Exosomes for angiogenesis induction in ischemic disorders

Ischaemic disorders are leading causes of morbidity and mortality worldwide. While the current therapeutic approaches have improved life expectancy and quality of life, they are unable to “cure” ischemic diseases and instate regeneration of damaged tissues. Exosomes are a class of extracellular vesicles with an average size of 100–150 nm, secreted by many cell types and considered a potent factor of cells for paracrine effects. Since exosomes contain multiple bioactive components such as growth factors, molecular intermediates of different intracellular pathways, microRNAs and nucleic acids, they are considered as cell-free therapeutics. Besides, exosomes do not rise cell therapy concerns such as teratoma formation, alloreactivity and thrombotic events. In addition, exosomes are stored and utilized more convenient. Interestingly, exosomes could be an ideal complementary therapeutic tool for ischemic disorders. In this review, we discussed therapeutic functions of exosomes in ischemic disorders including angiogenesis induction through various mechanisms with specific attention to vascular endothelial growth factor pathway. Furthermore, different delivery routes of exosomes and different modification strategies including cell preconditioning, gene modification and bioconjugation, were highlighted. Finally, pre-clinical and clinical investigations in which exosomes were used were discussed.     

Heat stress aggravates oxidative stress,apoptosis, and endoplasmic reticulum stress in the cerebellum of male C57 mice

Molecular Biology Reports - The current study was set to assess the effect of heat stress exposure on oxidative stress, apoptosis, and endoplasmic reticulum stress markers in the cerebellum of male...     

A Comparative Study of a Novel Anti-reflective Layer to Improve the Performance of a Thin-Film GaAs Solar Cell by Embedding Plasmonic Nanoparticles

In this research work, a systematic design of a novel anti-reflective layer using embedded plasmonic nanoparticles is investigated for a thin-film GaAs solar cell. First, an anti-reflective layer that is made from ITO or SiO₂ is assumed in which Al nanoparticles are embedded inside them to manipulate the absorption and hence the photocurrent of a 500-nm GaAs solar cell. It is investigated that the Al nanoparticles embedded inside the anti-reflective coating improve the photocurrent of a GaAs solar cell. For instance, the 15.37 mA photocurrent is obtained for 500-nm bare GaAs cell, and it reached to 17.25 mA/cm² and 20.18 mA/cm² when an ITO anti-reflection is used with Al nanoparticles on top and inside that, respectively. It increases to 21.94 mA/cm² and 24.98 mA/cm² in the case of the anti-reflective layer made from SiO₂ and Al nanoparticles at the top side or inside that, respectively. Finally, using a double anti-reflective layer that is made from SiO₂-TiO₂, the maximum photocurrents of 23.79 mA/cm² and 24.68 mA /cm² are obtained when Al nanoparticles are at the top side or inside that, respectively. The simulation results show that the embedding Al nanoparticles in the anti-reflective layer can improve the photocurrent of a thin-film GaAs solar cell.

     

Application of Bacillus pumilus as a potential biocontrol agent of Fusarium wilt of tomato

The current study aimed at evaluating the possibility of native Bacillus pumilus species to control Fusarium wilt in tomato and examine its effect on plant growth. Biocontrol traits of B. pumilus strains, biofilm assay, root colonisation and in vivo studies under pot conditions were determined. Strain ToIrMA-KC806242 formed biofilm efficiently and could colonise and survive on tomato rhizosphere (3.1 × 10⁴ CFU/g of root). The amount of auxin production was recorded 29.7 μg/ml at the 96th hour of incubation. Siderophore production was determined positive, while ToIrMA was not able to solubilise phosphate compounds or produce cyanide hydrogen. Statistical analysis of data revealed that the increase in root and shoot length was recorded 60 and 84%, respectively, over control. In addition, about 73% reduction in disease incidence was determined in vivo experiments. In conclusion, this study suggests B. pumilus ToIrMA strain as a possible biocontrol agent in the field experiments.     

Reaction of sunflower varieties to Sclerotinia sclerotiorum under various inoculation methods,time of field evaluation and phylogenic stages of host

Sunflower cultivation is affected seriously by Sclerotinia sclerotiorum (Lib.) de Bary in Iran, particularly north-western areas. Because of economic and environmental harms by chemical control, it is necessary to develop cultivars with adequate genetic resistance for reduction of yield losses. The purpose of this study was to find an effective method of inoculation with S. sclerotiorum under field evaluations. Three stem-inoculation techniques including: 1 – mycelium plug, 2 – oxalic acid solution (OAS) and 3 – infested wheat seeds with Sclerotinia mycelium were employed under field conditions. Four genotypes including Ghalami (local variety in market), Confeta, Allstar and Master were used in this study. The lesion length, lesion width and lesion as up and down leading on the stem from inoculation site were measured after 3, 7, 10 and 14 days of inoculation. The analysis of variance showed significant difference between all employed techniques and incubation days after inoculation. Mycelial plug (MP) inoculation technique produced significantly more developed lesions on the treated stems. In spite of this effect, Master variety demonstrated reasonable resistance reaction against the disease. The progress of disease in wounded treatments was also faster than the non-wounded ones. And, the shortest time to obtain significant differences between varieties was 10?days after inoculation. By comparison of results of lesion length at flowering and seed-filling stages, the more obvious effectiveness of the disease was observed at the second stage. Finally, there were negative correlations between mean temperature and mean lesion length in all three inoculation methods.     

