PVA based nanofiber containing cellulose modified with graphitic carbon nitride/nettles/trachyspermum accelerates wound healing

Today, bacterial cellulose has received a great deal of attention for its medical applications due to its unique structural properties such as high porosity, good fluid uptake, good strength, and biocompatibility. This study aimed to fabricate and study bacterial cellulose/graphitic carbon nitride/nettles/trachyspermum nanocomposite by immersion and PVA/BC/g-C₃N₄/nettles/trachyspermum nanofiber by electrospinning method as a wound dressing. The g-C₃N₄ and g-C₃N₄ solution were synthesized and then were characterized using Fourier transform infrared, X-ray diffraction, Zeta Potential, and scanning electronic microscope analyzes. Also, the antibacterial properties of the synthesized materials were proved by gram-positive and gram-negative bacteria using the minimum inhibitory concentration method. Besides, the toxicity, migration, and cell proliferation results of the synthesized materials on NIH 3T3 fibroblasts were evaluated using MTT and scratch assays and showed that the BC/PVA/g-C₃N₄/nettles/trachyspermum composite not only had no toxic effect on cells but also contributed to cell survival, cell migration, and proliferation has done. To evaluate the mechanical properties, a tensile strength test was performed on PVA/BC/g-C₃N₄/nettles/trachyspermum nanofibers, and the results showed good strength of the nanocomposite. In addition, in vivo assay, the produced nanofibers were used to evaluate wound healing, and the results showed that these nanofibers were able to accelerate the wound healing process so that after 14 days, the wound healing percentage showed 95%. Therefore, this study shows that PVA/BC/g-C₃N₄/nettles/trachyspermum nanofibers effectively inhibit bacterial growth and accelerate wound healing.     

Comparing the frequency of CD33+ pSTAT3+ myeloid-derived suppressor cells and IL-17+ lymphocytes in patients with prostate cancer and benign prostatic hyperplasia

Prostate cancer (PCa) is one of the most epidemic types of cancer in men. The tumor microenvironment (TME) of PCa is involved in the emergence of immunosuppressive factors such as myeloid-derived suppressor cells (MDSC), which regulate the immune system by several mechanisms, including interleukin (IL)-10 production. On the other hand, IL-17⁺ helper T cells (Th17) induce MDSCs and chronic inflammation in TME by producing IL-17. This study demonstrated that the frequency of CD33⁺ pSTAT3⁺ MDSC and IL-17⁺ lymphocyte as well as IL-10 messenger RNA (mRNA) expression were significantly higher in the PCa patients than in the benign prostatic hyperplasia (BPH) group. Moreover, there was no significant relationship between the frequency of CD33⁺ pSTAT3⁺ MDSC, and IL-17⁺ lymphocyte with Gleason scores in the PCa group. We suggested that the higher frequency of CD33⁺ pSTAT3⁺ MDSC and IL-17⁺ lymphocyte and the more frequent expression of IL-10 mRNA in PCa patients may play roles in tumor progression from BPH to PCa.     

Selective Divalent Cobalt Ions Detection Using Ag2O3-ZnO Nanocones by ICP-OES Method for Environmental Remediation

Here, we have synthesized Ag₂O₃-ZnO nanocones (NCs) by a wet-chemical route using reducing agents at low temperature. The structural, optical and morphological properties of Ag₂O₃-ZnO NCs were investigated by several conventional techniques such as powder XRD, XPS, FESEM, XEDS, FTIR and UV/vis. spectroscopy. The analytical parameters of prepared NCs were also calculated for a selective detection of divalent cobalt [Co(II)] prior to its determination by inductively coupled plasma-optical emission spectrometry (ICP-OES). The selectivity of NCs toward various metal ions, including Cd(II), Co(II), Cr(III), Cu(II), Fe(III), Ni(II), and Zn(II) was studied. Results of the selectivity study demonstrated that Ag₂O₃-ZnO NC phase was the most selective towards Co(II) ion. The uptake capacity for Co(II) ion was experimentally calculated to be ∼76.69 mgg⁻¹. Moreover, adsorption isotherm data provided that the adsorption process was mainly monolayer on homogeneous adsorbent surfaces of Ag₂O₃-ZnO NCs. Kinetic study revealed that the adsorption of Co(II) on Ag₂O₃-ZnO NCs phase followed the pseudo-second-order kinetic model. In addition, thermodynamic results provided that the adsorption mechanism of Co(II) ions on Ag₂O₃-ZnO NCs was a spontaneous process and thermodynamically favorable. Finally, the proposed method was validated by applying it to real environmental water samples with reasonable results.     

