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ABSTRACT Objective Thyroid hormones are known to affect the biosynthesis and degradation of antioxidant compounds, suggesting a possible link between hypothyroidism and oxidative stress. However, there is no clear consensus in the literature regarding this association. The aim of this study was to evaluate oxidative stress markers (extracellular thiol-disulfide homeostasis and intracellular glutathione homeostasis) in patients with hypothyroidism due to autoimmune (Hashimoto’s thyroiditis) or nonautoimmune thyroid disease rendered euthyroid after levothyroxine replacement. Subjects and methods The study included 116 patients admitted to the Taksim Training and Research Hospital (Istanbul, Türkiye). Of these, 50 had hypothyroidism due to Hashimoto’s thyroiditis (HT group), 30 had nonautoimmune hypothyroidism (NAIH group), and 36 were healthy controls (control group). All participants were women. Extracellular thiol-disulfide homeostasis and intracellular glutathione homeostasis tests were assessed as oxidative stress markers. Results Thiol-disulfide homeostasis in both HT and NAIH groups was shifted toward the oxidative spectrum. Compared with the control group, the HT and NAIH groups had lower levels of native (p < 0.001 and p = 0.001, respectively) and total (p = 0.002 and p = 0.012, respectively) thiol, as well as a lower native thiol/total thiol ratio (p < 0.001 for both). The HT group also had higher disulfide levels than the control group (p = 0.027). Reduced glutathione (GSH) and oxidized glutathione (GSSG) values were comparable across all three groups, but the HT and NAIH groups had higher GSSG/GSH (p < 0.001 for both) and GSSG/(GSH+GSSG) ratios (p = 0.003 and p = 0.005, respectively), along with lower GSH/(GSH+GSSG) ratio (p = 0.001 and p = 0.002, respectively) than the control group. Conclusion Levothyroxine replacement was ineffective in ameliorating oxidative stress in patients with hypothyroidism due to Hashimoto’s thyroiditis or nonautoimmune causes, as extracellular thiol-disulfide homeostasis was notably altered in these patients compared with healthy controls. The findings of this study suggest that oxidative stress remains a prevailing issue in patients with autoimmune or nonautoimmune hypothyroidism even after euthyroidism is restored.

(1) Reduced glutathione (GSH) is considered the first line of antioxidant defense. During oxidative stress, it is oxidized to glutathione disulphide (GSSG). (2) A simple and quick spectrophotometric method based on sodium borohydride (NaBH4) as a reductant to measure the total and reduced GSH in porcine saliva was analytically validated and evaluated in two situations in this species: (a) in a physiological situation, involving sows during the late lactation and post-weaning periods, and (b) in a situation of sepsis in pigs experimentally induced by LPS administration. (3) The results of the analytical validation showed that the assay was precise and accurate in the porcine saliva samples. Higher total GSH and GSSG and lower reduced GSH were observed in the saliva of sows during the post-weaning period, as well as in pigs with experimentally induced sepsis. (4) In conclusion, the validated assay showed adequate analytical results and could be used to evaluate the GSH system of porcine saliva, as demonstrated during the clinical performance.

IgA vasculitis (IgAV) is a leukocytoclastic vasculitis affecting small vessels and is more common in children than in adults. In this study, we aimed to investigate the effects of oxidative stress in adult IgAV patients by Dynamic Thiol Disulfide Homeostasis (DTDH) and Ischemia Modified Albumin (IMA) levels. We also aimed to correlate the presence of inflammation detected by C-Reactive Protein (CRP) and Highly Sensitive C-Reactive Protein (hsCRP) with these oxidative stress parameters. Forty-one IgAV patients and forty-five controls were included in the study. Patients were classified as "active" or "in remission" according to the British Vasculitis Activity Score (BVAS). Measured parameters were compared between the groups. DTDH, IMA, CRP and hsCRP parameters were analyzed in both patient and control groups. According to our results, disulfide (p=0.047), index 1 (p [Med-Science 2023; 12(3.000): 758-63]

