Antivirulence effects of cell-free culture supernatant of endophytic bacteria against grapevine crown gall agent, Agrobacterium tumefaciens, and induction of defense responses in plantlets via intact bacterial cells.

BACKGROUND: Crown gall disease caused by Agrobacterium tumefaciens is a very destructive affliction that affects grapevines. Endophytic bacteria have been discovered to control plant diseases via the use of several mechanisms. This research examined the potential for controlling crown gall by three endophytic bacteria that were previously isolated from healthy cultivated and wild grapevines including Pseudomonas kilonensis Ba35, Pseudomonas chlororaphis Ba47, and Serratia liquefaciens Ou55. RESULT: At various degrees, three endophytic bacteria suppressed the populations of A. tumefaciens Gh1 and greatly decreased the symptoms of crown gall. Furthermore, biofilm production and motility behaviors of A. tumefaciens Gh1were greatly inhibited by the Cell-free Culture Supernatant (CFCS) of endophytic bacteria. According to our findings, CFCS may reduce the adhesion of A. tumefaciens Gh1 cells to grapevine cv. Rashe root tissues as well as their chemotaxis motility toward the extract of the roots. When compared to the untreated control, statistical analysis showed that CFCS significantly reduced the swimming, twitching, and swarming motility of A. tumefaciens Gh1. The findings demonstrated that the endophytic bacteria effectively stimulated the production of plant defensive enzymes including superoxide dismutase (SOD), polyphenol oxidase (PPO), peroxidase (POD), phenylalanine ammonia lyase (PAL), and total soluble phenols at different time intervals in grapevine inoculated with A. tumefaciens Gh1. The Ba47 strain markedly increased the expression levels of defense genes associated with plant resistance. The up-regulation of PR1, PR2, VvACO1, and GAD1 genes in grapevine leaves indicates the activation of SA and JA pathways, which play a role in enhancing resistance to pathogen invasion. The results showed that treating grapevine with Ba47 increased antioxidant defense activities and defense-related gene expression, which reduced oxidative damage caused by A. tumefaciens and decreased the incidence of crown gall disease. CONCLUSION: This is the first study on how A. tumefaciens, the grapevine crown gall agent, is affected by CFCS generated by endophytic bacteria in terms of growth and virulence features. To create safer plant disease management techniques, knowledge of the biocontrol processes mediated by CFCS during microbial interactions is crucial.

Safety and efficacy of the FAKHRAVAC compared with BBIBP-Corv2 against SARS-CoV-2 in adults: a non-inferiority multi-center trial.

BACKGROUND: We compared Fakhravac and BBIBP-Corv2 vaccines in a phase III trial. METHOD: We conducted a multicenter, parallel-group, active-control, non-inferiority clinical trial with pragmatic considerations assessing the safety and efficacy of Fakhravac and BBIBP-Corv2 vaccines. We started with two randomized double-blind arms and added two non-randomized open-label arms (based on participant preference) because of slow recruitment. The adult population received 0.5 ml (10 µg per dose) intramuscular injections of Fakhravac or BBIBP-Corv-2 vaccines 21 days apart. The primary outcome was the occurrence of PCR-positive symptomatic Covid-19 disease 14 days or more after the second injection. A 10% non-inferiority margin to the reported 72.8% efficacy of BBIBP-Corv2 was assumed. Cox proportional hazard modeling was used to estimate hazard ratios and their 95% confidence intervals. RESULT: We enrolled 24,056 adults in four groups (randomized-Fakhravac: 824, randomized-BBIBP-Corv2: 832; Non-randomized-Fakhravac: 19,429, Non-randomized-BBIBP-Corv2: 2971). All observed local and systemic adverse reactions were generally self-limited and resolved completely. We observed similar Serious Adverse Event (SAE) rates in the BBIBP-Corv2 (2.57, 95% CI 1.33-4.49) and Fakhravac (2.25, 95% CI 1.72-2.89) groups; none of which were related to the vaccines received. We recorded 9815 Medically Attendant Adverse Events (MAAE), 736 of which were categorized as somehow related. The rate of related MAAE in the Fakhravac was similar to the BBIBP-Corv2 groups (0.31 and 0.26 per 1000 person-day) in the randomized and considerably higher (0.24 and 0.07 per 1000 person-day) in the non-randomized arms. We observed 129 (35% of the 365 required by target sample size) events of PCR + symptomatic Covid-19 during four months of active follow-up in the randomized arm, demonstrating that those receiving the Fakhravac vaccine were significantly less likely (HR = 0.69; 95% CI 0.49-0.98) to be diagnosed with PCR + symptomatic Covid-19 compared with those receiving BBIBP-Corv2 vaccine. After adjusting for type I error using the O'Brien Fleming method, the Fakhravac vaccine was non-inferior to the BBIBP-Corv2 (assuming a 10% non-inferiority margin to the reported 72.8% BBIBP-Corv2 vaccine efficacy; HR < 1.35) (One-way test: HR = 0.66; 99.8% CI 0.38-1.15). In the non-randomized arm, the results were inconclusive (HR = 1.23; 95% CI 0.96-1.61). We observed 5 cases of hospitalized Covid-19 in the randomized arm, none of which occurred in the Fakhravac vaccine group. Those receiving the Fakhravac vaccine were four times less likely to go to the hospital because of a Covid-19 diagnosis (HR = 0.24; 95% CI 0.10-0.60). The vaccine efficacy of the Fakhravac vaccine is estimated to be 81.5% (95% CI 81-82.4%). CONCLUSION: Fakhravac inactivated SARS-CoV-2 vaccine has comparable safety and efficacy to the BBIBP-Corv2 vaccine. Trial registration This study was registered with the Iranian Registry of Clinical Trials ( www.irct.ir : IRCT20210206050259N3).

