Effects of ionizing radiation on the viability and proliferative behavior of the human glioblastoma T98G cell line

Abstract Objective Radiotherapy is the traditional therapy for glioma patients. Glioma has poor response to ionizing radiation (IR). Studying radiation-induced cell death can help in understanding the cellular mechanisms underlying its radioresistance. T98G cell line was irradiated with Co60 source by 2 or 10 Gy. MTT assay was used to calculate the surviving fraction. Cell viability, cell cycle distribution and apoptosis assays were conducted by flow cytometry for irradiated and control cells for the 10 Gy dose. Results The SF2 value for irradiated cells was 0.8. Cell viability was decreased from 93.29 to 73.61%, while, the Sub G0/G1 phase fraction was significantly increased at 10 Gy after 48 h. On the other hand, there was an increase in the percentage of apoptotic cells which reached 40.16% after 72 h at the same dose, while, it did not exceeds 2% for non-irradiated cells. Our results showed that, the T98G cells is radioresistant to IR up to 10 Gy. Effects of irradiation on the viability of T98G cells were relatively mild, since entering apoptosis was delayed for about 3 days after irradiation

High-resolution genotyping of Mycobacterium tuberculosis isolates from syria using mycobacterial interspersed repetitive unit-variable-number tandem repeat

Background: We aimed to evaluate the utility of 24 loci mycobacterial interspersed repetitive unit-variable-number tandem repeat (MIRU-VNTR) genotyping method for discrimination of clinical Mycobacterium tuberculosis isolates in Syria. Methods: We studied 68 clinical tuberculosis (TB) isolates originating from unrelated Syrian TB patients from different regions in Syria. Genetic types (consisting of 24 digits) were determined and used to construct a dendrogram. Results: Fifty-six distinct MIRU patterns were revealed, from which 52 patterns were represented by unique isolates. Sixteen isolates were distributed into 4 clusters, 3 of which consisted of isolates belonging to the TUR lineage. Nine MIRUs showed high Hunter-Gaston index (HGI) values (>0.6), with QUB-26 having the highest discriminatory power (HGI = 0.821), followed by MIRU10, MIRU26, MIRU16, and Mtub39. The cumulative HGI value of the 24-MIRU set was 0.985. Interestingly, using the reduced 15-MIRU, set resulted in the same HGI. The TUR lineage was the most frequent in our sample (23.5%), and it appears that it is widespread in Syria as in Turkey. The discriminatory power of MIRU-VNTR among the subset belonging to the TUR lineage was extremely low due to the high clustering rate (62.5%) of TUR isolates, indicating that this method is inappropriate to discriminate isolates of this lineage. On the other hand, the Beijing lineage was not represented in our isolates. Conclusion: We demonstrated the high prevalence of the TUR lineage and the low prevalence of the Beijing lineage among Syrian clinical TB isolates. The MIRU-VNTR method was highly discriminative among non-TUR TB isolates, but it was inappropriate to discriminate isolates of the TUR lineage