Aim. We aimed to examine the thiol-disulfide (SS) balance, a recognized marker of oxidative stress, in fibromyalgia syndrome (FMS). Methods. The study comprised 98 female participants (61 newly diagnosed patients and 37 patients under treatment) with FMS, along with 82 apparently healthy female volunteers. In both groups, assessments were conducted using the Fibromyalgia Impact Questionnaire (FIQ), Visual Analogue Scale (VAS), Pittsburgh Sleep Quality Index (PSQI), Fatigue Severity Scale (FSS), Short Form-36 (SF-36), Tender Point Count, Beck Depression Inventory (BDI), and Beck Anxiety Inventory (BAI). Native thiol (NT) and total thiol (TT) levels were measured, SS levels and SS/NT ratio were calculated. Results. FMS patients demonstrated significantly lower NT levels, higher SS levels, and an elevated SS/NT ratio compared to the control group (p< 0.05 for all groups). In FMS patients, a statistically significant correlation was found between SS level and the SS/NT ratio, as well as the number of tender points (r=-0.24, p=0.02; r=-0.21, p=0.04), SF-36 pain subscales (r=0.22, p=0.032; r=0.21, p=0.04), and BAI scores (r=-0.22, p=0.01; r=-0.23 p=0.03). In the subgroup analysis, all health assessment scales were observed to exhibit statistically significant differences between the under-treatment group and newly-diagnosed group when compared to the control group (p< 0.05 for all groups). The FIQ, VAS, FSS, and BAI scores were found to be significantly lower in the under-treatment group as compared to the newly-diagnosed group (p< 0.05 for all groups). In the newly-diagnosed group, NT was significantly lower and the SS/NT ratio was significantly higher than those in the control group (p< 0.05). In the under-treatment group, SS levels and SS/NT ratio were significantly higher as compared to the control group (p< 0.05). In the multivariate regression analysis, which incorporated age, health assessment scales, patient subgroups, tender points, and duration of symptoms to predict the SS/NT ratio, variabes such as being in the under-treatment group, tender points, and BAI score were identified as significant predictors (p< 0.05). Conclusions. The thiol-SS balance was observed to shift in the oxidative direction, and oxidative stress was higher in the FMS group. The absence of a significant difference between the under-treatment group and the newly-diagnosed group in terms of thiol-SS balance parameters suggests a shift to oxidative stress in patients, independent of the treatment status.

Background: To investigage the thiol and disulphide levels in Helicobacter pylori-positive patients with non-ulcer dyspepsia and investigate the change in these levels with eradication therapy. Methods: This is a prospective observational study. A total of 320 patients diagnosed with dyspepsia according to Rome IV criteria were included in the study. First, blood samples were drawn from patients to determine their serum thiol and disulphide levels. Endoscopic biopsy was performed on all patients and the biopsy specimens obtained were examined pathologically. Patients positive for H. pylori were administered eradication therapy. Blood samples were drawn from these patients for the second time, and their serum thiol and disulphide levels were measured. The thiol–disulfide levels of the patients who were successful in H. pylori eradication treatment, with those who were not, were compared before and after the treatment. Results: The mean plasma disulphide level decreased significantly from 14.0 ± 6.6 to 10.9 ± 5.9 μmol/L in H. pylori-positive patients that responded to the H. pylori eradication treatment (P = 0.033). On the other hand, there was an insignificant increase in the mean serum thiol level (341.4 ± 30.5 vs. 342.6 ± 29.8 μmol/L; P = 0.273) and an insignificant decrease in the mean serum disulphide level (15.2 ± 2.5 vs. 14.8 ± 2.3 μmol/L; P = 0.163) in H. pylori-positive patients that did not respond to the H. pylori eradication treatment. Conclusion: The inflammation caused by H. pylori shifted the thiol–disulphide equilibrium in the cell redox system towards the direction of disulphide. The study findings suggest that the restoration of the said hemostatic balance with eradication therapy relieved the organism from oxidative stress.