Using phylogeographic approaches to analyse the dispersal history,velocity and direction of viral lineages — Application to rabies virus spread in Iran

Recent years have seen the extensive use of phylogeographic approaches to unveil the dispersal history of virus epidemics. Spatially explicit reconstructions of viral spread represent valuable sources of lineage movement data that can be exploited to investigate the impact of underlying environmental layers on the dispersal of pathogens. Here, we performed phylogeographic inference and applied different post hoc approaches to analyse a new and comprehensive data set of viral genomes to elucidate the dispersal history and dynamics of rabies virus (RABV) in Iran, which have remained largely unknown. We first analysed the association between environmental factors and variations in dispersal velocity among lineages. Second, we present, test and apply a new approach to study the link between environmental conditions and the dispersal direction of lineages. The statistical performance (power of detection, false‐positive rate) of this new method was assessed using simulations. We performed phylogeographic analyses of RABV genomes, allowing us to describe the large diversity of RABV in Iran and to confirm the cocirculation of several clades in the country. Overall, we estimate a relatively high lineage dispersal velocity, similar to previous estimates for dog rabies virus spread in northern Africa. Finally, we highlight a tendency for RABV lineages to spread in accessible areas associated with high human population density. Our analytical workflow illustrates how phylogeographic approaches can be used to investigate the impact of environmental factors on several aspects of viral dispersal dynamics.     

Use of Coupled Al-Ag Bimetallic Cylindrical Nanoparticles to Improve the Photocurrent of a Thin-Film Silicon Solar Cell

In this paper, cylindrical shape coupled bimetallic plasmonic nanoparticles (NPs) were used to improve the performance of a thin-film silicon solar cell. Our design is based on the appropriate selection of the composition and morphology of the NPs to reach a cell with excellent optical properties. The specific interaction between the incident light and bimetallic NPs helps us to design better solar absorbers. Here, the FDTD method was used to evaluate the effect of cylindrical Al-Ag bimetallic NPs on the surface of a thin silicon absorber. At first, a unit cell with Al-Al paired nano-cylinders at the surface was evaluated and a photocurrent of 14.65 mA/cm² was obtained. In the case of a cell with paired Al-Ag bimetallic nano-cylinders, the photocurrent was increased to 16.15 mA/cm². This value was increased to 16.57 mA/cm² when paired polymetallic NPs were used. According to the results of this work, bimetallic and polymetallic nanoparticles can significantly improve the photocurrent of an ultra-thin silicon solar cell. The results of this work can be used to design better plasmonic-based light trapping systems for thin-film solar cells.

     

Entropic Forces Drive Cellular Contact Guidance

Contact guidance—the widely known phenomenon of cell alignment induced by anisotropic environmental features—is an essential step in the organization of adherent cells, but the mechanisms by which cells achieve this orientational ordering remain unclear. Here, we seeded myofibroblasts on substrates micropatterned with stripes of fibronectin and observed that contact guidance emerges at stripe widths much greater than the cell size. To understand the origins of this surprising observation, we combined morphometric analysis of cells and their subcellular components with a, to our knowledge, novel statistical framework for modeling nonthermal fluctuations of living cells. This modeling framework is shown to predict not only the trends but also the statistical variability of a wide range of biological observables, including cell (and nucleus) shapes, sizes, and orientations, as well as stress-fiber arrangements within the cells with remarkable fidelity with a single set of cell parameters. By comparing observations and theory, we identified two regimes of contact guidance: 1) guidance on stripe widths smaller than the cell size (w ≤ 160 μm), which is accompanied by biochemical changes within the cells, including increasing stress-fiber polarization and cell elongation; and 2) entropic guidance on larger stripe widths, which is governed by fluctuations in the cell morphology. Overall, our findings suggest an entropy-mediated mechanism for contact guidance associated with the tendency of cells to maximize their morphological entropy through shape fluctuations.     

Curcumin ameliorated myocardial infarction by inhibition of cardiotoxicity in the rat model

Cardiovascular diseases are the main cause of death globally. Many attempts have been done to ameliorate the pathological changes after the occurrence of myocardial infarction. Curcumin is touted as a polyphenol phytocompound with appropriate cardioprotective properties. In this study, the therapeutic effect of curcumin was investigated on acute myocardial infarction in the model of rats. Rats were classified into four groups; control, isoproterenol hydrochloride (ISO) (100 mg/kbw), curcumin (50 mg/kbw), and curcumin plus ISO treatment groups. After 9-day administration of curcumin, levels of lactate dehydrogenase (LDH), creatine kinase (CK), and cardiac troponin I (cTnI) were determined. Superoxide dismutase (SOD) and malondialdehyde (MDA) contents were measured to investigate the oxidative status in infarct rats received curcumin. By using H & E staining, tissue inflammation was performed. Masson’s trichrome staining was conducted to show cardiac remodeling and collagen deposition. The number of apoptotic cells was determined by using the terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Data showed the serum decrease of LDH, CK, and cTnI in infarct rats after curcumin intake compared to the rats given (ISO) ( P < 0.05). Curcumin was found to reduce oxidative status by reducing SOD and MDA contents ( P < 0.05). Gross and microscopic examinations revealed that the decrease of infarct area, inflammation response and collagen deposition in rats given ISO plus curcumin ( P < 0.05). We noted the superior effect of curcumin to reduce the number of apoptotic cardiomyocytes after 9 days. Data point the cardioprotective effect of curcumin to diminish the complication of infarction by the reduction of cell necrosis and apoptosis in a rat model of experimental infarction.