Synthesis of biologically stable gold nanoparticles using imidazolium-based amino acid ionic liquids

A novel double-step reduction procedure for the synthesis of gold nanoparticles (AuNPs) using amino acid ionic liquids has been employed. 1-Dodecyl-3-methyl imidazolium tryptophan ([C(12)mim]Trp) and 1-ethyl-3-methyl imidazolium tryptophan ([C(2)mim]Trp) were used for this synthesis. The synthesized AuNPs were characterized by UV-vis spectroscopy, transmission electron microscopy and dynamic light scattering. The behavior of these AuNPs were also probed in a biological media. It was proven that AuNPs synthesized at [C(12)mim]Trp have more stability than AuNPs synthesized at [C(2)mim]Trp due to the longer alkyl chain of the imidazolium moiety. The solubility test shows that the resultant AuNPs have a hydrophilic nature. Finally, it was seen that due to the presence of a biomolecule, namely Trp, in the structure of AuNPs protecting shell, higher stability and biocompatibility was achieved in the biological media.     

Kit (W-sh) mice develop earlier and more severe experimental autoimmune encephalomyelitis due to absence of immune suppression

Mast cells (MCs) have been thought to play a pathogenic role in the development of autoimmune diseases, including experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis. However, an immunoregulatory function of these cells has recently been suggested. We investigated the role of MCs in EAE using the W(-sh) mouse strain, which is MC deficient. W(-sh) mice developed earlier and more severe clinical and pathological disease with extensive demyelination and inflammation in the CNS. The inflammatory cells were mainly composed of CD4(+) T cells, monocyte/macrophages, neutrophils, and dendritic cells. Compared with wild-type mice, MC-deficient mice exhibited an increased level of MCP-1/CCR2 and CD44 expression on CD4(+) T cells in addition to decreased production of regulatory T cells, IL-4, IL-5, IL-27, and IL-10. We also found that levels of IL-17, IFN-γ, and GM-CSF were significantly increased in peripheral lymphocytes from immunized W(-sh) mice compared with those in peripheral lymphocytes from wild-type mice. Reconstitution of W(-sh) mice downregulated susceptibility to EAE, which correlated with MC recruitment and regulatory T cell activation in the CNS. These findings indicate that responsiveness is not required in the pathogenesis of inflammatory demyelination in the CNS and that, in the absence of MCs, increased MCP-1, CCR2, IL-17, IFN-γ, CD44, and other inflammatory molecules may be responsible for increased severity of EAE.     

A new species of Scorzonera (Asteraceae) from Khorasan, Iran

Scorzonera joharchii sp. nov. is described from the Khorasan, east of Birjand, Iran. It is similar to S. tuberosa from which it mainly differs in its tomentose indumentum, longer pappus and villous and longer achenes.     

Effect of nutrition on growth and virulence of the entomopathogenic fungus Beauveria bassiana

Three isolates of the entomopathogen Beauveria bassiana along with one strain of Metarhizium anisopliae were cultured on seven media with different carbon/nitrogen (C/N) ratios. The effect of nutrition on virulence of the isolates was evaluated via measurement of colony growth, spore yield, germination speed, conidial C/N ratio and Pr1 (a serine protease) activity. 'Osmotic stress' medium produced the lowest colony growth with low numbers of conidia in all isolates. However, these conidia showed a high germination rate and virulence. However, conidial Pr1 activity was low in some isolates. In most but not in all cases conidia from 1% yeast extract, 2% peptone and low (10 : 1) C/N medium had higher Pr1 activity compared with conidia from other media. However, in some instances we could not conclude that there was a relationship among germination rate, conidial Pr1 activity and virulence. C/N ratio of conidia was statistically different among various media and fungal isolates. Conidia with lower C/N ratio generally produced lower LT(50) (lowest median lethal time) values (more virulent). Insect-passaged conidia from different media had lower C/N ratio compared with similar conidia from artificial cultures. Therefore, they should be more virulent than in vitro produced conidia. As germination rate, conidial Pr1 activity and C/N ratio are independent of host, it seems that host-related determinants such as insect cuticle and physiology and environmental conditions may influence host susceptibility and therefore fungal isolate virulence towards host insects.     

Design and Synthesis of Novel Cytotoxic Indole‐Thiosemicarbazone Derivatives: Biological Evaluation and Docking Study

In this work, two novel series of indole‐thiosemicarbazone derivatives were designed, synthesized, and evaluated for their cytotoxic activity against MCF‐7, A‐549, and Hep‐G2 cell lines in comparison to etoposide and colchicine as the reference drugs. Generally, the synthesized compounds showed better cytotoxicity towards A‐549 and Hep‐G2 than MCF‐7. Among them, (2E)‐2‐{[2‐(4‐chlorophenyl)‐1H‐indol‐3‐yl]methylidene}‐N‐(4‐methoxyphenyl)hydrazinecarbothioamide ( 8l ) was found to be the most potent compound against A‐549 and Hep‐G2, at least three times more potent than etoposide. The morphological analysis by the acridine orange/ethidium bromide double staining test and flow cytometry analysis indicated that compound 8l induced apoptosis in A‐549 cells. Moreover, molecular docking methodology was exploited to elucidate the details of molecular interactions of the studied compounds with putative targets.     

