Peptides with Dual Antimicrobial-Anticancer Activity Derived from the N-terminal Region of H. pylori Ribosomal Protein L1 (RpL1)

International Journal of Peptide Research and Therapeutics - Whereas the traditional approaches of cancer therapy including radiotherapy, chemotherapy, and immunotherapy have failed to properly...     

Computational Design and Analysis of a Multi-epitope Against Influenza A virus

International Journal of Peptide Research and Therapeutics - Influenza A viruses are among the most studied viruses, however no effective prevention against influenza infection has been developed....     

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.

     

Dental stem cell banking: Techniques and protocols

Dental tissue-derived stem cells (DSCs) provide an easy, accessible, relatively noninvasive promising source of adult stem cells (ASCs), which brought encouraging prospective for their clinical applications. DSCs provide a perfect opportunity to apply for a patient's own ASC, which poses a low risk of immune rejection. However, problems associated with the long-term culture of stem cells, including loss of proliferation and differentiation capacities, senescence, genetic instability, and the possibility of microbial contamination, make cell banking necessary. With the rapid development of advanced cryopreservation technology, various international DSC banks have been established for both research and clinical applications around the world. However, few studies have been published that provide step-by-step guidance on DSCs isolation and banking methods. The purpose of this review is to present protocols and technical details for all steps of cryopreserved DSCs, from donor selection, isolation, cryopreservation, to characterization and quality control. Here, the emphasis is on presenting practical principles in accordance with the available valid guidelines.     

Botanical candidates from Saudi Arabian flora as potential therapeutics for Plasmodium infection

Malaria is a lethal parasitic disease affecting over two hundred million people worldwide and kills almost half a million people per year. Until now, there is no curative treatment for this disease that has a substantial morbidity. The available chemotherapeutic agents are unable to completely control the infection with the continuous appearance of drug resistance. Consequently, the search for new therapeutic agents with high safety profiles and low side effects is of paramount importance. Several natural products have been investigated and proven to have antimalarial effects either in vivo or in vitro. A large number of plants have been studied globally for their antimalarial activities. However, studies that have been conducted in this field in Saudi Arabia are not enough. This article presents global and local research on the need for novel natural antimalarial agents with a particular emphasis on studies involving plants from Saudi Arabian flora.     

The codon-optimization of cfaE gene and evaluating its high expression capacity and conserved immunogenicity in Escherichia coli

Enterotoxigenic Escherichia coli (ETEC) is the most common cause of children diarrhea in the world. Adhesion of ETEC to small intestine is an important virulence trait. One of the most prevalent colonization factors (CFs) in human is CFA/I fimbriae and CfaE which is the required binding factor for adhesion of ETEC to intestinal mucosa.We optimized cfaE gene codons according to codon bias of E. coli to achieve a high level of recombinant protein expression. The optimized gene was expressed in E. coli and rCFaE protein was used for mice immunization. Blocking activity of the obtained antibody was examined by microplate agglutination inhibition test. SDS-PAGE analysis indicated that the optimized sequence of cfaE produces a suitable amount of rCFaE in comparison with native gene sequence. This optimized rCFaE protein could induces strong humoral response in mice and the antibody obtained against rCFaE inhibited the adhesion of ETEC to human group A erythrocytes. It is concluded that codon optimization is a useful approach for obtaining large quantities of recombinant rCFaE protein. With regard to the results of hemagglutination inhibition test, codon optimization and increased production of recombinant protein expressed in E. coli did not affect the immunogenicity potential of CFaE.     

How the Nucleus and Mitochondria Communicate in Energy Production During Stress: Nuclear MtATP6, an Early-Stress Responsive Gene, Regulates the Mitochondrial F1F0-ATP Synthase Complex

A small number of stress-responsive genes, such as those of the mitochondrial F₁F₀-ATP synthase complex, are encoded by both the nucleus and mitochondria. The regulatory mechanism of these joint products is mysterious. The expression of 6-kDa subunit (MtATP6), a relatively uncharacterized nucleus-encoded subunit of F₀ part, was measured during salinity stress in salt-tolerant and salt-sensitive cultivated wheat genotypes, as well as in the wild wheat genotypes, Triticum and Aegilops using qRT-PCR. The MtATP6 expression was suddenly induced 3 h after NaCl treatment in all genotypes, indicating an early inducible stress-responsive behavior. Promoter analysis showed that the MtATP6 promoter includes cis-acting elements such as ABRE, MYC, MYB, GTLs, and W-boxes, suggesting a role for this gene in abscisic acid-mediated signaling, energy metabolism, and stress response. It seems that 6-kDa subunit, as an early response gene and nuclear regulatory factor, translocates to mitochondria and completes the F₁F₀-ATP synthase complex to enhance ATP production and maintain ion homeostasis under stress conditions. These communications between nucleus and mitochondria are required for inducing mitochondrial responses to stress pathways. Dual targeting of 6-kDa subunit may comprise as a mean of inter-organelle communication and save energy for the cell. Interestingly, MtATP6 showed higher and longer expression in the salt-tolerant wheat and the wild genotypes compared to the salt-sensitive genotype. Apparently, salt-sensitive genotypes have lower ATP production efficiency and weaker energy management than wild genotypes; a stress tolerance mechanism that has not been transferred to cultivated genotypes.     

