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Biomedical subjects

O Akyol

Publications and source records attributed to O Akyol.

33 records · Page 2Linked to original sources

Superoxide dismutase, catalase, glutathione peroxidase and xanthine oxidase in diabetic rat lenses.

The activities of the protective enzymes, superoxide dismutase, catalase, glutathione peroxidase and of xanthine oxidase, an enzyme acting as a source of O(-)(2), were measured in the lenses of alloxan-induced diabetic and control rats. Superoxide dismutase and glutathione peroxidase activities were found to be significantly decreased, while catalase and xanthine oxidase activities were increased. This means that the ratio of the oxidant/antioxidant enzymes increases in the diabetic rat lens, suggesting an increased oxidative stress. This imbalance is possibly an important contributing factor in the pathogenesis of diabetic cataract.

Animals↗

The risk of coronary heart disease in men with androgenetic alopecia.

BACKGROUND: The meaningful association of androgenetic alopecia and coronary heart disease has been well documented, but few studies have focused on the importance of lipid parameters, such as total cholesterol, triglycerides, high density lipoprotein-cholesterol, low density lipoprotein-cholesterol, lipoprotein (a), apolipoprotein A1 and apolipoprotein B in patients with androgenetic alopecia. OBJECTIVE: The aim of this study is to investigate the relation between androgenetic alopecia and coronary heart disease and to determine the significance of certain lipid parameters on this relationship. SUBJECTS: Forty-one men with vertex type androgenetic alopecia (study group) and 36 men, age-matched, with normal hair status (control group) were the subjects of this study. RESULTS: We found significant differences in serum lipoprotein (a) and triglyceride levels between the study and control groups (P < 0.05). Forty-seven percent of patients and 30% of controls had a lipoprotein (a) level more than 30 mg/dl higher than the level critical for atherosclerotic heart disease. CONCLUSION: Dermatologists should investigate lipid profile, especially lipoprotein (a), of patients with androgenetic alopecia and refer to a cardiologist if necessary.

Adult↗

Serum immunoglobulin E (Ig E) levels after myocardial infarction.

The relation between cardiovascular diseases and serum immunoglobulin E (Ig E) levels has been investigated by different authors. Serum Ig E may play a direct role in the pathogenesis of cardiovascular diseases, or it may only be a marker formed during pathological mechanisms. In this study, we determined serum Ig E levels of patients with unstable angina pectoris and myocardial infarction. Serum Ig E levels of 30 patients with acute myocardial infarction and 20 patients with unstable angina pectoris were determined within the first 6 and 12th hours and on 2nd, 4th, 8th days of the hospitalization and these levels were compared with the serum Ig E levels of normal subjects reserved as control group. As a result, at all measurement hours, serum Ig E levels of acute myocardial infarction group were found to be approximately fourfold increased when compared to those of unstable angina pectoris and those of control group (p < 0.001). In the acute myocardial infarction group, no significant differences could be found between the levels of the first 6th and 12th hours and on the 2nd, 4th, 8th days. Also, no statistically significant difference was found between the serum Ig E levels of unstable angina pectoris and those of control group.

Adult↗

Concentrations of some major and minor elements in larynx tissues with and without cancer.

In this study, concentrations of some major and minor elements were determined in the larynx tissues with and without cancer, and results obtained were statistically compared. No meaningful differences were found between sodium, potassium, calcium and copper concentrations in cancer tissues, corresponding cancer-free adjacent tissues and in control larynx tissues. Phosphate concentrations of the cancer tissues were higher compared with cancer-free adjacent tissues and control tissues. Iron, zinc and magnesium concentrations were found increased in both cancer and corresponding cancer-free adjacent tissues relative to control values. Intra- and inter-element correlations established within and between groups indicated that relations between elements were also disordered in the cancer tissues. We suggest that the changed element status of cancerous larynx tissues may arise from increased requirements of cancer tissues for some elements such as iron, zinc, magnesium and phosphate.

Adult↗

Adenosine deaminase, 5'-nucleotidase, xanthine oxidase, superoxide dismutase, and catalase activities in gastric juices from patients with gastric cancer, ulcer, and atrophic gastritis.

Adenosine deaminase (ADA), 5'-Nucleotidase (5NT), Xanthine oxidase (XO), Cu-Zn Superoxide dismutase (SOD) and Catalase (CAT) activities were determined in gastric juices from patients with gastric cancer, ulcer, gastritis and from healthy subjects. Enzyme activities were given as units per ml gastric juice and units per mg protein in gastric juice. ADA, 5NT and XO activities were found lower and protein concentrations were found higher in the cancer group than controls. There was however no significant difference between Cu-Zn SOD activities of the cancer and control groups. In all groups including control one, we could not find catalase activities in most of the samples. On the other hand, ADA, 5NT activities and protein concentrations in the gastric juice were lower in the gastritis group than control group. In the ulcer group, we found higher Cu-Zn SOD and XO activities and lower 5NT activity and protein concentrations compared with control values. In an attempt to establish statistical correlations between mean enzyme activities, pH and protein concentrations in the gastric juices of the groups, we found noticeable intra and inter-correlations, which indicated possible relations between DNA and free radical metabolizing enzymes.

5'-Nucleotidase↗

Adenosine deaminase, 5'nucleotidase, xanthine oxidase, superoxide dismutase, and catalase activities in cancerous and noncancerous human bladder tissues.