Strawberry crinkle (SCV) and Strawberry mottle (SMoV) viruses affect yield and physio-biochemical responses of three strawberry cultivars under different seasonal conditions.

BACKGROUND: The current study was performed to evaluate the impact of Strawberry crinkle virus (SCV) and Strawberry mottle virus (SMoV) viruses, in single and mixed infections, on the yield and physio-biochemical traits of strawberry plants with different genetic backgrounds. Accordingly, the virus-free plantlets were produced via meristem culture and were then transplanted in a research field in different seasons. METHODS AND RESULTS: The results indicated that genetic background clearly affects the responses of the strawberry plants to the viral infection. In addition, considering the effects of changing environmental factors, different seasons had significant influences on the strawberry responses to the virus infection. The results indicated that the components indicating destructive effects were significantly higher during the summer season. Reverse transcription-polymerase chain reaction using viral specific primers revealed 345 and 461 bp fragments for SCV and SMoV viruses, respectively, where all plants were positive for studied viruses. The comparison between the influence of SCV and SMoV viruses on the host plants indicated that SCV caused more damaging effects on the strawberry fruit yield and physio-biochemical traits. Simultaneous infection with SCV and SMoV severely impacted the strawberry plants compared with the effect of each virus individually. CONCLUSION: It is recommended to keep the temperature of the greenhouses producing strawberry at the cooler levels to prevent the spreading of the aphid-transmitted viruses.

Uncommon Terpenoids from Salvia Species: Chemistry, Biosynthesis and Biological Activities.

The search for new bioactive compounds from plant sources has been and continues to be one of the most important fields of research in drug discovery. However, Natural Products research has continuously evolved, and more and more has gained a multidisciplinary character. Despite new developments of methodologies and concepts, one intriguing aspect still persists, i.e., different species belonging to the same genus can produce different secondary metabolites, whereas taxonomically different genera can produce the same compounds. The genus Salvia L. (Family Lamiaceae) comprises myriad distinct medicinal herbs used in traditional medicine worldwide that show different pharmacological activities due to the presence of a variety of interesting specialized metabolites, including mono-, sesqui-, di-, sester-, tri-, tetra-, and higher terpenoids as well as phenylpropanoids, phenolic acid derivatives, lignans, flavonoids, and alkaloids. We herein summarize the research progress on some uncommon terpenoids, isolated from members of the genus Salvia, which are well recognized for their potential pharmacological activities. This review also provides a current knowledge on the biosynthesis and occurrence of some interesting phytochemicals from Salvia species, viz. C23-terpenoids, sesterterpenoids (C25), dammarane triterpenoids (C30), and uncommon triterpenoids (C20+C10). The study was carried out by searching various scientific databases, including Elsevier, ACS publications, Taylor and Francis, Wiley Online Library, MDPI, Springer, Thieme, and ProQuest. Therefore, 106 uncommon terpenoids were identified and summarized. Some of these compounds possessed a variety of pharmacological properties, such as antibacterial, antiviral, antiparasitic, cytotoxic and tubulin tyrosine ligase inhibitory activities. Due to the lack of pharmacological information for the presented compounds gathered from previous studies, biological investigation of these compounds should be reinvestigated.