Large-scale purification of recombinant hepatitis B surface antigen from Pichia pastoris with non-affinity chromatographic methods as a substitute to immunoaffinity chromatography

Abstract

The costly media, inconsistent ligand density, ligand leakage, and possible destabilization of recombinant hepatitis B surface antigen (rHBsAg) particles are main drawbacks of using immunoaffinity chromatography (IAF) in the large-scale downstream processing. In this study, we aimed to use an efficient large-scale purification system as an alternative purification method for immunoaffinity chromatography. For this purpose, we suggested integrating non-affinity chromatographic methods of hydrophobic interaction chromatography (HIC) and size-exclusion chromatography (SEC) for cost-effective purification of rHBsAg expressed in P. pastoris. The optimization of such process is not trivial and straightforward since diverse molecular characteristics of expressed rHBsAg in each type of host cell cause different interactions in non-affinity chromatography processes. The working buffer composition and chromatography parameters are the most influential factors in hydrophobic interaction chromatography. The best result for lab-scale HIC was achieved by using ammonium sulfate buffer in 10% of saturation concentration in pH 7.0 with Butyl-S Sepharose 6 Fast Flow medium and with subsequent Tween-100 and urea elution. In this process, the recovery, purity, and total yield were about 84%, 82%, and 69%, respectively. By scaling-up the HIC and integrating it with Sephacryl S-400?SEC, we obtained highly pure, i.e.,?>?90%, rHBsAg virus-like particles (VLP).     

Effect of lead stress on mineral content and growth of wheat (Triticum aestivum) and spinach (Spinacia oleracea) seedlings

Lead (Pb) is the most common heavy metal contaminant in the environment. Pb is not an essential element for plants, but they absorb it when it is present in their environment, especially in rural areas when the soil is polluted by automotive exhaust and in fields contaminated with fertilizers containing heavy metal impurities. To investigate lead effects on nutrient uptake and metabolism, two plant species, spinach (Spinacia oleracea) and wheat (Triticum aestivum), were grown under hydroponic conditions and stressed with lead nitrate, Pb(NO₃)₂, at three concentrations (1.5, 3, and 15 mM).Lead is accumulated in a dose-dependent manner in both plant species, which results in reduced growth and lower uptake of all mineral ions tested. Total amounts and concentrations of most mineral ions (Na, K, Ca, P, Mg, Fe, Cu and Zn) are reduced, although Mn concentrations are increased, as its uptake is reduced less relative to the whole plant’s growth. The deficiency of mineral nutrients correlates in a strong decrease in the contents of chlorophylls a and b and proline in both species, but these effects are less pronounced in spinach than in wheat. By contrast, the effects of lead on soluble proteins differ between species; they are reduced in wheat at all lead concentrations, whereas they are increased in spinach, where their value peaks at 3 mM Pb.The relative lead uptake by spinach and wheat, and the different susceptibility of these two species to lead treatment are discussed.     

When to estimate sex ratio in natural populations of insects? A study on sex ratio variations of gall midges within a generation

Precise estimation of arthropods' sex ratio is an important issue in a wide range of ecological studies and biological control programs. Although, in many cases changes in arthropods' sex ratio may be under the control of parents or some symbiotic microorganisms, biased sex ratios in some other species are caused by some extrinsic factors, neglect of which may lead to under/overestimation of true sex ratio. In this paper, we pursued those factors that cause false estimation of sex ratio in insects' species. We studied the predatory gall midge, Aphidoletes aphidimyza Rondani (Diptera: Cecidomyiidae), an important biological control agent of aphids, that shows protandry (i.e. early male emergence), differential lifespan of sexes, and differential distribution of sexes across habitat. Ten populations of A. aphidimyza were released separately in transparent cages and their sex ratio variations were recorded every 12 hours. The primary sex ratio in this species seems to be slightly male‐biased (52.41% males), however early emergence of males biases the sex ratio up to 72% males in a few hours after emergence. Shortly after the emergence of females, the sex ratio reaches its primary situation, but as a result of male‐biased mortality after mating, the proportion of females increases gradually to 97% by the fourth and fifth days after emergence. These results explicitly suggest that direct estimation of sex ratio in natural populations may be affected by some secondary factors such as differential mortality of sexes, protandry, and differential distribution of males and females over time and/or across habitat.