Inhibitory activity of Iranian plant extracts on growth and biofilm formation by Pseudomonas aeruginosa

Aims: Pseudomonas aeruginosa is a drug resistance opportunistic bacterium. Biofilm formation is key factor for survivalof P. aeruginosa in various environments. Polysaccharides may be involved in biofilm formation. The purpose of thisstudy was to evaluate antimicrobial and anti-biofilm activities of seven plant extracts with known alpha-glucosidaseinhibitory activities on different strains of P. aeruginosa.Methodology and results: Plants were extracted with methanol by the maceration method. Antimicrobial activities weredetermined by agar dilution and by growth yield as measured by OD560nm of the Luria Bertani broth (LB) culture with orwithout extracts. In agar dilution method, extracts of Quercus infectoria inhibited the growth of all, while Myrtuscommunis extract inhibited the growth of 3 out of 8 bacterial strains with minimum inhibitory concentration (MIC) of 1000μg/mL. All extracts significantly (p≤0.003) reduced growth rate of the bacteria in comparison with the control withoutextracts in LB broth at sub-MIC concentrations (500 μg/mL). All plant extracts significantly (p≤0.003) reduced biofilmformation compared to the controls. Glycyrrhiza glabra and Q. infectoria had the highest anti-biofilm activities. Nocorrelation between the alpha-glucosidase inhibitory activity with growth or the intensity of biofilm formation was found.Conclusion, significance and impact of study: Extracts of Q. infectoria and M. communis had the most antimicrobial,while Q. infectoria and G. glabra had the highest anti-biofilm activities. All plant extracts had anti-biofilm activities withmarginal effect on growth, suggesting that the mechanisms of these activities are unrelated to static or cidal effects.Further work to understand the relation between antimicrobial and biofilm formation is needed for development of newmeans to fight the infectious caused by this bacterium in future

Acclimation to Elevated CO2 Increases Constitutive Glucosinolate Levels of Brassica Plants and Affects the Performance of Specialized Herbivores from Contrasting Feeding Guilds

Plants growing under elevated CO2 concentration may acclimate by modifying chemical traits. Most studies have focused on the effects of environmental change on plant growth and productivity. Potential effects on chemical traits involved in resistance, and the consequences of such effects on plant-insect interactions, have been largely neglected. Here, we evaluated the performance of two Brassica specialist herbivores from contrasting feeding guilds, the leaf-feeding Pieris brassicae and the phloem-feeding Brevicoryne brassicae, in response to potential CO2-mediated changes in primary and major secondary metabolites (glucosinolates) in Brassica oleracea. Plants were exposed to either ambient (400ppm) or elevated (800ppm) CO2 concentrations for 2, 6, or 10weeks. Elevated CO2 did not affect primary metabolites, but significantly increased glucosinolate content. The performance of both herbivores was significantly reduced under elevated CO2 suggesting that CO2-mediated increases in constitutive defense chemistry could benefit plants. However, plants with up-regulated defenses could also be subjected to intensified herbivory by some specialized herbivores, due to a chemically-mediated phagostimulatory effect, as documented here for P. brassicae larvae. Our results highlight the importance of understanding acclimation and responses of plants to the predicted increases in atmospheric CO2 concentrations and the concomitant effects of these responses on the chemically-mediated interactions between plants and specialized herbivore

Season-Long Volatile Emissions from Peach and Pear Trees In Situ , Overlapping Profiles, and Olfactory Attraction of an Oligophagous Fruit Moth in the Laboratory

Insect herbivores that have more than one generation per year and reproduce on different host plants are confronted with substantial seasonal variation in the volatile blends emitted by their hosts. One way to deal with such variation is to respond to a specific set of compounds common to all host plants. The oriental fruit moth Cydia (=Grapholita) molesta is a highly damaging invasive pest. The stone fruit peach (Prunus persica) is its primary host, whereas pome fruits such as pear (Pyrus communis) are considered secondary hosts. In some parts of their geographic range, moth populations switch from stone to pome fruit orchards during the growing season. Here, we tested whether this temporal switch is facilitated by female responses to plant volatiles. We collected volatiles from peach and pear trees in situ and characterized their seasonal dynamics by gas chromatography-mass spectrometry. We also assessed the effects of the natural volatile blends released by the two plant species on female attraction by using Y-tube olfactometry. Finally, we related variations in volatile emissions to female olfactory responses. Our results indicate that the seasonal host switch from peach to pear is facilitated by the changing olfactory effect of the natural volatile blends being emitted. Peach volatiles were only attractive early and mid season, whereas pear volatiles were attractive from mid to late season. Blends from the various attractive stages shared a common set of five aldehydes, which are suggested to play an essential role in female attraction to host plants. Particular attention should be given to these aldehydes when designing candidate attractants for oriental fruit moth female

