Published randomized controlled trials (RCTs) that evaluated the effectiveness of the dietary addition of PUFA in children with NAFLD were considered. The primary result was the alteration in hepatic steatosis grade on ultrasound after treatment. The secondary outcomes included alanine aminotransferase (ALT), aspartate aminotransferase (AST), C-reactive protein (CRP) and components of metabolic syndrome. Predefined sensitivity analysis was also performed to explore possible explanations for heterogeneity in the evaluations. RESULTS: In total, 4 studies with 263 subjects were identified. PUFA supplementation was associated with significantly improved hepatic steatosis grade on ultrasound (risk difference: 25%, 95% CI: 12-38%), without heterogeneity (P = 0.27, I2 = 24%). Sensitivity analysis confirmed the robustness of our findings. PUFA supplementation could decrease AST levels after 6 months, but could only reduce ALT levels after 12 months. PUFA did not have a significant effect on most components of metabolic syndrome and the CRP level. CONCLUSION: ω-3 PUFA supplementation can improve liver steatosis and liver functions, and it is a potential food supplementation to treat NAFLD in children.

Appraising the quality of clinical practice guidelines in traditional Chinese medicine using AGREE II instrument: A systematic review.

OBJECTIVES: The aim of this study was to investigate the quality of clinical practice guidelines (CPGs) of traditional Chinese medicine (TCM) published in journals and books using AGREE II instrument for further enhancing TCM CPG development. METHODS: A systematic search of relevant guideline websites and literature databases (including Chinese Guideline Clearinghouse, PubMed Wanfang Data Knowledge Service Platform, VIP Online Publishing Platform, China National Knowledge Infrastructure and SinoMed) was undertaken from inception to December, 2015 to identify and select CPGs related to TCM. Four independent reviewers assessed the eligible TCM CPGs using the Appraisal of Guidelines for Research and Evaluation (AGREE II) instrument. Their degree of agreement was evaluated by intra-class correlation coefficient (ICC). RESULTS: From 2380 citations, 115 TCM CPGs were included. The mean scores for each AGREE II domain were as follows: (i) scope and purpose (mean±SD=41.1±19.6); (ii) stakeholder involvement (mean±SD=37.6±15.1); (iii) rigour of development (mean±SD=20.1±10.9); (iv) clarity and presentation (mean±SD=33.3±15.4); (v) applicability (mean±SD=10.5±4.5) and (vi) editorial independence (mean±SD=11.4±7.6). Only 10% (n=12) TCM CPGs were rated as "recommended". The ICC values for TCM CPGs appraisal using the AGREE II ranged from 0.76 to 0.93. CONCLUSIONS: The quality of TCM CPGs has remained suboptimal according to AGREE II instrument evaluation. The use of AGREE II in the development process ensures that these considerations are incorporated, and more efforts must be made to improve the quality of TCM CPGs. Therefore, an evidence-based method should be used, and reporting the full texts according to AGREE II checklists for the further TCM CPGs development to ensure the translation of evidence into practice.

[The development of a rapid loop-mediated indirect PCR method for detection and differentiation of highly and lowly pathogenic porcine reproductive and respiratory syndrome virus].

The aim of this study is to establish the method of loop-mediated indirect PCR assay for detection of Reproductive and Respiratory Syndrome Virus (PRRSV) infection and differentiation of highly pathogenic PRRSV (HP-PRRSV) and lowly pathogenic PRRSV (LP-PRRSV). Based on the alignments of ORF2 gene sequences and ORFla gene sequences of PRRSV Chinese isolates deposited in GenBank, two pairs of specific probes were designed and labeled to both ends of the soybean Lectin gene fragment by PCR, respectively. The probe-labeled soybean Lectin genes were used to be reporter genes for detection and differentiation of PRRSV. After one round strand displacement reaction, the reporter genes were amplified by reverse PCR. The specific PCR products were 193bp, 355bp for HP-PRRSV and 193bp, 442bp for LP-PRRSV, respectively. The method could detect 5. 6 TCID50/mL LP-PRRSV RNA and 18 TCIDs0/ mL HP-PRRSV RNA, and co-infection did not affect detection sensitivity. No amplification was observed with other porcine originated pathogens including CSFV, PPV, PRV, PCV2, ETEC and Haemophilus parasui. Twenty clinical samples were used for comparative testing with conventional PCR. Fourteen samples were found positive for PRRSV by the loop-mediated indirect PCR, of which 4 were LP-PRRSV, 9 HP-PRRSV and 1 LP/HP-PRRSV co-infection, consistent with the conventional PCR test results. In conclusion, the loop-mediated indirect PCR is a simple, rapid, sensitive and specific etiologic diagnosis tool, and suitable for the differential diagnosis of HP/LP-PRRSV, especially for identification of mixed infection of HP/LP-PRRSV.