Photosynthetic apparatus efficiency, phenolic acid profiling and pattern of chosen phytohormones in pseudometallophyte Alyssum montanum

The present study investigated the response of non-metallicolous (NM) and metallicolous (M) Alyssum montanum shoots cultured in vitro on a medium supplemented simultaneously with heavy metals (HMs) to identify mechanisms involved in alleviating metal-induced damage. Plant status in respect to photosynthetic apparatus efficiency was determined and linked with changes in biochemical composition of shoots, namely phenolic acids’ and stress-related phytohormones. Results showed the considerable inter-ecotype differences in (1) the photosynthetic pigments’ amount, (2) the functioning of membrane electron transporters as well as (3) the linear and alternative electron transport pathways, whose lower values were reported in NM than in M HM-treated culture. Photosynthetic apparatus protection in M specimens was assured by the activation of cinnamic acid synthesis (by phenylalanine ammonia lyase) and its further transformations to benzoic acid derivatives with high ability to counteract oxidative stress, that was accompanied by the overexpression of jasmonic acid stimulating antioxidant machinery. In turn, detrimental HM effects on NM shoots could result from the diminution of most phenolics’ accumulation, and only the content of coumarate (produced by bifunctional phenylalanine/tyrosine ammonia lyase) and rosmarinic acid increased. All these together with an enhanced concentration of abscisic acid might suggest that NM strategy to cope with HMs is based mostly on a restriction of metal movement with transpiration flow and their limited distribution in leaves. Summarizing, our findings for the first time point out the physiological and metabolic adaptation of pseudometallophyte A. montanum to adverse conditions.

Impact of the Peptide WMR-K on Dual-Species Biofilm Candida albicans/Klebsiella pneumoniae and on the Untargeted Metabolomic Profile

In recent years, the scientific community has focused on the development of new antibiotics to address the difficulties linked to biofilm-forming microorganisms and drug-resistant infections. In this respect, synthetic antimicrobial peptides (AMPs) are particularly regarded for their therapeutic potential against a broad spectrum of pathogens. In this work, the antimicrobial and antibiofilm activities of the peptide WMR-K towards single and dual species cultures of Candida albicans and Klebsiella pneumoniae were investigated. We found minimum inhibitory concentration (MIC) values for WMR-K of 10 µM for K. pneumoniae and of 200 µM for C. albicans. Furthermore, sub-MIC concentrations of peptide showed an in vitro inhibition of biofilm formation of mono and polymicrobial systems and also a good biofilm eradication even if higher concentrations of it are needed. In order to provide additional evidence for the effect of the examined peptide, a study of changes in extracellular metabolites excreted and/or uptaken from the culture medium (metabolomic footprinting) in the poly-microbial association of C. albicans and K. pneumoniae in presence and absence of WMR-K was performed. Comparing to the untreated dual species biofilm culture, the metabolomic profile of the WMR-K treated culture appears significantly altered. The differentially expressed compounds are mainly related to the primary metabolic pathways, including amino acids, trehalose, pyruvic acid, glycerol and vitamin B6.

Impact of Methoprene Against the Egg Biochemistry of Rice Moth, Corcyra cephalonica Staint. (Lepidoptera: Pyralidae)

: Exposure of first instar larvae of rice moth, Corcyra cephalonica to the sublethal concentrations i.e. 4, 8 and 12 ppm of methoprene caused dose-dependent alterations in the biochemical constituents of the eggs (laid within 24 h of mating by different crosses involving one or the other or both sexes emerged from treated culture). Such biochemical changes in eggs might lead to impairment of embyonic and post-embryonic growth and development of this pest, and hence, evolution of a new generation of this lepidopterous pest for the eventual establishment on stored cereals and cereal commodities can be considerably restricted.

The Anti-Cancer Property of Mumie as Natural Product on Human Cervical Cancer Cell Line (HeLa)

Mumie is a natural component found in some mountains, such as the Himalayas, as well as in some mountainous of Iran. It contains of humic and phenolic compounds that have antioxidant and anti-cancer properties. Therefore, in this study, anti-cancer and antioxidant properties of mumie were examined on Human Cervical Cancer Cell Line (HeLa). HeLa cells and normal fibroblasts (NIH) were cultured in DMEM/F12 with mumie at concentrations of 0, 100, 200, 300, 400, 500 and 1000 µg/ml for 24 and 48 h. The bioviability of these cells were evaluated using MTT assay. Chromatin condensation and apoptosis of these cells were examined using acridine orange and aniline blue staining respectively. Antioxidant property of mumie on NIH cells was evaluated by 10 mM H2O2 and neutral red test. MTT assay revealed bioviability of HeLa cells decreased but chromatin condensation increased in concentration of 100 μg/ml mumie treated culture. Apoptosis of the HeLa cells were observed in 100 μg/ml mumie treated culture. Mumie did not affect the bioviability, chromatin condensation and apoptosis of NIH cells but 500 and 1000 μg/ml concentrations were toxic and induced cell death. The cell cultures in different concentrations of mumie after 24and 48 h showed the similar results. NIH cells bioviability increased in 500 and 1000 μg/ml concentrations of co-culture of H2O2 and mumie that confirmed the antioxidant property. It concluded that even low concentrations of mumie could destroy HeLa cells without any side effect on normal cells. Therefore, it can be used for cervical cancer treatment but further research is needed.