Investigating the Effect of Ag and Au Nanostructures with Spherical and Rod Shapes on the Emission Wavelength of OLED

Noble metals, especially Ag and Au nanostructures, have unique and adjustable optical attributes in terms of surface plasmon resonance. In this research, the effect of Ag and Au nanoparticles with spherical and rod shapes on the light extraction efficiency and the FWHM of OLED structures was investigated using the finite difference time domain (FDTD) method. The simulation results displayed that by changing the shape and size of Ag and Au nanostructures, the emission wavelength can be adjusted, and the FWHM can be reduced. The presence of Ag and Au nanoparticles in the OLEDs showed a blue and red shift of the emission wavelength, respectively. Also, the Ag and Au nanorods caused a significant reduction in the FWHM and a shift to the longer wavelengths in the structures. The structures containing Ag nanorods showed the narrowest FWHM and longer emission wavelength than the other structures.

     

Effects of grapevine bunch exposure to sunlight on berry surface temperature and Lobesia botrana (Lepidoptera: Tortricidae) egg laying,hatching and larval settlement

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Maltodextrins as Chiral Selectors in CE: Molecular Structure Effect of Basic Chiral Compounds on the Enantioseparation

Prediction of chiral separation for a compound using a chiral selector is an interesting and debatable work. For this purpose, in this study 23 chiral basic drugs with different chemical structures were selected as model solutes and the influence of their chemical structures on the enantioseparation in the presence of maltodextrin (MD) as chiral selector was investigated. For chiral separation, a 100‐mM phosphate buffer solution (pH 3.0) containing 10% (w/v) MD with dextrose equivalent (DE) of 4‐7 as chiral selector at the temperature of 25°C and voltage of 20 kV was used. Under this condition, baseline separation was achieved for nine chiral compounds and partial separation was obtained for another six chiral compounds while no enantioseparation was obtained for the remaining eight compounds. The results showed that the existence of at least two aromatic rings or cycloalkanes and an oxygen or nitrogen atom or –CN group directly bonded to the chiral center are necessary for baseline separation. With the obtained results in this study, chiral separation of a chiral compound can be estimated with MD‐modified capillary electrophoresis before analysis. This prediction will minimize the number of preliminary experiments required to resolve enantiomers and will save time and cost. Chirality 26:620–628, 2014. © 2014 Wiley Periodicals, Inc.     

Mapping DNA damage‐dependent genetic interactions in yeast via party mating and barcode fusion genetics

Condition‐dependent genetic interactions can reveal functional relationships between genes that are not evident under standard culture conditions. State‐of‐the‐art yeast genetic interaction mapping, which relies on robotic manipulation of arrays of double‐mutant strains, does not scale readily to multi‐condition studies. Here, we describe barcode fusion genetics to map genetic interactions (BFG‐GI), by which double‐mutant strains generated via en masse “party” mating can also be monitored en masse for growth to detect genetic interactions. By using site‐specific recombination to fuse two DNA barcodes, each representing a specific gene deletion, BFG‐GI enables multiplexed quantitative tracking of double mutants via next‐generation sequencing. We applied BFG‐GI to a matrix of DNA repair genes under nine different conditions, including methyl methanesulfonate (MMS), 4‐nitroquinoline 1‐oxide (4NQO), bleomycin, zeocin, and three other DNA‐damaging environments. BFG‐GI recapitulated known genetic interactions and yielded new condition‐dependent genetic interactions. We validated and further explored a subnetwork of condition‐dependent genetic interactions involving MAG1, SLX4, and genes encoding the Shu complex, and inferred that loss of the Shu complex leads to an increase in the activation of the checkpoint protein kinase Rad53.     