INTRODUCTION: A hypercoagulability status has been reported in SARS-CoV-2 infection. Beside their traditional roles, platelets are referred to as immune cells. The purpose of the study was to examine platelet activation and aggregation in COVID-19. METHODS: This case-control study comprised 61 patients with SARS-CoV-2 infection and 18 healthy individuals. The patients were separated into groups with respect to the need for treatment in the intensive care unit (ICU). CD41, CD61, CD42a, and CD42b were determined as platelet activation markers, and platelet aggregation tests were analyzed in all groups. RESULTS: Platelet CD41, CD61, CD42a, and CD42b expressions were significantly elevated in ICU patients compared to non-ICU patients and healthy donors. Patients in the ICU group had increased platelet aggregations than those in non-ICU patients and controls. Additionally, platelet activation and platelet function tests correlated with inflammatory and coagulation markers involving C‐reactive protein, Interleukin-6, neutrophil-to-lymphocyte ratio, platelet‐to‐lymphocyte ratio, monocyte to lymphocyte ratio, D-dimer, and fibrinogen concentrations. DISCUSSION AND CONCLUSION: Enhanced platelet activity and faster platelet aggregation were observed in ICU COVID-19 patients. It is possible that platelet hyperreactivity may contribute to the progression of SARS-CoV-2 infection. The relationships between platelet activation and functions tests with inflammatory and coagulation markers show that systemic inflammation and cytokines may trigger the hypercoagulability in COVID-19 patients in ICU, or hyperactivated platelets could augment the inflammation.

Aim:Positron emission tomography/computerized tomography (PET/CT) is used for oncologic imaging as hybrid imaging. Pediatric patients are exposed to ionizing radiation when they undergo hybrid medical imaging examinations. It is especially important to minimize the radiation exposure when children and infants are imagined, as immature tissues are more susceptible to damage induced by radiation. This study aims to reveal the oxidant and antioxidant status in oncology patients before and after PET/CT imaging.Methods:Between February 2019 and July 2019, pediatric oncology patients who underwent PET imaging at the time of diagnosis in our center were included in the study. Eighteen newly diagnosed cancer pediatric patients participated in this prospective cross-sectional study. Data were saved to synchronously kept excel log files and used in the study. Disulphide amounts, total and native thiols, native thiol/total thiol percent ratios, disulphide/native thiol percent ratios, disulphide/total thiol percent ratios, and Ischemia-Modified Albumin were calculated before and after the PET/CT imaging.Results:Disulphide levels, disulphide/total thiol and disulphide/native thiol ratios of patients’ serum samples were significantly higher and the ratio of native thiol/total thiol was reduced after the PET/CT.Conclusion:There was disturbed thiol-disulfide homeostasis and the balance changed in the direction of oxidant damage. Our results indicate the possible oxidative stress condition due to radiation exposure with PET/CT in pediatric oncology patients.

We planned this study to research the effect of freeze-thaw number and storage temperatures on the tests of thiol-disulfide homeostasis. Dynamic thiol-disulfide homeostasis has a crucial role in antioxidant defense reactions. Thiol disulfide homeostasis is detected in serum samples. To gauge the steadiness at different storage temperatures, sera stored at -20°C and -80°C for 1, 2, 3, 6, and 12 months. To work out the effect of the freeze-thaw cycle, sera were frozen at -80°C and subjected to ten freeze-thaw cycles at 24-hour intervals. According to our results, native thiol, total thiol, and disulfide levels in human serum samples were stable at -20°C for three months and at -80°C for 12 months. After the third month at -20°C, native thiol and total thiol levels decreased while disulfide levels increased. Additionally, as the number of freeze-thaw cycles increased, native thiol and total thiol levels decreased, and disulfide levels increased. Our results show that storage at -20°C and an increasing number of freeze-thaw processes affect thiols levels. To get the most accurate results, repeated freeze-thaw cycles should be avoided the maximum amount possible. Also, samples should be frozen at -80°C if long storage times are required. [Med-Science 2021; 10(2.000): 450-4]

