No abstract

Tonsillitis which is commonly referred to a strep throat is caused by group A β-hemolytic streptococci (GABHS) or Streptococcus pyogenes. The bacteria is consider as one of the major human-specific bacterial pathogen and one of its virulence factors is the streptokinase; for this reason, 100 tonsillitis swabs were taken from Iraqi children suffering from symptoms of sore throat. Using conventional cultural methods, 60 bacterial isolates were characterized and subjected to biochemical tests. As a result, 40 isolates were identified as hemolytic bacteria and only 6 of them were identified as Streptococcus. pyogens using Bacitracin (0.04) and Vitek 2 system. The ability of the 6 isolates for streptokinase production was screened and the results showed that all of them were produce the enzyme with variable degrees. Molecular detection of streptokinase gene using real time PCR technique has been done with specific primers and the amplification results were present with all S.pyogens strains.

Drug development is a time-consuming and expensive process, given the low success rate of clinical trials. Now, anticancer drug developments have shifted to three-dimensional (3D) models which are more likely to mimic tumor behavior compared to traditional two-dimensional (2D) cultures. A comparative study among different aspects was conducted between 2D and 3D cultures using colorectal cancer (CRC) cell lines, in addition, Formalin-Fixed Paraffin-Embedded (FFPE) block samples of patients with CRC were used for evaluation. Compared to the 2D culture, cells grown in 3D displayed significant (p < 0.01) differences in the pattern of cell proliferation over time, cell death phase profile, expression of tumorgenicity related genes and responsiveness to 5-fluorouracil, cisplatin, and doxorubicin, compared with 2D cultured cells. Epigenetically, 3D cultures and FFPE shared the same methylation pattern and microRNA expression, while 2D cells showed elevation in methylation rate and altered microRNA expression. Lastly, transcriptomic study depending on RNA sequencing and thorough bioinformatic analyses showed significant (p-adj < 0.05) dissimilarity in gene expression profile between 2D and 3D cultures involving thousands of genes (up/down-regulated) of multiple pathways for each cell line. Taken together, the study provides insights into variation in cellular morphologies between cells cultured in 2D and 3D models.