Activities of adenosine deaminase (ADA), 5'nucleotidase (5NT), xanthine oxidase (XO), superoxide dismutase (SOD), and catalase (CAT) enzymes were measured in cancerous and cancer-free adjacent bladder tissues from 36 patients with bladder cancer and in control bladder tissues from 9 noncancer patients. Increased ADA and decreased XO, SOD, and CAT activities were found in cancerous bladder tissues compared with those of cancer-free adjacent tissues and of control bladder tissues. Differences were also found between enzyme activities in the bladder of different disease stages and grades. In the cancerous tissues, only positive intracorrelations were found, but in the cancer-free adjacent tissues and control tissues, both positive and negative correlations were established between enzyme activities. Results suggested that purine metabolism and salvage pathway activity of purine nucleotides were accelerated in the cancerous human bladder tissues via increased ADA and decreased XO activities, probably together with changes in some other related enzyme activities and, free radical metabolising-enzyme activities were depressed in cancerous bladder tissues, which indicated exposure of cancerous tissues to more radicalic stress.

5'-Nucleotidase↗

Serum adenosine deaminase and total superoxide dismutase activities before and after surgical removal of cancerous laryngeal tissue.

In this study, pre- and post-operative serum activities of adenosine deaminase (ADA) and total superoxide dismutase (SOD) enzymes were measured in patients with squamous cell laryngeal cancer. Activities of both enzymes were found to be higher in cancerous patients compared to the controls. No significant differences were found however between pre- and post-operative values for both enzymes in the patient group. It has been suggested that ADA and SOD enzymes leak from the cancerous laryngeal tissues into the blood stream. The absence of differences between pre- and post-operative serum enzyme activities has two possible explanations: Firstly, removal of previously released enzymes from the blood stream takes a much longer period than one month; and secondly, cancerous laryngeal tissue is not the only source of the enzymes mentioned even after removal of cancerous tissue by surgical operation, other sources such as adjacent tissues and/or metastatic tissues etc, still release these enzymes into the blood stream.

Adenosine Deaminase↗

Reduced erythrocyte defense mechanisms against free radical toxicity in patients with chronic renal failure.

In this study, activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) enzymes were determined in the erythrocytes from patients with chronic renal failure (CRF) and from healthy subjects. In the conservative drug management group and intermittent ambulatory peritoneal dialysis group, CAT activity was lower than in the control group. However, SOD and GSH-Px activities of these groups were not statistically different from the control values. In the continuous ambulatory peritoneal dialysis group and the hemodialysis group, SOD, GSH-Px and CAT activities were lower than control values. In the patient groups, correlation coefficients between the enzyme activities were also found to be different from the control values. Results suggested that enzymatic antioxidant defense mechanisms were suppressed in the erythrocytes from the patients with CRF, in particular in the erythrocytes from those who were under hemodialysis and continuous ambulatory peritoneal dialysis management. It is proposed that reduced antioxidant defense mechanisms in the erythrocytes is one of the important factors leading to peroxidation in the membrane lipid structure of the erythrocytes and thereby to hemolysis and anemia in the patients with CRF.

Adolescent↗

Plasma chromium levels in hypoglycemic preterm, full-term and in intrauterine-growth-retarded babies.

Serum chromium levels of hypoglycemic preterm and full-term babies were investigated. Normoglycemic preterm and full-term babies were selected as the control group. There was no statistically significant difference in serum Cr levels between preterm and full-term, hypoglycemic and normoglycemic, preterm hypoglycemic and preterm normoglycemic, full-term hypoglycemic and full-term normoglycemic babies. Serum Cr levels of intrauterine-growth-retarded babies were relatively low compared to infants appropriate for gestational age. Serum Cr levels of babies with mothers younger than 35 years of age had significantly lower levels than older mothers' babies.

Chromium↗

Adenosine deaminase, 5' nucleotidase, xanthine oxidase, superoxide dismutase, and catalase activities in cancerous and noncancerous human laryngeal tissues.

We determined activities of adenosine deaminase (ADA), 5' nucleotidase (5NT), xanthine oxidase (XO), superoxide dismutase (Cu-Zn SOD), and catalase (CAT) enzymes in 15 human laryngeal tissues with well-differentiated squamous cell carcinomas, in 15 corresponding tumor-free adjacent tissues and in 7 normal laryngeal tissues. We found lower ADA and 5NT and higher XO, Cu-Zn SOD, and CAT activities in cancerous tissues than those in corresponding noncancerous ones. In the correlation analysis, we established one positive intercorrelation, which was between ADA activities of tumor tissues and noncancerous adjacent tissues. We also found some significant intracorrelations between enzyme activities of the tissues, all of which were positive in cancerous ones.

5'-Nucleotidase↗

Glutathione peroxidase activity in serum during acute myocardial infarction and unstable angina pectoris.

We studied GSH-Px enzyme activity in serum after acute myocardial infarction (AMI) and unstable angina pectoris (UAP). The study included 15 patients with AMI and 9 patients with UAP. Serum GSH-Px activity in the AMI group (0.992 +/- 0.071) (IU/ml) was higher than that of the UAP group. Serum GSH-Px activity was established as 0.683 +/- 0.110 (IU/ml) in UAP and 1.012 +/- 0.121 (IU/ml) in 10 healthy subjects (p < 0.0005). We suggest that measurement of serum GSH-Px activity together with other enzyme tests such as CK-MB, LDH, GOT, etc. can be helpful in the differentiation of AMI from UAP.

Angina, Unstable↗