INTRODUCTION: To study changes in dynamic thiol/disulfide homeostasis (TDH) in patients with acute aortic dissection (AAD). METHODS: In our study, the medical records of patients who applied to Ankara Atatürk Training and Research Hospital between January 2015- January 2018 and were found to have AAD on computed tomography of the thorax were retrospectively reviewed. There were two groups in the study, one AAD group, and the other healthy volunteers' group. First, thiol and disulfide levels were determined with the spectrophotometric method defined by Erel and Neşelioğlu, natural thiol (NT), total thiol (TT), and disulfide (D) levels, and their ratios were calculated (index 1: D / NT, index 2: D / TT, index 3: NT / TT). We compared these two groups in terms of Oxidative stress parameters. RESULTS: A total of 40 patients with AAD and 38 age-matched healthy volunteers were included in this study. There was no significant difference between the two groups in terms of gender and age (p=0.923, p=0.401, respectively). The AAD group had significantly lower natural thiol and total thiol (p

Resumo Fundamento A espessura médio-intimal (EMI) da artéria aorta abdominal (EMI-A) pode ser um marcador precoce de aterosclerose subclínica e um indicador objetivo de estresse oxidativo em pacientes com talassemia menor. Objetivo Avaliar se as EMIs da artéria aorta e da artéria carótida (EMI-C) se alteram com estresse oxidativo, e examinar a relação entre esses parâmetros em pacientes com talassemia menor. Métodos O estudo incluiu 80 pacientes diagnosticados com talassemia menor, e 50 indivíduos sadios com idade e sexo similares. Após procedimentos de rotina, as amostras de sangue foram coletadas dos grupos de estudo para a medida da homeostase tiol/dissulfeto e da albumina modificada pela isquemia (AMI). As medidas da EMI-C foram realizadas a partir de quatro regiões diferentes (artéria carótida externa direita e esquerda e artéria carótida interna direita e esquerda) por ultrassonografia, e a medida da EMI-A foi realizada por ultrassonografia abdominal. Um valor de p

ABSTRACT Objective: Graves’ ophthalmopathy (GO) is a vision-threatening finding observed in approximately half of Graves’ disease patients. The pathophysiology of GO is unclear, and one of the suspected factors is oxidative stress. In our study, we compared the relationship between proptosis and SH-SS in patients diagnosed with GO. Materials and methods: In this prospective study, 40 recently diagnosed Graves’ disease patients with proptosis, 40 recently diagnosed Graves’ disease patients without GO and 30 healthy individuals with similar demographic characteristics were included. Serum thiol-disulfide (SH-SS) measurements were performed. Eye examinations were performed by a single ophthalmologist to check for the presence of GO, and proptosis values were recorded with a Hertel exophthalmometer. Results: Total SH values were lower in the group with proptosis than in the other groups (p < 0.05). Total and native SH values were lower in patients without proptosis than in the control group (p < 0.05). Total SH, native SH and SS levels were independently associated with proptosis (p < 0.05). According to this analysis, it was found that increasing SS and decreasing total and native SH levels increased the probability of proptosis by 24.4%, 32.7% and 32.4%, respectively. Conclusion: A decrease in SH, which is a natural antioxidant that protects the body against oxidative stress, and an increase in SS are important signs of oxidative damage. Proptosis and SH-SS are closely related in GO. This may help us detect GO and proptosis in Graves’ patients. It can also assist in developing new options for preventing and treating GO.

This study aimed to investigatethe possible association of thiol/disulfidehomeostasiswith prostate-specific antigen levelsin prostate cancer patients and to compare the results with a normal healthy population ofa similar age group for the first time in literature. Forty-twopatients (20 patientswith prostate cancer and 22 volunteers) were included in the study. Thiol/disulfide homeostasis tests were measured with an automated method. Albumin, carcinoembryonic antigen (CEA), prostate-specific antigen (PSA), ischemia modified albumin (IMA), total thiol (TT), native thiol (SH), and disulfide (SS) levelsand, thiol-disulfide ratios (disulfide / native thiol, disulfide/total thiol and native thiol/total thiol) were assessed to detect any differences between prostate cancer group and control group. The mean PSA value of the prostate cancer group was 2.56 ng/mL, the mean PSA value of the control group was 1.21 ng/mL, and the mean age of the prostate cancer group was 67.32 years, the mean age of control group was 60.09. Although native thiol and total thiol levels were significantly lower in patients with prostate cancer (p 0.05). In our study, we could not show thiol-disulfide values as a biochemical prognostic factor in patients with prostate cancer. We believe that serum TT, SH, SS concentrations cannot serve as a noninvasive biomarker for prostate cancer. To verify the biochemical role of thiol/disulfide balance, studies need to be done by increasing the number of patients with prostate cancer. [Med-Science 2020; 9(3.000): 779-83]