Superoxide dismutase (SOD) as a selection criterion for triticale grain yield under drought stress: a comprehensive study on genomics and expression profiling, bioinformatics, heritability, and phenotypic variability.

BACKGROUND: The main objectives of this study were to find the possible structural association between the activity of enzymatic antioxidants and the grain yield of triticale plants as well as identifying the genotypic variability which might be effective on this association. Accordingly, expression levels of superoxide dismutase (SOD) isozymes (Mn-SOD, Cu/Zn-SOD, and Fe-SOD) were appraised to distinguish any possible relationship between SOD expression and drought resistance of triticale. A novel analytical method for distinguishing elite genotypes based on measured features was proposed. Additionally, a new programing based on SAS-language (IML) was introduced to estimate the genetic parameters rooted from combined ANOVA model (linear mixed model), which is capable of being used in any field study other than the current one. METHODS: Thirty genotypes of triticale were studied under normal and drought stress conditions during 6 years (three different locations). Accordingly, based on the results of genetic variability, heatmap analysis, biplot graph, and clustering technique, two genotypes with the highest genetic distance were selected to appraise the differential expression profiling of three SOD isozyme in shoot and root organs. RESULTS: Field experiments and bioinformatics results showed that superoxide dismutase (SOD) was the most influential antioxidant in resistance of triticale to drought stress; therefore, it could be used as an indirect selection index in early stages to distinguish resistant genotypes to drought stress. Additionally, Mn-SOD and Fe-SOD showed roughly similar expression levels for both genotypes under drought stress. However, Cu/Zn-SOD expression level was higher in root and shoot of the tolerant genotype than the susceptible genotype. CONCLUSION: Heatmap analysis that is applied for the first time to screen suitable genotypes, showed to be highly capable of distinguishing elite genotypes and pointing out the proper features for selection criteria. Bioinformatics results indicated that SOD is more important than other enzymatic antioxidant for being considered as selection criteria or candidate gene for transgenic purposes. Based on expressional results, Mn-SOD announced as a general isozyme that is probably highly expressed in most of the species, while, Cu/Zn-SOD was introduced as a genotype specific isozyme that is likely more expressed in tolerant genotypes.

Receding Phase and Rebound Behavior for Drop Impact onto an Ultrathin Film.

Experimentally, the recoil phase leading to rebound behavior for drop impact onto ultrathin oil-covered solid surfaces was studied. It was found that the oil film can rupture during the impact process when the contact angle between the drop liquid and substrate is smaller than 90°. Due to such rupture, the substrate wettability of the substrate can affect the behavior of the drop impact. The rupture of the oil film can be promoted by an increase in impact Weber number (We) and a decrease in the film viscosity and thickness. The effect of We, oil viscosity, and film thickness on the rebound behavior of the drop was also investigated. For low-viscous oil films (5 cSt), it was shown that the smooth and circular edge of the liquid lamella is the key parameter affecting the level of rebound. The smooth rim of the lamella can cause an elongated rebound, while a lamella with a jagged rim will result in a stout rebound. For the impact cases onto oil films with medium and high viscosity, the effects of the film viscosity become more important; the rebound type can be suppressed due to the viscous dispassion. We have also shown that silicone oil can cloak the daughter drops generated in the rebound process for the first time. Due to the existence of the oil, the daughter drops do not merge even when they make contact in the air.

Neutrophil-to-Lymphocyte Ratio as a Poor Prognostic Factor in Iranian COVID-19 Patients.

