جستجوی مقالات مرتبط با کلیدواژه "free radical" در نشریات گروه "پزشکی"

 Oral squamous cell carcinoma (OSCC) is the most common malignancy of the oral cavity, which is usually caused by the most common premalignant lesion of oral leukoplakia (OL). For changes of dysplasia and malignancy, the level of antioxidants in the blood and tissue of patients changes significantly, which may be effective in early diagnosis of malignancies. Therefore, the purpose of this study is to evaluate antioxidants (enzymatic and non-enzymatic) in the blood of patients with OSCC and OL.

This study is a case-control study and was conducted on 75 blood samples of patients with OSCC and OL referred to the Cancer Institute of Imam Khomeini Hospital, Ilam. Enzymatic antioxidants [catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx)] and non-enzymatic antioxidants (ascorbic acid, beta-carotene, vitamin E) were evaluated in the blood of patients. The data obtained from this study were evaluated by ANOVA test and the significance level (P<0.5) was considered.

The results showed that the mean age in the HC group was similar in both sexes, while in the OL group, the age of women was 4 years younger, and in the OSCC group, the age of women was 2 years older than men. CAT, as an antioxidant indicator, significantly increased in the OL group compared to the HC group and OSCC group (P < 0.000). Also, CAT and SOD activity in OSCC serum samples significantly decreased compared to the HC group (P < 0.000). GPx also showed a significant decrease in both OL and OSCC groups compared to the HC group (P < 0.000). The results related to the non-enzymatic antioxidant factors, beta-carotene, vitamin E, and ascorbic acid, significantly decreased in both OL and OSCC groups compared to the HC group (beta-carotene (P < 0.000), vitamin E (P < 0.000), and ascorbic acid (P < 0.000)).

The results of this study show that the level of enzymatic antioxidants and beta-carotene in is not related to the degree of dysplasia of oral leukoplakia, therefore, it is not possible to predict the probability of occurrence of malignant oral lesions based on the measurement of the level of antioxidants in patients with OL.

Intense sports activity, by creating oxidative stress, plays a role in causing some muscle damage and the spread of inflammation after the activity. On the other hand, it has been stated that oxidative stress tolerance can be done by stress proteins such as hemoxygenase. Therefore, the aim of the present study was to determine and investigate the effect of intense endurance training on hemoxygenase-1 and TNF-α enzyme levels in the stomach and intestinal tissues of male Wistar rats.

In the present experimental study conducted in 2017, 16 male Wistar rats aged 8 weeks were randomly divided into 2 groups (control and intense endurance training) after 10 familiarization sessions and weight lifting (mean and the standard deviation of the control group was 203.125 ± 8.18 and intense endurance training was 211.25 ± 7.9). The intense endurance training protocol included running on a treadmill for 8 weeks (5 sessions per week), water and standard food were freely provided to the samples. 48 hours after the last training session and 4-hour fasting, the mice were dissected and tissue samples were collected, and hemoxygenase-1 enzyme concentration and TNF-α level were measured using an ELISA kit. Collected data were analyzed using independent t-test.

The results indicated that intense endurance training had no significant effect on the level of hemoxygenase enzyme in the stomach tissue of rats (p=0.88). Moreover, the amount of hemoxygenase-1 enzyme in the intestinal tissue of mice did not change significantly (p=0.79). The amount of TNF-α in the stomach tissue of mice was not meaningfully different between the two groups (p=0.48). The amount of TNF-α in the intestinal tissue of the two groups was not significantly different (p=0.12).

Due to the non-change of TNF-α level, probably regular endurance sports training made the stomach and intestinal tissues safe from the destructive effects of intense endurance training by creating a beneficial adaptation in the antioxidant system. On the other hand, there is a possibility that the lack of significant changes in the inflammatory index in the present study could be related to the intensity of the exercise used. Correspondingly, if the intensity of sports activity is suitable for changes in inflammatory index levels, the lack of proper exercise by the samples of the present study was probably a factor in the absence of significant changes.

There are many reports published about the use of cold atmospheric plasma in cancer treatment recently. In this way, the selective effects of cold plasma on the breast (MDA-MB-231) and cervical (Hela) cancer cells were studied as a new cancer treatment method.

In this study, cold atmospheric pressure plasma was generated using a plasma jet reactor and also optical emission spectroscopy (OES) was used to investigate the free radicals produced by the plasma. Futhermore, the effects of helium and helium-oxygen gas mixtures and the time of plasma radiation on the viability of MDA-MB-231 and Hela cells immediately, 24 and 48 hours after radiation were determined by MTT assay. In this account, in order to investigate the selective effects of plasma, direct treatment method was used to evaluate the viability of normal fibroblast cell line.

The results of optical emission spectroscopy showed that decreasing the sample distance from the plasma jet nozzle and increasing operating voltage increased the free radicals produced by plasma. Increasing the time of direct plasma radiation from one to five minutes reduced the vitality of the cancer cells. The most anti-cancer response was observed 48 hours after plasma irradiation and in the helium-oxygen gas mixture. Also, the results showed that cancer cells are more sensitive than normal fibroblast cells to plasma treatment.

According to the promising results of this study, reducing the viability of cancer cells and fewer toxic effect on normal cells, cold plasma therapy can be considered as a new method for cancer therapy.