Particulate matter and bacteria characteristics of the Middle East Dust (MED) storms over Ahvaz,Iran

The Middle East Dust storms have greatly affected the south and west parts of Iran during the last decade. The main purpose of this study was to examine and compare culturable airborne bacteria concentration in particulate matter (PM) during normal, semi-dust, and dust event days in different places and seasons in Ahvaz from November 2011 to May 2012. Sampling was performed every 6 days and on dust event days at different sampling stations. The overall mean concentrations of PM₁₀, PM_2.5, and PM₁ for the entire study period were 598.92, 114.8, and 34.5 μg/m³, respectively. The PM concentrations during the dust event days were much higher than normal and semi-dust event days. The highest mean PM concentrations were observed in March 2011. The low PM_2.5/PM₁₀ ratios indicate that these PM are mostly originating from natural sources such as dust storms. The overall mean concentration of total bacteria during the study period was 620.6 CFU/m³. The greatest bacterial concentrations were observed during dust event days and at areas with high traffic and more human activities compared with normal days and greener areas. The percentage of gram-positive bacteria was significantly higher than that during the study period (89 vs 11 %). During this study, 26 genera of culturable bacteria were identified from all the sampling stations. The most dominant genera in all sampling stations were Streptomyces, Bacillus, Kocuria, Corynebacterium, and Paenibacillus. The results also showed that there were positive correlations between PM and bacterial concentrations during the study period (p < 0.05).     

Tyrosine phosphorylation of GluR2 is required for insulin-stimulated AMPA receptor endocytosis and LTD

The alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) subtype of glutamate receptors is subject to functionally distinct constitutive and regulated clathrin-dependent endocytosis, contributing to various forms of synaptic plasticity. In HEK293 cells transiently expressing GluR1 or GluR2 mutants containing domain deletions or point mutations in their intracellular carboxyl termini (CT), we found that deletion of the first 10 amino acids (834-843) selectively reduced the rate of constitutive AMPA receptor endocytosis, whereas truncation of the last 15 amino acids of the GluR2 CT, or point mutation of the tyrosine residues in this region, only eliminated the regulated (insulin-stimulated) endocytosis. Moreover, in hippocampal slices, both insulin treatment and low-frequency stimulation (LFS) specifically stimulated tyrosine phosphorylation of the GluR2 subunits of native AMPA receptors, and the enhanced phosphorylation appears necessary for both insulin- and LFS-induced long-term depression of AMPA receptor-mediated excitatory postsynaptic currents. Thus, our results demonstrate that constitutive and regulated AMPA receptor endocytosis requires different sequences within GluR CTs and tyrosine phosphorylation of GluR2 CT is required for the regulated AMPA receptor endocytosis and hence the expression of certain forms of synaptic plasticity.     

Determination of atorvastatin in human serum by reversed-phase high-performance liquid chromatography with UV detection

A rapid and sensitive high-performance liquid chromatographic method was validated and described for determination of atorvastatin in human serum. Following liquid-liquid extraction of the drug and an internal standard (sodium diclofenac), chromatographic separation was accomplished using C18 analytical column with a mobile phase consisting of sodium phosphate buffer (0.05 M, pH 4.0) and methanol (33:67, v/v). Atorvastatin and the internal standard were detected by ultraviolet absorbance at 247 nm. The average recoveries of the drug and internal standard were 95 and 80%, respectively. The lower limits of detection and quantification were 1 and 4 ng/ml, respectively, and the calibration curves were linear over a concentration range of 4-256 ng/ml of atorvastatin in human serum. The analysis performance was studied and the method was applied in a randomized cross-over bioequivalence study of two different atorvastatin preparations in 12 healthy volunteers.     

Supportive properties of basement membrane layer of human amniotic membrane enable development of tissue engineering applications

Human amniotic membrane (HAM) has been widely used as a natural scaffold in tissue engineering due to many of its unique biological properties such as providing growth factors, cytokines and tissue inhibitors of metalloproteinases. This study aimed at finding the most suitable and supportive layer of HAM as a delivery system for autologous or allogeneic cell transplantation. Three different layers of HAM were examined including basement membrane, epithelial and stromal layers. In order to prepare the basement membrane, de-epithelialization was performed using 0.5 M NaOH and its efficiency was investigated by histological stainings, DNA quantification, biomechanical testing and electron microscopy. Adipose-derived stromal cells (ASCs) and a human immortalized keratinocyte cell line (HaCaT) were seeded on the three different layers of HAM and cultured for 3 weeks. The potential of the three different layers of HAM to support the attachment and viability of cells were then monitored by histology, electron microscopy and (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Moreover, mechanical strengths of the basement membrane were assessed before and after cell culture. The results indicated that the integrity of extra cellular matrix (ECM) components was preserved after de-epithelialization and resulted in producing an intact basement amniotic membrane (BAM). Moreover, all three layers of HAM could support the attachment and proliferation of cells with no visible cytotoxic effects. However, the growth and viability of both cell types on the BAM were significantly higher than the other two layers. We conclude that growth stimulating effectors of BAM and its increased mechanical strength after culturing of ASCs, besides lack of immunogenicity make it an ideal model for delivering allogeneic cells and tissue engineering applications.     

