Improved cellular response on functionalized polypyrrole interfaces

Neuroregeneration strategies involve multiple factors to stimulate nerve regeneration. Neural support with chemical and physical cues to optimize neural growth and replacing the lesion neuron and axons are crucial for designing neural scaffolds, which is a promising treatment approach. In this study, polypyrrole polymerization and its functionalization at the interface developed by glycine and gelatin for further optimization of cellular response. Nanofibrous scaffolds were fabricated by electrospinning of polyvinyl alcohol and chitosan solutions. The electrospun scaffolds were polymerized on the surface by pyrrole monomers to form an electroactive interface for further applications in neural tissue engineering. The polymerized polypyrrole showed a positive zeta potential value of 57.5 ± 5.46 mV. The in vitro and in vivo biocompatibility of the glycine and gelatin-functionalized polypyrrole-coated scaffolds were evaluated. No inflammatory cells were observed for the implanted scaffolds. Further, DAPI nucleus staining showed a superior cell attachment on the gelatin-functionalized polypyrrole-coated scaffolds. The topography and tuned positively charged polypyrrole interface with gelatin functionalization is expected to be particularly efficient physical and chemical simultaneous factors for promoting neural cell adhesion.     

Investigation of apoptosis in cultured cells infected with equine herpesvirus 1

Many viruses alter different stages of apoptosis of infected cells as a strategy for successful infection. Few studies have addressed mechanisms of equine herpesvirus 1 (EHV-1) strain-induced cell death. We investigated the effect of an abortigenic strain (AR8 strain) on heterologous Madin–Darby bovine kidney cells and homologous equine dermis (ED) cells cell lines. We compared morphologic and biochemical features of early and late apoptosis at different postinfection times. We investigated translocation of phosphatidylserine to the cell surface, nuclear fragmentation and changes in the cytoskeleton using flow cytometry and annexin V/propidium iodide staining, DNA laddering, terminal deoxynucleotidyl transferase UTP nick-end labeling assay and immunofluorescence staining of cytokeratin 18 cleavage. AR8 EVH-1 strain interfered with apoptosis in both cell lines, particularly during the middle stage of the replication cycle; this was more evident in ED cells. Although this antiapoptotic effect has been reported for other alpha herpesviruses, our findings may help elucidate how EHV-1 improves its infectivity during its cycle.     

Liposomes: an overview of manufacturing techniques

During the last few decades liposomes have attracted great interest as ideal models for biological membranes as well as efficient carriers for drugs, diagnostics, vaccines, nutrients and other bioactive agents. The extensive and ever increasing literature covering the field of liposomology written by researchers with diverse backgrounds is an indication of increasing interest in this field. Many techniques and methodologies have evolved for the manufacture of liposomes, on small and large scales, since their introduction to the scientific community around 40 years ago. This article intends to provide an overview of the advantages and disadvantages of liposome preparation methods in general with particular emphasis on the heating method, developed in our laboratory, as a model technique for fast production of the lipid vesicles.     

First report of occurrence of two viruses on pea field in Iran

An intensive survey was conducted to identify virus diseases affecting pea crops in Tehran province of Iran. A total of 270 pea samples were collected randomly from pea fields. samples were tested by Double Antibody Sandwich Enzyme Linked Immunosorbent Assay (DAS-ELISA) using polyclonal antisera prepared against PSBMV (AS-0129, DSMZ, Braunschweig, Germany) and TSWV (AS-0580, DSMZ, Braunschweig, Germany). Virus disease incidence in pea samples was followed by PSBMV (33%) TSWV (24.4%) and PSBMV+TSWV (17.77). The positive samples with PSBMV were extracted in 0.05M phosphate buffer pH 6.5-7 containing 2% pvp and inoculated on Pisum sativum, Vicia faba, Chenopodium quinoa, Chenopodium amaranticolor. That produced in Pisum sativum; leaflets roll downwards, shoots curl, internodes shorten and plants are rosetted. Early infections reduce flower and fruit formation or eliminate their development. Broad bean has symptoms accompanied by a certain margin rolling and leaflet distortion. In Chenopodium amaranticolor necrotic local lesions and Chenopodium quinoa chlorotic local lesions had produced. The positive samples with TSWV were extracted in 0.01 M phosphate buffer containing 1% Na2 SO3 and inoculated on Petunia hybrida, Pisum sativum. TSWV causes several symptoms in infected peas, including brown leaf petiole and stem coloration, leaflet spotting, vein necrosis. In petunia hybrida after approximately 5 days showed local necrotic lesion. Biological purification in TSWV with chlorotic local lesions in Petunia hybrida and in PSBMV; chlorotic local lesions in Chenopodium quinoa were done. In PSBMV, back inoculated on Pisum sativum and Vicia faba also tested with DAS-ELISA. RT-PCR confirmed the results. This is the first report of PSBMV and TSWV naturally infecting pea in Iran.     

