All the world is involved in the COVID-19 disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Coronavirus is a positive-sense RNA and has an envelope. There is no specific drug for this disease and treatment methods are limited. Malnutrition and electrolyte imbalance can make dysfunction in the immune system and impairment of the immune system causes increasing the risk of infection. Understanding the aspects of biological features of the virus will help the development of diagnostic tests, pharmacological therapies, and vaccines. Here, we review and discuss increasing and decreasing some trace elements and imbalance of serum and plasma electrolytes involving in COVID-19.

Mobile phones and Wi-Fi radiofrequency radiation are among the main sources of the exposure of the general population to radiofrequency electromagnetic fields (RF-EMF). Previous studies have shown that exposure of microorganisms to RF-EMFs can be associated with a wide spectrum of changes ranged from the modified bacterial growth to the alterations of the pattern of antibiotic resistance. Our laboratory at the nonionizing department of the Ionizing and Non-ionizing Radiation Protection Research Center has performed experiments on the health effects of exposure to animal models and humans to different sources of electromagnetic fields such as cellular phones, mobile base stations, mobile phone jammers, laptop computers, radars, dentistry cavitrons, magnetic resonance imaging, and Helmholtz coils. On the other hand, we have previously studied different aspects of the challenging issue of the ionizing or nonionizing radiation-induced alterations in the susceptibility of microorganisms to antibiotics. In this study, we assessed if the exposure to 900 MHz GSM mobile phone radiation and 2.4 GHz radiofrequency radiation emitted from common Wi-Fi routers alters the susceptibility of microorganisms to different antibiotics. The pure cultures of Listeria monocytogenes and Escherichia coli were exposed to RF-EMFs generated either by a GSM 900 MHz mobile phone simulator and a common 2.4 GHz Wi-Fi router. It is also shown that exposure to RF-EMFs within a narrow level of irradiation (an exposure window) makes microorganisms resistant to antibiotics. This adaptive phenomenon and its potential threats to human health should be further investigated in future experiments. Altogether, the findings of this study showed that exposure to Wi-Fi and RF simulator radiation can significantly alter the inhibition zone diameters and growth rate for L monocytogenes and E coli. These findings may have implications for the management of serious infectious diseases.

Recently, special attention has been paid to marine origin compounds such as carbohydrates, peptides, lipids, and carotenoids, which are extracted from microalgae and have anticancer, anti-inflammatory, antimicrobial (e.g., anti-COVID-19 activity), and antioxidant properties in biomedicine and pharmaceutical biotechnology. In addition, these photosynthetic marine microorganisms have several applications in biotechnology and are suitable hosts for the production of recombinant proteins/peptides, such as monoclonal antibodies and vaccines. Silica-based nanoparticles obtained from diatoms (a microalgae group) are used as drug delivery carriers owing to their biodegradability, easy functionalization, low cost, and simple features compared to synthetics, which make these agents proper alternatives for synthetic silica nanoparticles. Therefore, diatom-based nanoparticles are a viable option for the delivery of anti-cancer drugs and reducing the side-effects of cancer chemotherapy.

Various strategies have been utilized to improve both gene transfer efficiency and cell-induced toxicity of polyethylenimine (PEI), the most extensively investigated cationic polymeric vector. In this study, we sought to enhance transfection efficiency of low molecular weight PEI (LMW PEI) while maintaining its low toxicity by cross-linking LMW PEI via succinic acid linker. These modifications were designed to improve the hydrophilic–hydrophobic balance of the polymer, by enhancing the buffering capacity and maintaining low cytotoxic effects of the final conjugate. Decreased expression of CD200 in the central nervous system has been considered as one of the proposed mechanisms associated with neuroinflammation in multiple sclerosis; therefore, we selected plasmid-encoding CD200 gene for transfection using the modified PEI derivatives. Dynamic light scattering experiments demonstrated that the modified PEIs were able to condense plasmid DNA and form polyplexes with a size of approximately 130 nm. The highest level of CD200 expression was achieved at a carrier to plasmid ratio of 8, where the expression level was increased by 1.5 fold in the SH-SY5Y cell line, an in vitro model of neurodegenerative disorders. Furthermore, the results of in vivo imaging of the LMW PEI-based nanoparticles in the mouse model of multiple sclerosis revealed that fluorescently labeled plasmid encoding CD200 was distributed from the injection site to various tissues and organs including lymph nodes, liver, brain, and finally, kidneys. The nanoparticles also showed the ability to cross the blood–brain barrier and enter the periventricular area.