Nectary morphology in South West Asian Fritillaria (Liliaceae)

Nectaries of 3 1 taxa belonging to 4 subgenera of the genus Fritillaria are investigated by scanning electron and light microscopy. In most of the material investigated nectary cells were smaller and narrower, and less irregular in shape than those of the neighbouring tissue of the tepals. Species belonging to subgenus Rhinopetalum clearly differ from all other species. Their nectaries are deeply impressed, and the slit-like nectary orifice is bordered by two lobes, at least in the lower part densely hairy. In F. gibbosa, E karelinii and F. ariana, the flowers are ± zygomorphic as the nectary on the upper tepal is more deeply depressed than the others, and the nectary lobes are rather broad and fringed. In E stenanthera and E bucharica, nectaries are equally impressed in all tepals and the nectary orifice is bordered by narrow, unfringed ridges. The unique structure of nectaries in all species of this subgenus supports its separation from Fritillaria into a separate genus (Rhinopetalum Fisch. ex Alexand.). In the other subgenera, the nectaries are less impressed, often ± flattish, and usually linear to lanceolate or ovate, except in subgenus Petzlium where they are ± circular. One complex in subgenus Fritillaria is markedly distinguished from the rest of the subgenus: in the F. crassifolia group, the nectaries consist of a long and linear raised ridge with a median furrow. F. crassifolia ssp. poluninii is raised to specific level, E poluninii (fix) Bakhshi Khaniki & K. Persson, stat. nov. It is concluded that data on nectary morphology support the latest classification of the genus Fritillaria into subgenera and informal groups.     

Introduction of Beauveria bassiana as a biological control agent against the Ommatissus lybicus in Kerman province

Dubas bug, Ommatissus lybicus is one of the major sucking pests of date palm. Data palm is the most important economic crop in Iran. In this research, we isolated the pathogenic strain KB 201, KB 206, KB 211, KB 215, KB 220 and KB 512, of entomopathogenic fungi Beauveria bassiana from soil and insects, which produced aerial and submerged conidia and blastospores in the laboratory conditions. We investigated the best conditions for the production and utilisation of the spore suspension to spray the nymph of O. lybicus, which is one of the important pests in Kerman province (Iran). A total of 180 isolates that naturally infected by O. lybicus were collected from date palm in Kerman province during spring and summer seasons 2010–2011. The pathogen city test was carried out with direct spray. To bioassay the isolates, three concentrations of the spore suspension were prepared as follows: 1?×?10⁶, 1?×?10⁷ and 1?×?10⁸?conidia/ml. The pests were sprayed by aerial conidial suspension, which was prepared by 0.01% Tween 80 in distilled water, and the controls were sprayed by 0.01% Tween 80in distilled water. After spraying the pests, the plates were incubated at 25?±?1?°C and 80% of relative humidity. Then, the treated pests were monitored every day for the fungal growth and mortality.     

Soils selenium level and esophageal cancer: An ecological study in a high risk area for esophageal cancer

ProjectGolestan province, located in northeast of Iran, has been known as a high risk area for esophageal cancer (EC). This study was conducted to assess the relationship between soils selenium (Se) level and development of EC in this region.ProceduresIn this ecological study, 135 blocks were identified in Golestan province based on geographical altitude and longitude on the map. One soil sample was collected from the center of each block. Then we investigated Se concentration in soil samples by flame atomic absorption spectrometry. Statistical analysis was performed by the Pearson correlation test and Student t-tests. P-values of less than 0.05 were considered as significant.ResultsThe mean±SD of soils Se level in Golestan province was 3.7±1.61 mg/kg. There was a positive correlation between soils Se level and EC rates in this area (P=0.03) (Pearson correlation coefficient=0.19). Soils Se concentration was significantly higher in high (4.13 mg/kg) than in the low (3.39 mg/kg) EC rate areas (P=0.01).ConclusionsWe found high soils Se concentration and a significant positive relationship between soils Se level and EC rate in Golestan province of Iran. So, high soils Se level may play a possible role in developing EC in this area, specifically in Turkmensahra (very high EC rates).     

Safely removing cell debris with LC3‐associated phagocytosis

Phagocytosis and autophagy are two distinct pathways that degrade external and internal unwanted particles. Both pathways lead to lysosomal degradation inside the cell, and over the last decade, the line between them has blurred; autophagy proteins were discovered on phagosomes engulfing foreign bacteria, leading to the proposal of LC3‐associated phagocytosis (LAP). Many proteins involved in macroautophagy are used for phagosome degradation, although Atg8/LC3 family proteins only decorate the outer membrane of LC3‐associated phagosomes, in contrast to both autophagosome membranes. A few proteins distinguish LAP from autophagy, such as components of the autophagy pre‐initiation complex. However, most LAP cargo is wrapped in multiple layers of membranes, making them similar in structure to autophagosomes. Recent evidence suggests that LC3 is important for the degradation of internal membranes, explaining why LC3 would be a vital part of both macroautophagy and LAP. In addition to removing invading pathogens, multicellular organisms also use LAP to degrade cell debris, including cell corpses and photoreceptor outer segments. The post‐mitotic midbody remnant is another cell fragment, which results from each cell division, that was recently added to the growing list of LAP cargoes. Thus, LAP plays an important role during the normal physiology and homoeostasis of animals.