Probing the Mode of Antibacterial Action of Silver Nanoparticles Synthesized by Laser Ablation in Water: What Fluorescence and AFM Data Tell Us

We aim to elucidate the mode of antibacterial action of the laser-synthesized silver colloid against Escherichia coli. Membrane integrity was studied by flow cytometry, while the strain viability of the treated culture was determined by plating. The spectrofluorometry was used to obtain the time development of the reactive oxygen species (ROS) inside the nanoparticle-treated bacterial cells. An integrated atomic force and bright-field/fluorescence microscopy system enabled the study of the cell morphology, Young modulus, viability, and integrity before and during the treatment. Upon lethal treatment, not all bacterial cells were shown to be permeabilized and have mostly kept their morphology with an indication of cell lysis. Young modulus of untreated cells was shown to be distinctly bimodal, with randomly distributed softer parts, while treated cells exhibited exponential softening of the stiffer parts in time. Silver nanoparticles and bacteria have shown a masking effect on the raw fluorescence signal through absorbance and scattering. The contribution of cellular ROS in the total fluorescence signal was resolved and it was proven that the ROS level inside the lethally treated cells is not significant. It was found that the laser-synthesized silver nanoparticles mode of antibacterial action includes reduction of the cell’s Young modulus in time and subsequently the cell leakage.

Antifungal activity of eugenol on Cryptococcus neoformans biological activity and Cxt1p gene expression

Background and Purpose: The present study was targeted toward investigating the effects of eugenol on Cryptococcus neoformans biological activity and Cxt1p gene expression. Materials and Methods: For the purpose of the study, the growth, urease, synergism activity, and disk diffusion of C. neoformans were assessed in eugenol-treated culture. The minimum inhibitory concentration (MIC) was determined by the Clinical and Laboratory Standards Institute M27-A3 method at a concentration range of 0.062-2 mg/mL. Subsequently, the expression of Cxt1p genes was studied at the MIC50 concentration of eugenol using real-time polymerase chain reaction. Results: The obtained results showed that eugenol at the concentrations of 125 and 500 μg/mL resulted in 50% and 100% growth inhibition in C. neoformans, respectively. In terms of urease activity, the results showed that the addition of MIC50 of eugenol and fluconazole to urea medium reduced urease activity in C. neoformans. In the culture treated with eugenol, the inhibition zone of antifungal drugs, namely amphotericin B, itraconazole, and fluconazole, was increased to 36±0.002, 22±0.001, and 12±0.002 mm, respectively. The expression levels of Cxt1p in the eugenol-treated, fluconazole-treated, and non-treated samples were estimated at 46%, 58%, and 100%, respectively. Conclusion: The findings of the current study revealed that eugenol could cause C. neoformans growth inhibition and reduce Cxt1p expression in this species. As the results indicated, the susceptibility of C. neoformans to fluconazole was increased when combined with eugenol.

5-Iodo-4-thio-2′-Deoxyuridine as a Sensitizer of X-ray Induced Cancer Cell Killing

Nucleosides, especially pyrimidines modified in the C5-position, can act as radiosensitizers via a mechanism that involves their enzymatic triphosphorylation, incorporation into DNA, and a subsequent dissociative electron attachment (DEA) process. In this paper, we report 5-iodo-4-thio-2′-deoxyuridine (ISdU) as a compound that can effectively lead to ionizing radiation (IR)-induced cellular death, which is proven by a clonogenic assay. The test revealed that the survival of cells, pre-treated with 10 or 100 µM solution of ISdU and exposed to 0.5 Gy of IR, was reduced from 78.4% (for non-treated culture) to 67.7% and to 59.8%, respectively. For a somewhat higher dose of 1 Gy, the surviving fraction was reduced from 68.2% to 54.9% and to 40.8% for incubation with 10 or 100 µM ISdU, respectively. The cytometric analysis of histone H2A.X phosphorylation showed that the radiosensitizing effect of ISdU was associated, at least in part, with the formation of double-strand breaks. Moreover, the cytotoxic test against the MCF-7 breast cancer cell line and human dermal fibroblasts (HDFa line) confirmed low cytotoxic activity of ISdU. Based on the results of steady state radiolysis of ISdU with a dose of 140 Gy and quantum chemical calculations explaining the origin of the MS detected radioproducts, the molecular mechanism of sensitization by ISdU was proposed. In conclusion, we found ISdU to be a potential radiosensitizer that could improve anticancer radiotherapy.

Inmunización a Tripanosoma cruzi con antígenos tratados con detergentes

C 3H/ Anf mice were immunized with Lubrol or cholate- treated culture forms of the Tuluhuén strain of Trypanosoma cruzi and subsequently challenged with the homologous bloodstream forms. The equivalent of 1x108 – 2x108 detergent-treated culture forms were injected intraperitoneally, intramuscularly or subcutaneously. The mice were challenged intraperitoneally with 1x105 – 2x105 bloddstream forms equivalent to 100-200LD50 administered 21 or 42 days after immunization. The effects of immunization were measured by recording survival times, noting blood and tissue parasitemias, and by attempting to recover parasites from the challenged mice in Rhesus monkey kidney tissue cell cultures and in irradiated mice.