Simultaneous electrochemical determination of l-cysteine and l-cysteine disulfide at carbon ionic liquid electrode

A linear sweep voltammetric method is used for direct simultaneous determination of l-cysteine and l-cysteine disulfide (cystine) based on carbon ionic liquid electrode. With carbon ionic liquid electrode as a high performance electrode, two oxidation peaks for l-cysteine (0.62 V) and l-cysteine disulfide (1.3 V) were observed with a significant separation of about 680 mV (vs. Ag/AgCl) in phosphate buffer solution (pH 6.0). The linear ranges were obtained as 1.0–450 and 5.0–700 μM and detection limits were estimated to be 0.298 and 4.258 μM for l-cysteine and l-cysteine disulfide, respectively. This composite electrode was applied for simultaneous determination of l-cysteine and l-cysteine disulfide in two real samples, artificial urine and nutrient broth. Satisfactory results were obtained which clearly indicate the applicability of the proposed electrode for simultaneous determination of these compounds in complex matrices.     

Virulence patterns of barley yellow rust and effective resistance genes to Puccinia striiformis in three parts of Iran

Stripe rust of barley (Hordeum vulgare L.), caused by Puccinia striiformis f. sp. hordei, is a serious problem of barley production in many parts of the world. Monitoring of the pathogen virulence factors and their changes provides basic information for development of an early warning system to breeders and researchers. To monitor the regular virulence changes, trap nurseries comprising of 12 barley differential sets were planted at different parts of Iran in six consecutive years 2007–2012. When the infection and severity under natural infection on susceptible cultivar Afzal as the check was high, then the response of each line was assessed using modified Cobbs scale. Results revealed that no virulence was observed on plants with resistance genes rpsEm1, rpsEm2, rpsHF, Rps4, rpsVa1, rpsVa2 and rpsAst. Therefore, these genes were considered effective genes and can be used to pyramid with those for race-non-specific resistance genes to achieve more durable and highly effective resistance to stripe rust. The plants with the resistance genes rps2, Rps1.b, Rps3 and rpsI5 showed susceptible reaction and virulence was observed on them, thus their resistance genes were considered ineffective.     

Efficacy of Beauveria bassiana (Blas.) Vuill. against cabbage aphid Brevicoryne brassicae L. (Hem.: Aphididae) in laboratory condition

In order to replace the conventional chemical pesticides, extensive researches have been done on entomopathogenic fungi. Entomopathogenic fungus Beauveria bassiana is an important biocontrol agent against major economic pests and is being employed in Integrated pest management (IPM) along with synthetic pesticides. Cabbage aphid Brevicoryne brassicae L. is one of the important pests of Brassicaceae family. Therefore, in this research, the virulence isolate of B. brassicae (IRAN 429C) was investigated on adults of cabbage aphid under laboratory conditions. The experiments were conducted at 25 ± 2 °C, 60 ± 10 R. H. and a photoperiod of 16:8 (L: D). After preliminary experiments, the adult aphids were treated with fungal concentrations of 1 × 10³ to 1 × 10⁷ spores/ml. Probit analysis was conducted to calculate LC₅₀ and LC₉₅ values for the isolate. Positive correlation was observed between concentrations and pest mortality. LC₅₀ and LC₉₅ values calculated for IRAN 429C isolate are 2.04 × 10⁵ and 1.82 × 10⁸, respectively. The mortality was counted one day after the treatment and then continued for 14 days. Cumulative mortality for 14 days after treatment varied from 54% for IRAN 429C at low concentration (10³ conidia/ml) to 83% at high concentration (10⁷ conidia/ml). The lowest LT₅₀ was obtained at 7.67 days for IRAN 429C isolate at concentration 1 × 10⁷ spore/ml. According to the insecticidal activity of mentioned fungi on cabbage aphid, it can be used in biocontrol programmes of B. brassicae.     

Effect of yellow rust on yield components of barley cultivars with race-specific and slow rusting resistance to yellow rust

Yellow rust caused by Puccinia striiformis f. sp. hordei is an important disease of barley (Hordeum vulgare L.) in some parts of the world. We compared the effectiveness of different types of resistance in field plots at Ardabil Agricultural Research Station (Iran) during 2010–2011. Yield components along with slow rusting parameters including final rust severity (FRS), apparent infection rate (r), relative area under disease progress curve (rAUDPC) and coefficient of infection (CI) were evaluated for 25 barley cultivars. In all, two barley cultivars with race-specific resistance, 19 cultivars with different levels of slow rusting resistance and four susceptible cultivars were included in two experiments with and without fungicide protection under high disease pressure. Barley cultivars with slow rusting resistance displayed a range of severity responses indicating phenotypic diversity. Mean thousand kernels weight (TKW) losses for susceptible, race-specific and slow rusting genotypes were 31, 3 and 12%, respectively, and mean kernels per spike (KPS) losses for susceptible, race-specific and slow rusting genotypes were 19, 0.2 and 8%, respectively. Correlation coefficient of mean TKW and KPS losses with epidemiological parameters; rAUDPC, r, CI and FRS were highly significant. Slow rusting cultivars with low values of different parameters as well as genotypes with low yield component losses despite moderate disease levels were identified. Such genotypes can be used for breeding barely genotypes with high levels of resistance and negligible yield losses.