Circulating immune complexes and complement C3 and C4 levels in a selected group of patients with rhinitis in Lebanon

BACKGROUND: A number of reports indicate that circulating immune complexes (CIC) and activation of the complement system contribute to the pathogenesis of Type I allergy. The aim of this study was to investigate the status of CIC in 113 patients with rhinitis in Lebanon and determine complement components C3 and C4 serum levels in the CIC-positive patients. Serum specific IgE antibodies were previously detected and reported in 74 of the 113 patients. METHODS: CIC were detected by polyethylene glycol precipitation and serum C3 and C4 levels quantified by radial immunodiffusion. RESULTS: CIC was positive in 20 of the specific IgE-positive and 13 of the specific IgE-negative patients. C3 and C4 levels were within the normal range in all the 33 CIC-positive patients. CONCLUSIONS: The antibody class that constitutes the complexes does not seem to be IgG or IgM. Moreover, complement activation does not seem to be involved in the allergic reaction since both C3 and C4 levels were normal in all patients. The role of these complexes, if any, in the pathogenesis of rhinitis is yet to be determined.     

Natural parasitism of the diamondback moth,Plutella xylostella (L.) (Lep.: Plutellidae) by a larval parasitoid wasp,Diadegma anurum on different cauliflower cultivars

The diamondback moth (DBM), Plutella xylostella (L.) (Lepidoptera: Yponomeutidae), is the most serious pest of cauliflower fields in central Iran and its control is primarily based on pesticide sprays. Over the past years, a number of new pesticide compounds were introduced onto the market and some of them may cause adverse effects on natural populations of parasitoids associated with DBM. Excessive use of insecticides against the pest did not produce satisfactory results but has caused concerns about environmental pollution and increased pest resistance to chemicals. This research aims to study natural parasitism of pest on different cauliflower cultivars in the fields of south of Tehran. Dominant species of parasitoids include Diadegma anurum, Cotesia plutellae and Oomyzus sokolowskii. The highest parasitism rate was observed by D. anurum that was recorded on Buris cultivar (19.92?±?1.06) and White cloud cultivar (16.20?±?1.49) and the lowest parasitism rate was observed on Snow crown cultivar (3.42) and SG cultivar (5.00) during the season.     

Improved Activity of a Thermophilic Cellulase,Cel5A,from Thermotoga maritima on Ionic Liquid Pretreated Switchgrass

Ionic liquid pretreatment of biomass has been shown to greatly reduce the recalcitrance of lignocellulosic biomass, resulting in improved sugar yields after enzymatic saccharification. However, even under these improved saccharification conditions the cost of enzymes still represents a significant proportion of the total cost of producing sugars and ultimately fuels from lignocellulosic biomass. Much of the high cost of enzymes is due to the low catalytic efficiency and stability of lignocellulolytic enzymes, especially cellulases, under conditions that include high temperatures and the presence of residual pretreatment chemicals, such as acids, organic solvents, bases, or ionic liquids. Improving the efficiency of the saccharification process on ionic liquid pretreated biomass will facilitate reduced enzyme loading and cost. Thermophilic cellulases have been shown to be stable and active in ionic liquids but their activity is typically at lower levels. Cel5A_Tma, a thermophilic endoglucanase from Thermotoga maritima, is highly active on cellulosic substrates and is stable in ionic liquid environments. Here, our motivation was to engineer mutants of Cel5A_Tma with higher activity on 1-ethyl-3-methylimidazolium acetate ([C₂mim][OAc]) pretreated biomass. We developed a robotic platform to screen a random mutagenesis library of Cel5A_Tma. Twelve mutants with 25–42% improvement in specific activity on carboxymethyl cellulose and up to 30% improvement on ionic-liquid pretreated switchgrass were successfully isolated and characterized from a library of twenty thousand variants. Interestingly, most of the mutations in the improved variants are located distally to the active site on the protein surface and are not directly involved with substrate binding.