Abstract Background Telogen effluvium is the most common form of non-scarring alopecia characterized by diffuse hair loss. Ischemia-modified albumin is a marker of oxidative stress and inflammation. Objective The aim of this study was to compare the levels of ischemia-modified albumin of telogen effluvium patients with healthy controls. Methods Ninety-one patients diagnosed with telogen effluvium and 35 healthy volunteers were included in the study. Serum ischemia-modified albumin level was determined by a fast-colorimetric method, and albumin cobalt binding test. The results were evaluated statistically. Results There was no statistically significant difference between the serum albumin values of patient and control groups (p = 0.739). Serum ischemia-modified albumin values were significantly higher in the patients with telogen effluvium than healthy controls (p < 0.001). Study limitations Body mass index values of the patient and control groups could not be calculated. Conclusions To the best of the authors’ knowledge, this is the first clinical study to investigate the role of oxidative stress in the pathogenesis of telogen effluvium using ischemia-modified albumin as a biomarker. Based on the results of the present study, it can be considered that oxidative stress plays an important role in the pathogenesis of telogen effluvium. There is a need for further studies to support the results of this study, to demonstrate the possible effects of oxidative stress, and to investigate the other oxidative stress markers in the pathogenesis of telogen effluvium.

Thiol/disulfide homeostasis (TDH) is a new marker of oxidative stress. In this study, we would like to determine the changes in TDH in hemodialysis (HD) patients with chronic kidney disease (CKD). This cross-sectional study was conducted in the Nephrology Clinic of Konya Training and Research Hospital. A total of 197 individuals including 75 HD patients, 41 end stage renal disease (ESRD) patients (having stage 3-5 CKD but not receiving hemodialysis), and 81 healthy controls were enrolled in the study. Serum native thiol, total thiol, and disulfide levels were measured with a new method developed by Erel and Neselioglu. It was determined that there was a statistically significant difference in the mean age, body mass index (BMI), modification of diet in renal disease (MDRD), and creatinine level between the three groups (p [Med-Science 2020; 9(1.000): 201-4]

Amaç: Bu gözlemsel, prospektif, vaka kontrol çalışmasında erişkin hastalarda serum dinamik Tiyol-Disülfir Homeostazisi (TDH) ile sepsis arasındaki ilişkiyi araştırmayı amaçladık.Gereç ve Yöntem: Sepsis tanısı ile alan 44 hasta, yaş ve cinsiyet uyumlu 44 sağlıklı kontrol ile karşılaştırıldı. Hastalar yoğun bakım ünitesi yatışından sonraki 28. günde sağ-kalan ve hayatını kaybedenler olarak 2 gruba ayrıldı. TDH parametreleri yeni, otomatik ve spektrofotometrik bir yöntem kullanılarak ölçüldü ve sonuçlar istatistiksel olarak karşılaştırıldı.Bulgular: Sepsisli hastalarda, nativ tiyol, total tiyol ve disülfit seviyeleri kontrol grubuna göre daha düşük olarak bulundu ve bu fark istatistiksel olarak anlamlı idi. Başlangıç TDH parametreleri sağ-kalan ve hayatını kaybeden hastalar arasındaki benzer bulundu. Ancak sağ kalan ve ex olan hastaların 3 ve 7. günde tekrarlanan TDH ölçümleri (nativ ve toplam tiyol seviyeleri) arasında anlamlı farklar bulundu.Sonuç: Bu çalışma, erişkin sepsis hastalarında dinamik TDH'deki bozulmanın negatif sonuçlara ilişkili olabileceğini göstermiştir.

