Effect of Moderate Static Magnetic Fields on Mice Oocyte Vitrification: Calcium-Related Genes Expression.

The ability to cryopreserve oocytes without ultrastructural injury has been a concern in the development and use of methods to preserve female reproduction. The stability of the cell membrane must be preserved to reduce the damage caused by ice crystals during vitrification. One approach that has been explored is the use of static magnetic fields (SMFs), which are believed to influence cell membrane stability. In this study, the in vitro effects of SMF that range between 20-80 mT on the vitrification of mice germinal vesicle (GV) oocytes were studied. The viability and mitochondrial (Mt) membrane potential of both vitrified and nonvitrified oocytes were assessed using Trypan blue and JC1 staining. The high in vitro maturation (IVM) rate and high Mt membrane potential in metaphase II (MII) oocytes were taken into account to determine the optimal magnetic field intensity, that is, 20 mT. None of the SMF conditions resulted in intact spindles in MII oocytes. The study also explored the expression of store-operated calcium entry (Stim1, Orai1, and Ip3r) and meiosis resumption (Ccnb, Cdk) genes in GV and MII oocytes of both vitrified and control groups. The results show that the expressions of Orai1 and Ccnb genes in Vit-MII-SMF oocytes were considerably increased. However, no significant difference in Stim1 expression was observed between the groups. The Vit-MII-SMF group exhibited a significantly higher Ccnb expression compared to other groups. In vitro fertilization (IVF) was performed to evaluate the 2 pronuclear (2PN) rates. The findings demonstrated that using 20 mT SMF improved 2PN rates compared to the nonvitrified groups. This study provides a deeper understanding of the effects of moderate SMF and vitrification on the expression of calcium channel genes in GV and MII oocytes. The results suggest that applying a 20 mT SMF can help prevent cryoinjury and enhance the characteristics of vitrified-warmed oocytes.

Conjugated PNC-27 peptide/PEI-superparamagnetic iron oxide nanoparticles (SPIONs) as a double targeting agent for early cancer diagnosis: In vitro study.

Objectives: Superparamagnetic iron oxide nanoparticles (SPIONs) have been considered promising non-invasive imaging tools in medicine. However, their high surface energy leads to NPs aggregation, while non-targeted SPIONs can cause cytotoxic effects on normal cells. In this work, we evaluated the in vitro potential of polyethyleneimine (PEI)-SPIONs targeted by PNC-27 peptide as a double targeting agent throughout early cancer diagnosis. Materials and Methods: Initially, PEI was conjugated to PNC-27 with HDM-2-binding domain. Then, SPIONs were loaded into PEI-PNC-27 through the ligand exchange method. The physicochemical characteristics of the synthesized NPs were evaluated. The cytotoxicity and targeting efficiency were assayed against HT-29 and CT-26 cell lines along with NIH-3t3 as normal cells by MTT method and Prussian blue staining test, respectively. Results: The mean diameter of synthesized carriers was obtained in the range of 86.6 - 116.1 nm with a positive charge. According to the cytotoxicity results, the binding and uptake abilities of the PNC-27 peptide by cancer cells were significantly higher than that of the NIH-3t3 cells. However, the results were indicative of the more toxic impacts of targeted synthesized NPs against CT-26 cancer cell line when being compared with HT-29 cells, which may be caused by the different cytotoxicity mechanisms of NPs. In addition, the targeted carriers and SPIONs were present inside and around the cells with HDM-2 expression along with only a few non-targeted vectors, while displaying no appearance throughout the normal cell. Conclusion: The results indicated the efficiency of targeted PEI-coated SPIONs for cancer diagnostic applications.

Stem cell research and therapy in the Islamic republic of Iran: pioneering in the Islamic world.

In the early 2000s, the Iranian stem cell research and technology had a relatively strong start that benefited from religious blessings, political and public support, as well as scientific endeavors on the part of non-governmental and public research organizations and universities. Later on, it developed a dynamic niche market of public, private start-up, and spin-off companies and organizations that pioneered in the Islamic world in terms of ISI papers, clinical trials, and cell therapy. However, at present, it faces new challenges stemming from the insufficient finance and a comprehensive law and regulation structure to keep its momentum. To remedy this situation, the scientific community and other stakeholders need to have a series of shared long-time goals and try to build consensus on how to achieve them through nationally approved policy documents.

Probing the interaction of human serum albumin with bilirubin in the presence of aspirin by multi-spectroscopic, molecular modeling and zeta potential techniques: insight on binary and ternary systems.

Here, we report on the effect of aspirin (ASA), on the binding parameters with regard to bilirubin (BR) to human serum albumin (HSA). Two different classes of binding sites were detected. Binding to the first and second classes of the binding sites was dominated by hydrophobic forces in the case of HSA-BR, whereas in the case of the ternary system, binding to the first and second classes of the binding sites was achieved by electrostatic interaction. The binding constant (K(a)) and number of binding site (n) obtained were 1.6 × 10(6)M(-1) and 0.98, respectively, for the primary binding site in the case of HSA-BR, and 3.7 × 10(6)M(-1) and 0.84, respectively, in the presence of ASA (ternary complex) at λ(ex)= 280 nm. The progressive quenching of the protein fluorescence as the BR concentration increased indicated an arrangement of the domain IIA in HSA. Changes in the environment of the aromatic residues were also observed by synchronous fluorescence spectroscopy (SFS). Changes of the secondary structure of HSA involving a decrease of α-helical and ß-sheet contents and increased amounts of turns and unordered conformations were mainly found at high concentrations of BR. For the first time, the relationship between the structural parameters of HSA-BR by RLS for determining the critical induced aggregation concentration (C(CIAC)) of BR in the absence and presence of ASA was investigated, and there was a more significant enhancement in the case of the ternary mixture as opposed to the binary one. Changes in the zeta potential of HSA and the HSA-ASA complex in the presence of BR demonstrated a hydrophobic adsorption of this anionic ligand onto the surface of HSA in the binary system as well as both electrostatic and hydrophobic adsorption in the case of the ternary complex. By performing docking experiments, it was found that the acting forces between BR and HSA were mainly hydrophobic > hydrogen bonding > electrostatic interactions, and consequently BR had a long storage time in blood plasma, especially in the presence of ASA. This was due to the electrostatic interaction force between the BR and HSA being stronger in (HSA-ASA) BR than in the HSA-BR complex. In addition, it was demonstrated that, in the presence of ASA, the first binding site of BR on HSA was altered, but the parameters of binding did not become significantly modified, and thus the affinity of BR barely changed with and without ASA.