The new solo-siro spun process for worsted yarns

The aim of this paper was to explore whether the properties of worsted yarns, especially hairiness, can be improved by combining the Solospun and Sirospun processes into a single Solo-Siro spun process. Wool fibres of 19 and 21 &mu;m in average diameter were spun into 40 tex yarns at different twist levels, using the conventional ring, Sirospun and Solo-Siro spun systems, respectively. These yarns were then tested for a range of properties, including hairiness, tenacity, elongation and evenness, for comparison purposes. The statistical analysis results indicate that the hairiness (S3 value) of Solo-Siro spun yarns was significantly less than that of both Sirospun and normal ring spun yarns. In addition, the tenacity of the Solo-Siro spun yarns was higher than that of the normal ring spun yarns, while changes in yarn breaking elongation were not statistically significant. For the 21 &mu;m wool, it was found that the evenness of Solo-Siro spun yarns deteriorated slightly in comparison with that of Sirospun and conventional ring spun yarns. <br /

Variation in Attraction to Host Plant Odors in an Invasive Moth Has a Genetic Basis and is Genetically Negatively Correlated with Fecundity

Lepidopteran insects are major pests of agricultural crops, and mated female moths exploit plant volatiles to locate suitable hosts for oviposition. We investigated the heritability of odor-guided host location behavior and fecundity in the cosmopolitan oriental fruit moth Grapholita (Cydia) molesta, an oligophagous herbivore that attacks fruit trees. We used a full-sib/half-sib approach to estimate the heritability and the genetic correlation between these two traits. Results document a considerable genetic basis for olfactory attraction of females (h 2 =0.37±0.17) and their fecundity (h 2 =0.32±0.13), as well as a genetic trade-off between female attraction and fecundity (r g =−0.85±0.21). These estimations were empirically corroborated by comparing two strains maintained in the laboratory for different numbers of generations. The long-term reared strain lost its olfactory discrimination ability but achieved significantly higher fecundity compared with the short-term reared strain. Our results highlight that genetic studies are relevant for understanding the evolution of odor-guided behavior in herbivore insects and for judging the promise of pest management strategies involving behavioral manipulation with plant volatile

Removal of Cadmium(II) Onto Granular Activated Carbon And Kaolinite Using Batch Adsorption

The removal of Cd(II) onto granular activated carbon (GAC) and kaolinite in singlecomponent systems has been studied using batch adsorption. Batch adsorption studied werecarried out under various amount of GAC and Kaolinite, Cd(II) ion concentration, pH andcontact time. The experimental data was analyzed by Langmuir, Freundlich and Redlich-Peterson isotherms. The equilibrium adsorption capacity of Cd(II) was determined fromLangmuir isotherm equation and found to be 3.002 mg/g for GAC and 1.837 mg/g forkaolinite. Pore diffusion model for batch adsorption is used to predict the concentrationdecaycurve for adsorption of Cd(II) onto GAC and kaolinite

A non-APOE polygenic risk score for Alzheimer's disease is associated with CSF neurofilament light in a representative sample of cognitively unimpaired 70-year-olds