BACKGROUND: We aimed to accumulate evidence that suggests the potential role of neutrophil-to-lymphocyte ratio (NLR) in determining the prognostic factor for COVID-19 patients. METHODS: A cohort of COVID-19 hospitalized patients at the Ilam University of Medical Sciences was analyzed. Logistic regression models were performed to identify the potential role of NLR in determining the prognostic factor for COVID-19 patients. RESULTS: The total number of in-hospital mortality was 43/328 (13.1%). Multivariate analysis identified that there was a 26% higher risk of in-hospital death for each unit increase in NLR (Odds ratio [OR] = 1.08; 95% confidence interval [95% CI], 1.01 to 1.14; p = 0.0147). Multivariate analysis identified that there was an 8% higher risk of in-hospital death for each unit increase in NLR (Odds ratio [OR] = 1.08; 95% confidence interval [95% CI], 1.01 to 1.14; p = 0.0147). Compared with patients in the NLR < 5 group, the NLR of patients in the NLR ≥ 5 group had a 16-fold higher risk of mortality (OR = 16.04; 95% CI, 1.14 to 224.95; p = 0.0395) after adjustment for potential confounders. CONCLUSIONS: NLR is an independent risk factor of mortality COVID-19 patients.

Grape response to salinity stress and role of iron nanoparticle and potassium silicate to mitigate salt induced damage under in vitro conditions.

Grape softwood cuttings of Khoshnaw cultivar were cultured using tissue-culture methods to study the effect of iron nanoparticles and potassium silicate under salinity conditions during the 2015-2016 growing season. The treatments consisted of salinity stress (0, 50, and 100 mM NaCl), nanoparticles of iron (0, 0.08, and 0.8 ppm), and potassium silicate (0, 1, 2 mM). The results also showed that the application of iron nanoparticles and potassium silicate significantly increased the total protein content and reduced proline, enzymatic antioxidant activity and hydrogen peroxide. Salinity stress reduced membrane stability index while increased malondialdehyde content. Increase of membrane stability index and reduction of malondialdehyde content were obtained for 2 mM potassium silicate and 0.8 ppm iron nanoparticle. Iron and potassium silicate were shown to lower the sodium content and increase the potassium content under salinity-stress conditions. The highest ratio of sodium to potassium was observed in plants under salinity conditions (100 mM) treated with neither iron nanoparticles nor potassium silicate; conversely, the lowest ratio was achieved in plants treated with both 0.8 ppm iron nanoparticles with 1 mM and 2 mM potassium silicate under non-stress conditions. These results indicate that the application of micronutrients in stressful conditions is a suitable method to compensate for the negative effects of salinity stress. Tissue culture in this study was shown to be an economically efficient and applicable technique for producing grape softwood cuttings to be used in experiments.

Phytochemical composition and in vitro antioxidant potential of Cynodon dactylon leaf and rhizome extracts as affected by drying methods and temperatures.

The effect of five drying methods including shade drying (SHD), solar drying (SOD), and oven drying at 30 (OD30), 40 (OD40) and 50 °C (OD50) on the phytochemical composition and antioxidant potential of C. dactylon leaf and rhizome was assessed. Among drying methods, OD50 resulted in the shortest drying time (18.3 and 12 h for rhizome and leaf, respectively), when compared with SHD and SOD. Based on GC-MS analyses, 15 and 17 constituents were identified in leaf and rhizome extracts, respectively, accounting for ~ 99% of all components. Fatty acids (palmitic acid and linoleic acid) along with their methyl esters (ethyl palmitate, ethyl linoleate and ethyl oleate) and other derivatives (dihomo-γ-linoleic acid) were the main identified constituents shortly after drying procedures; however, other components such as 5-hydroxymethylfurfural, maltol, retinol and phytol were also traced. Some of C. dactylon phytochemicals including 5-hydroxymethylfurfural and ethyl linoleate were sensitive to high drying temperatures. Besides, higher drying temperatures lead to the production or increasing the level of substances such as 2,3-dihydrobenzofuran, tricyclopentadeca-3,7-dien and 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one and diacetin. Based on the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay, the IC50 values were generally higher (significance level of 0.05) for oven-dried rhizome compared with shade-dried leaves and rhizomes that quenched more than 84% of the DPPH at the concentration of 400 mg/ml (IC50 59.12). Our findings suggest that OD30 is a versatile drying method not only to reduce drying time but also to preserve the main phytochemicals and antioxidant activity of C. dactylon during dehydration.