Radiation-Induced Oxidative Damage on Collagen Molecule and Protective Effects of N-Acetylcysteine in Guinea Pigs Liver

WOS: 000282930700025The main biological effects of radiation are mediated by short-lived and very reactive chemical molecules called free radicals. Free radicals can oxidatively damage biological macromolecules such as DNA, lipids and proteins. Antioxidants are enzymes or other organic substances, which prevent or reduce damage caused by free radicals. N-acetyl-L-cysteine (NAC), a thiol compound, shows its effects as an antioxidant by scavenging free radicals directly or by being the precurser of glutathione, which is an important protective agent against free radicals in vivo. The aim of this study was to investigate the potential radioprotective properties of NAC against irradiation-induced oxidative damages in the liver tissues of guinea pigs after total body irradiation with a single dose of 485 cGy. After 24 h following radiation exposure, an increase was observed in the levels both of liver thiobarbuturic acid reactive substance (TBARS), which is an indicator of lipid peroxidation, and hydroxyproline (HYP), which is a major component of collagen and an indicator of tissue fibrosis. Concurrently, administration of NAC (200 mg/kg IP) in the irradiated group for 5 consecutive days before radiation exposure apparently diminished activities of lipid peroxidation and ameliorated accumulation of hydroxyproline in liver. In conclusion, the data obtained from this study indicate that application of NAC increased the functions of endogeneous antioxidant defense mechanisms in guinea pigs, and hence protected the organisms from radiation-induced liver damages.Gazi University research foundationGazi UniversityThis work was supported by grants from the Gazi University research foundation

Lymph node ratio assessment of brain metastasis in early breast cancer cases

Background: Ten to 30% of early breast cancer (EBC) patients develop brain metastasis (BM) during their follow-up. In this study, we aimed to evaluate importance of the lymph node ratio (LNR) in development of BM in EBC cases. Materials and Methods: Ninety patients whom had axillary metastases in lymph nodes at their initial diagnosis and developed BM during 5-year follow-up were detected in 950 EBC patients. LNR values were calculated for all patients and after categorization into 4 molecular sub-types as luminal A, luminal B HER-2 (+), HER-2 overexpressing and basal- like. Comparison was with control group patients who had similar characteristics. Results: In the comparison of all molecular sub-types of LNR, 54.9% and 28.4% values were found in patients with and without BM respectively (p<0.001). In the comparison of the LNR with control groups, a statistically significant differences were found with luminal A with BM (p=0.001), luminal B HER-2 (p=0.001), HER-2 overexpressing (p=0.027) and basal-like groups (p<0.001). In the evaluation of patients with BM, the highest ratio was found in the basal-like group (67.9%) and there was a statistically significant difference between this group and the others (p=0.048). Conclusions: EBC patients developing BM within 5 years followup had significantly higher LNRs for all molecular sub-types, especially in the basal-like group. Larger scale studies are now needed for evaluating LNR prognostic importance for EBC regarding BM development

Meme kanserli 640 hastada hormon reseptör durumu ve C-erbB-2 düzeyi ile tedavi sonuçlari arasi iliski

Objective: In this study the relevant factors that effects the treatment outcomes of patients like hormone receptor and c-erbB-2 was established. Methods: The overall and disease-free survival rates were evaluated in 640 breast cancer patients. The mean follow-up was 59,1 months. Overall and disease-free survival rates found by Kaplan-Meier method at SPSS version 16.0. Log-Rank test evaluated the prognostic factors impact. Results: In ER (+) and (-) patients 5 year overall survival rates was 85,7%, 71,2% (p<0,001), disease free survival rates was 79,9%, 63,7% (p<0,001) respectively; in PR (+) and (-) patients 5 year overall survival rates was 85,6%, 71,6% (p<0,001), disease free survival rates was 79,6%, 64,3% (p<0,001) respectively. ER and PR positivity were significantly increased overall and disease-free survival. In c-erbB-2 over-expression 5 year overall survival rates was 76,4%, 85,3% (p=0,002), disease free survival rates was 69,7%, 79,1% (p=0,012) according to (-) patients. The worst prognosis had shown in ER (-), PR (-), cerbB- 2 (+) patients. Conclusion: ER, PR and c-erbB-2 levels have great importance in breast cancer and must be well considered in patients follow-up. © Copyright 2013 by Gazi University Medical Faculty

Results of chordoma patients treated by different approaches in a single institution

AIM: To discuss the optimal and recent treatment options based on clinical review of 16 chordoma patients. MATERIAL and METHODS: Data of the patients diagnosed and treated between 1999 and 2017 in Gazi University School of Medicine has been collected through patients' files and the electronic database of hospital records. Statistical analysis was applied to evaluate the correlation between the progression free survival and treatment modalities. RESULTS: Nine of the 16 patients were women (56.3\%). Half of the patients had intracranially located tumors, whereas the other 50\% of the sample had spinal (n=5) and sacral (n=3) chordomas. The median follow-up time was 51.7 months. Recurrence was observed in 50\% of patients, while the median recurrence time equaled to 27.6 months. Multivariate analysis results showed that age, gender tumor size, intra or extracranial location of tumor, treatment modalities, subtotal or grosstotal resection of tumor, radiotherapy dose, and techniques were not associated with recurrence. On the other hand, 2 patients are still under chemoterapy (imatinib, bevacizumab) without evident of recurrent disease. CONCLUSION: Despite the fact that surgery remains to be the cornerstone of treatment, total resection is not reasonable for all patients with chordomas. For this reason, adjuvant treatment for ensuring local control is highly important. If the residual tumor is of a small volume, SBRT may provide more advantages. Targeted treatment or chemotheapeutic agents may also be benificial for maintanence therapy. As the clinical awareness about chordomas is based on our series, aggressive multi-modality treatment options should be applied in the adjuvant therapy