Introduction: The prevalence of nosocomial infections in patients hospitalized to three hospitals of Shahid Beheshti, Farshchian, and Be' saat in Hamadan was investigated for 2 years (2018 to 2020). Materials and Methods: The samples were cultured and characterized using morphological and diagnostic biochemical tests. The analysis of the frequency of the isolates and their antibiotic resistance were calculated using SPSS (version 22) at a significant level of P-value < 0.05. Results: Bacterial isolates were collected from the 1194 clinical specimens, of which 1394 were isolated from urine, 16 from CSF, and 588 from tracheal aspiration. Also, 654 (54.8%) isolates were obtained from females and 540 (45.2%) from males with the age range 15-73 years (P> 0.05). The results showed that 22.1% were gram-positive and 77.9% were gramnegative. In our study, the frequency of Klebsiella pneumoniae bacteria was higher than in some studies, and this indicates the genetic changes and resistance of this bacterium to many antibiotics. Conclusion: To prevent further spread of resistance, increase the effectiveness of antibiotics and prevent multidrug resistance, it is essential to establish a precise schedule for the use of antibiotics and assess the resistance pattern periodically in each region based on the antibiotic resistance pattern.

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Purpose: To investigate the protective effect of preconditioning with non-toxic dose of hydrogenperoxide (H2O2) as a possible cell signaling molecule, against cell death induced by toxicconcentration of H2O2 or by serum deprivation in human Wharton’s jelly-derived mesenchymalstem cells (HWJ-MSCs) and underlying mechanisms.Methods: HWJ-MSCs were isolated and identified using flow cytometry. After finding non-toxicconcentration of H2O2, cells preconditioning was performed by H2O2 (20 μM) for 12 h and celltolerance against serum deprivation or toxic levels of H2O2 was assayed by MTT test. Effect ofpreconditioning on mRNA and protein expression of Akt-1, Bcl-2 and Bax were examined usingreverse transcription polymerase chain reaction (RT-PCR) and western blotting respectively. Roleof hypoxia-inducible factor (HIF)-1α was explored in presence HIF-1α inhibitor.Results: Preconditioning with 20 μM H2O2 for 12 h was non-toxic and decreased cell deathinduced by oxidative stress and serum deprivation in MSC cultures. However, the increasedtolerance reversed in the presence of inhibitor of HIF-1α. By regards to RT-PCR and westernblotting data, although expression of Akt-1, Bcl-2 and Bax was not change considerably butphosphorylated Akt-1 (pAkt-1) was up regulated after treatment with 20 μM H2O2 compared tocontrol group. Moreover after exposure to 100 μM H2O2, western blotting analysis showed thatcell pretreatment with 20 μM H2O2, decremented Bax/Bcl2 ratio and up-regulated HIF-1α andpAkt-1 compared to the control group.Conclusion: Increased tolerance of H2O2-pretreated cells led to the suggestion that transplantationof H2O2 preconditioned MSCs may improve therapeutic potential of stem cells in cell therapyprocedures.

Background: The increasing use of telecommunication devices such as Wi-Fi modems and mobile phones in the recent years can change the cellular structure of microorganisms so the generation of electromagnetic waves has led to concern in the community whenever be exposed to these fields and may have harmful effects on human health.Material and Methods: Standard strains of bacteria were prepared on Mueller-Hinton agar for bacterial growth to obtain 0.5 McFarland turbidity (1.5 × 108 CFU) of bacteria. Antibiotic susceptibility testing using the Kirby-Bauer disk diffusion method was done. For Staphylococcus aureus and Pseudomonas aeruginosa, antibiotics susceptibility test was conducted. The test group was exposed to electromagnetic waves emitted by mobile phone simulator with a frequency of 900 MHz and the control group didin’t exposed.Results: The results revealed that increasing duration of exposure to electromagnetic waves emitted by the mobile simulators with a frequency of 900 MHz especially after 24 h of exposure, can increase bacterial resistance in S. aureus, and P. aeruginosa.Conclusion: Several factors can cause bacterial resistance against antibiotics. One of these factors is the electromagnetic waves emitted from mobile simulator with a frequency of 900 MHz, which can increase the permeability of the cell wall of bacteria.