Purpose. Thiols are sulfhydryl-containing organic compounds that have an important role in preventing cellular oxidative stress. This study compares the blood oxidative stress marker levels in bronchiectasis cases during their stable periods with healthy controls. Materials and Methods. Seventy-seven patients (49 patients with stable bronchiectasis/28 healthy controls), followed up by the chest disease clinic, were included in the study. Peripheral blood thiol-disulfide parameters (NT: native thiol (−SH); TT: total thiol (−SH + SS); SS: disulfide (−SS); SS-SH: disulfide/native thiol index; SS-TT: disulphide/total thiol index; SH-TT: native thiol/total thiol index), and ischemia-modified albumin (IMA) levels were examined in the stable bronchiectasis group and the control group. Thiol-disulfide homeostasis was evaluated using a novel and automated assay. Findings and Result. Blood native thiol levels in patients with stable bronchiectasis were found to be significantly higher compared with healthy controls. A positive correlation between the total airway disease score and IMA levels was present. Our findings revealed that native thiol levels, which constitute a part of the antioxidant defense system, are increased in patients with stable bronchiectasis.

Objective: The mechanism of the leiomyoma formation process is still unknown. However, the menstrual cycle is associated with hypoxia, and ongoing hypoxia is associated with cellular events leading to the conversion of myometrial cells into uterine fibroids. After the hypoxic environment, the balance of cellular cytokines and growth factors changes. It was planned to evaluate the balance of oxidative agents and the role of oxidative stress in the formation of uterine fibroids. Study Design: The study was conducted in patients of gynecology outpatient clinic of Ankara Oncology Training and Research Hospital. Those volunteers with fibroids formed the study group, and the healthy ones were identified as the control group. A total of 64 subjects, 32 in both groups were included. The levels of catalase, ceruloplasmin, myeloperoxidase, native thiol, disulfide, and total thiol levels were investigated in groups. Results: Antioxidant parameters such as native thiol, disulfide, and total thiol levels were significantly decreased in uterine fibroid group. Catalase, ceruloplasmin, and myeloperoxidase levels were not statistically different between groups. Conclusion: Decrease in these antioxidant parameters showed that the hypoxia and the balance of oxidant and antioxidant substances changes may probably have associated with the pathophysiology of uterine fibroids.

INTRODUCTION[|]Contrast-induced nephropathy (CIN) is a common complication of diagnostic or interventional procedures that may arise from administration of intravascular contrast media. Recent studies have reported the thiol-disulfide ratio as a novel oxidative stress marker. Therefore, we investigated the role of thiol levels in predicting CIN in patients with ST-segment elevation myocardial infarction (STEMI) who had undergone primary percutaneous coronary intervention (PCI).[¤]METHODS[|]A total of 302 patients were enrolled in the study. CIN was defined as an increase in serum creatinine concentration ≥0.5 mg/dL compared with the admission value or a >25% relative rise during the first 48–72 hours after the procedure. To evaluate the relationship between thiol levels and CIN, the patients were divided into a CIN group and a non-CIN group.[¤]RESULTS[|]CIN occurred in 44 (15%) patients. Native thiol (274.8+-84.7 μmol/L vs. 220.8+-97.1 μmol/L, p=0.001) and total thiol (305.4+-89.7 μmol/L vs. 260.1+-102.1 μmol/L, p=0.009) levels were higher in patients within the non-CIN group. Disulfide (15.8+-6.6 μmol/L vs. 19.6+-8.4 μmol/L, p=0.002) levels, and mean disulfide/total thiol ratios (8.4+-3.7 vs. 5.9+-3.1, p=0.001) were higher in patients with CIN (+) group. In univariate analysis, the initial native thiol, total thiol, disulfide levels, and disulfide/total thiol ratio were found to have prognostic significance in the development of CIN. In the multivariate regression analysis, only the disulfide/total thiol ratio (OR=1.190; 95% CI: 1.090–1.300; p=0.001) was significantly and independently associated with CIN. The cutoff value of the disulfide/total thiol ratio to predict CIN on admission in patients with STEMI who underwent primary PCI was 7, with a sensitivity of 68.2% and a specificity of 79.8%.[¤]DISCUSSION AND CONCLUSION[|]Our results suggest that thiol/disulfide homeostasis could be a good biochemical risk marker for CIN in STEMI patients who underwent primary PCI.[¤]

