miRNA-based electrochemical biosensors for ovarian cancer.

Ovarian cancer, a prevalent and deadly cancer among women, presents a significant challenge for early detection due to its heterogeneous nature. MicroRNAs, short non-coding regulatory RNA fragments, play a role in various cellular processes. Aberrant expression of these microRNAs has been observed in the carcinogenesis-related processes of many cancer types. Numerous studies highlight the critical role of microRNAs in the initiation and progression of ovarian cancer. Given their clinical importance and predictive value, there has been considerable interest in developing simple, prompt, and sensitive miRNA biosensor strategies. Among these, electrochemical sensors have demonstrated advantageous characteristics such as simplicity, sensitivity, low cost, and scalability. These microRNA-based electrochemical biosensors are valuable tools for early detection and point-of-care applications. This article discusses the potential role of microRNAs in ovarian cancer and recent advances in the development of electrochemical biosensors for miRNA detection in ovarian cancer samples.

Bactericidal Activity of Serum by Brucella Abortus RB51 Outer Membrane Protein's Combined by Brucella Abortus S99 Lipopolysaccharide Induction.

Background: Brucellosis vaccines are designed to induce cellular immunity. An effective brucellosis vaccine could induce both cellular and humoral immunity. Serum Bactericidal Assay (SBA) is an important method for determining vaccine humoral immunity. This study is the first to observe humoral immunity in brucellosis by SBA. Methods: Extracted Brucella abortus (B. abortus) Lipopolysaccharide (LPS) and Outer Membrane Proteins (OMPs) were injected into rabbits. Group 1 was injected with 25 µg of LPS, Group 2 was injected with 50 µg of OMPs, and Group 3 was injected with 1 ml of combined vaccine, 3 times every 2 weeks. The groups were challenged with B. abortus 544 in the second injection. Sera were separated 2 weeks after the last injection. SBA was performed, and each well was streak-cultured into a plate of Brucella agar. A colony count was done for each plate. Results: Results have shown, the third injection of the combined vaccine had the highest titer of 1 64 , and the efficacy of the vaccine was 87.71%. Conclusion: As a conclusion, the results of this study showed that LPS and OMP's from B. abortus can provide acceptable immunity.

Production of egg yolk antibody (IgY) against a chimeric protein containing IpaD, StxB, and TolC antigens from Shigella: An investigation of its prophylactic effects against Shiga toxin (Stx) and Shigella dysenteriae in vitro and in vivo.

Shigella is a major problem in developing countries. Immunoglobulin Y (IgY) can be used for prophylaxis and neutralize bacteria. The aim of this study was to produce IgY against the chimeric protein containing IpaD, StxB, and TolC antigens from Shigella, investigate its prophylactic and neutralizing effects against Stx and Shigella dysenteriae. The nucleotide sequence corresponding to the chimeric protein was cloned into pET28a plasmid and expressed in E. coli BL21 (DE3). Protein expression was confirmed by SDS-PAGE and the recombinant protein was purified by Ni-NTA affinity chromatography. The 150 µg of chimeric protein was mixed with Freund's adjutant and injected into laying hens (Leghorn). IgY was purified using PEG6000 precipitation. Antibody titer in the serum and egg yolk was evaluated by ELISA. IgY challenge against 1,10 and 50 LD50 of Stx and S. dysenteriae was investigated. A 60.6 kDa recombinant protein was confirmed by SDS-PAGE. ELISA showed that the antibody titer was significantly increased. MTT assay [3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide] showed that at 16 µmol/L, IgY protected HeLa cells against Stx. Treatment of mice with 1000 and 1500 µg IgY leads to complete survival of the mice against 1LD50 toxin and 4000 µg of IgY led to complete survival against 1LD50, also 70% and 30% survival against 10 and 50 LD50S. dysenteriae. This study showed that IgY produced against Stx and Shigella virulence factors could cause high protective effects against bacteria and toxins.