The effect of Alzheimer's disease (AD) polygenic risk scores (PRSs) on amyloid and tau pathophysiology and neurodegeneration in cognitively unimpaired older adults is not known in detail. This study aims to investigate non-APOE AD-PRS and APOE ε4 in relation to AD pathophysiology evaluated by cerebrospinal fluid (CSF) biomarkers in a population-based sample of 70-year-olds. A total of 303 dementia-free individuals from the Gothenburg H70 Birth Cohort Studies were included. Genotyping was performed using the NeuroChip, and AD-PRSs were calculated. CSF levels of amyloid-β (Aβ42), total tau (t-tau), phosphorylated tau (p-tau), neurogranin (Ng), and neurofilament light (NfL) were measured with ELISA. Associations were found between non-APOE PRS and both NfL (p=0.001) and Aβ42 (p=0.02), and between APOE ε4 and Aβ42 (p=1e-10), t-tau (p=5e-4), and p-tau (p=0.002). Similar results were observed when only including individuals with CDR=0, except for no evidence of an association between non-APOE PRS and Aβ42. There was an interaction between non-APOE PRS and Aβ42 pathology status in relation to NfL (p=0.005); association was only present in individuals without Aβ42 pathology (p=0.0003). In relation to Aβ42, there was a borderline interaction (p=0.06) between non-APOE PRS and APOE ε4; association was present in ε4 carriers only (p=0.03). Similar results were observed in individuals with CDR=0 (n=246). In conclusion, among cognitively healthy 70-year-olds from the general population genetic risk of AD beyond the APOE locus was associated with NfL in individuals without Aβ42 pathology, and with Aβ42 in APOE ε4 carriers, suggesting these associations are driven by different mechanisms

Brassica Plant Responses to Mild Herbivore Stress Elicited by Two Specialist Insects from Different Feeding Guilds

Compensation growth and chemical defense are two components of plant defense strategy against herbivores. In this study, compensation growth and the response of primary and secondary metabolites were investigated in Brassica rapa plants subjected to infestation by two herbivores from contrasting feeding guilds, the phloem-feeding aphid Brevicoryne brassicae and the leaf-feeding caterpillar Pieris brassicae. These specialist herbivores were used at two different densities and allowed to feed for seven days on a young caged leaf. Changes in growth rates were assessed for total leaf area and bulb mass, whereas changes in primary and secondary metabolites were evaluated in young and mature leaves, roots, and bulbs. Mild stress by caterpillars on young plants enhanced mean bulb mass and elicited a contrasting regulation of aliphatic and indolic glucosinolates in the leaves. In contrast, mild stress by aphids enhanced leaf growth and increased glucosinolate concentrations in the bulb, the most important storage organ of B. rapa. A similar mild stress by either herbivore to older plants did not alter plant growth parameters or concentrations of the metabolites analyzed. In conclusion, Brassica plant growth was either maintained or enhanced under mild herbivore stress, and defense patterns differed strongly in response to herbivore type and plant development stage. These results have implications for the understanding of plasticity in plant defenses against herbivores and for the management of Brassica rapa in agroecosystems

Reproductive period and preclinical cerebrospinal fluid markers for Alzheimer disease: a 25-year study

OBJECTIVE: The aim of the study was to examine the association between reproductive period, as an indicator of endogenous estrogen, and levels of cerebrospinal fluid (CSF) biomarkers for Alzheimer disease (AD). METHODS: A population-based sample of women from Gothenburg, Sweden was followed from 1968 to 1994 (N = 75). All women had natural menopause and were free from dementia. Information on reproductive period (age at menarche to age at menopause) was obtained from interviews from 1968 to 1980. Lumbar puncture was performed from 1992 to 1994 and CSF levels of Aβ42, Aβ40, P-tau, and T-tau were measured with immunochemical methods. Linear regression models adjusted for potential confounders were used to analyze the relationship between reproductive period and CSF biomarkers for AD. RESULTS: Longer reproductive period was associated with lower levels of Aβ42 (β = -19.2, P  = 0.01), higher levels of P-tau (β = 0.03, P  = 0.01), and lower ratio of Aβ42/Aβ40 (β = -0.02, P  = 0.01), while no association was observed for T-tau (β = 0.01, P  = 0.46). In separate analyses, examining the different components of reproductive period, earlier age at menarche was associated higher levels of P-tau (β = -0.07, P  = 0.031) and lower ratio of Aβ42/Aβ40 (β = 0.05, P  = 0.021), whereas no association was observed with Aβ42 (β = 31.1, P  = 0.11) and T-tau (β = -0.001, P  = 0.98). Furthermore, no association was observed between age at menopause and CSF biomarkers for AD. CONCLUSIONS: Our findings suggest that longer exposure to endogenous estrogen may be associated with increased levels of AD biomarkers in the preclinical phase of AD. These findings, however, need to be confirmed in larger samples. / Video Summary: http://links.lww.com/MENO/A804