Functional Gene Hybridization Patterns of Terrestrial Ammonia-Oxidizing Bacteria

Abstract The biochemical pathway and genetics of autotrophic ammonia oxidation have been studied almost exclusively in Nitrosomonas europaea. Terrestrial autotrophic ammonia-oxidizing bacteria (AAOs), however, comprise two distinct phylogenetic groups in the beta-Proteobacteria, the Nitrosomonas and Nitrosospira groups. Hybridization patterns were used to assess the potential of functional probes in non-PCR-based molecular analysis of natural AAO populations and their activity. The objective of this study was to obtain an overview of functional gene homologies by hybridizing probes derived from N. europaea gene sequences ranging in size from 0.45 to 4.5 kb, and labeled with 32P to Southern blots containing genomic DNA from four Nitrosospira representatives. Probes were specific for genes encoding ammonia monooxygenase (amoA and amoB), hydroxylamine oxidoreductase (hao), and cytochrome c-554 (hcy). These probes produced hybridization signals, at low stringency (30 degreesC), with DNA from each of the four representatives; signals at higher stringency (42 degreesC) were greatly reduced or absent. The hybridization signals at low stringency ranged from 20 to 76% of the total signal obtained with N. europaea DNA. These results indicate that all four functional genes in the ammonia oxidation pathway have diverged between the Nitrosomonas and Nitrosospira groups. The hao probe produced the most consistent hybridization intensities among the Nitrosospira representatives, suggesting that hao sequences would provide the best probes for non-PCR-based molecular analysis of terrestrial AAOs. Since N. europaea can also denitrify, an additional objective was to hybridize genomic DNA from AAOs with probes for Pseudomonas genes involved in denitrification. These probes were specific for genes encoding heme-type dissimilatory nitrite reductase (dNir), Cu-type dNir, and nitrous oxide reductase (nosz). No hybridization signals were observed from probes for the heme-type dNir or nosz, but Nitrosospira sp. NpAV and Nitrosolobus sp. 24-C hybridized, under low-stringency conditions, with the Cu-type dNir probe. These results indicate that AAOs may also differ in their mechanisms and capacities for denitrification.     

Construction of stable anionic liposome-plasmid particles using the heating method: a preliminary investigation

Recent advances in liposome technology have resulted in the production of effective drug delivery formulations, although toxicity concerns remain. In order to overcome this problem we prepared anionic liposomes without using any volatile organic solvent or detergent. Liposomes prepared by this heating method (HM-liposomes) were characterised in terms of morphology, stability and DNA incorporation efficiency. Scanning tunnelling microscopy (STM) and optical microscopy were used to study the morphological characteristics and size distribution of HM-liposomes. Microscopic studies revealed formation of spherical bilayered structures with stabilities of at least eight months and also enabled measuring the diameter and the bilayer thickness of the vesicles. Plasmid DNA encapsulation efficiencies of up to 70.3% were determined for HM-liposomes.     

Study of interaction effect between triacontanol and nitric oxide on alleviating of oxidative stress arsenic toxicity in coriander seedlings

In this study, triacontanol (TRIA) and nitric oxide (NO) interaction on arsenic (As)-induced oxidative stress tolerance in coriander (Coriandrum sativum L.) plants was investigated. The results showed that As had a significant adverse effect on the plant’s biomass. The seedlings pretreated with TRIA and NO significantly increased growth reduction induced by the metalloid. The obtained results indicated that the application of TRIA and sodium nitroprusside (SNP) generally reduced oxidative markers such as of electrolyte leakage percentage, malondialdehyde and H₂O₂ contents under As toxicity, while application of As treatment without TRIA?+?SNP increased these oxidative parameters compared to the control. The non-enzymatic antioxidant contents such as total phenol, anthocyanin, carotenoid, ascorbic acid and reduced glutathione (GSH) were extracted and assayed from both control and treated plants. It was found that TRIA?+?SNP treatments have a profound effect on the antioxidant metabolism and caused an enhancement in non-enzymatic antioxidant potentials under As toxicity in coriander. Moreover, the results revealed a mutually amplifying reaction between TRIA and NO in reducing As-induced damages.     

Oxidative Stress Parameters,Trace Elements,and Lipid Profile in Iranian Patients with Gaucher Disease

Biological Trace Element Research - Gaucher disease (GD) is most frequent disorder of glycolipid storage. The glucosylceramide accumulation might lead to oxidative stress and changes in lipid...     

Effects of different amino acids on somatic embryogenesis of strawberry (<Emphasis Type="Italic">Fragaria</Emphasis> × <Emphasis Type="Italic">ananassa</Emphasis> Duch.)

This study was conducted to optimize different types and concentrations of amino acids on somatic embryogenesis induction, development and maturation of leaf explants in strawberry cultivars (‘Camarosa’, ‘Paros’ and ‘Kurdistan’). Calli derived from leaf sections were transferred onto MS medium with 1.0 mg/l 2,4-d + 0.5 mg/l BAP supplemented with 0.0, 50, 100, 150 or 200 mg/l concentrations of proline, alanine and glutamine. Stimulation of embryogenesis and embryo development was strictly dependent on the type and concentration of amino acid in the medium. Proline (100 mg/l) was much more effective than glutamine and alanine, on induction and development of somatic embryogenesis in all cultivars. Cultures grown on amino acid-free medium attained lower somatic embryos than cultures grown on amino acid treated medium. Low concentrations (50 mg/l) and high concentrations (200 mg/l) of amino acids tested were inefficient for embryogenesis induction as well as for somatic embryos development.