Purpose: A dynamic thiol/disulfide balance is pivotal in organizing anti-oxidant defense, detoxification, apoptosis, and enzyme activities, as well as transcription and cellular signal-transfer mechanisms. The connection between urolithiasis and oxidant/antioxidant status, which can be assessed through thiol-disulfide homeostasis (TDH), has not yet been examined. In this study, we evaluated the effects of TDH on the formation, size, and location of stones by examining the associations between TDH parameters and urolithiasis. Materials and Methods: Patients with urolithiasis and healthy controls were recruited. The patients were divided into subgroups in terms of stone size (>15 mm or ≤15 mm) and stone location (nephrolithiasis or ureterolithiasis). TDH parameters were measured using a novel automatic and spectrophotometric method and compared statistically. Results: TDH parameters were different between the urolithiasis and control groups. TDH tended towards the disulfide side in the urolithiasis group. Stone size increased an average 0.14 mm with a 1 µmol/L increase in disulfide level and decreased an average 0.058 mm with a 1 µmol/L increase in native thiol level. Disulfide and native thiol levels were found to be different across patients with stone size >15 mm, ≤15 mm, and controls (p

Background: Fibromyalgia syndrome (FMS) is an extra-articular rheumatological disease, characterized by widespread pain and somatic symptoms. The etiology has not yet been clarified. Oxidative stress may play an important role in FMS etiology. Thiol group is a very strong antioxidant. We aimed to investigate whether thiol/disulfide homeostasis in FMS is altered or not. Material and methods: A total of 80 female FMS patients and 64 healthy female control individuals were included in this study. Thiol and disulfide values were measured by Erel’s novel methods. Results: Native thiol (330.6 ± 46.1 vs. 356.8 ± 55.5 μmol/L, p = 0.005) and native thiol/total thiol (89.4 ± 3.2 vs. 93.3 ± 4.0, p < 0.001) levels of FMS patients were significantly lower when compared to the values of control group. However, disulfide (19.4 ± 6.3 vs. 12.2 ± 6.3 μmol/L, p < 0.001) levels of FMS patients were significantly higher than healthy individuals. A negative correlation was found between the native thiol/total thiol and fibromyalgia impact questionnaire (FIQ) score among the FMS patients. A positive correlation was found between disulfide values and FIQ score among the patients. Conclusions: In FMS patients, there was a significant correlation between the decrease in the thiol levels and an increase in the disulfide levels with the FIQ scores. We determined that thiol-disulfide rate was deteriorated in FMS patients and it increases in favor of disulfide amounts.

Background: Oxidative damage is of great importance for patients with breast cancer. Thus, studies were performed to identify the relationship between breast cancer and oxidative stress biomarkers.

Introduction: Idiopathic sudden sensorineural hearing loss (ISSNHL) isan otologic emergency that can lead to loss of function in one of the mostimportant human senses. Recently, hyperbaric oxygen therapy (HBOT) has gainedpopularity with pharmacotherapy in ISSNHL. This study aimed to determinechanges induced in thiol/disulfide homeostasis (TDH, a new biomarker ofsystemic oxidative stress) by pharmacotherapy and HBOT in patients with ISSNHL.Methods: This prospectivestudy analyzed the albumin, total thiol, native thiol, and disulfide levels anddisulfide-native thiol, disulfide-total thiol, and native thiol-total thiolratios before and after HBOT with standardizing pharmacotherapy using a newcolorimetric method in patientswith ISSNHL.Results: 41 patients withISSNHL including 14 (34.1%) women and 27 (65.9%) men participated in the study.The mean age of the patients was 48.02 ± 13.10 years. Of them, 24 (58.5%) hadhearing loss in the right ear and 17 (41.5%) had hearing loss in the left ear.There was a statistically significant decrease in the albumin (p lt;0.001),total thiol (p lt;0.001), native thiol (p lt;0.001), and disulfide (p lt;0.001)levels after treatment compared to baseline. There was no statisticallysignificant difference in the disulfide-native thiol (p=0.148), disulfide-totalthiol (p=0.172), and native thiol-total thiol (p=0.169) ratios after treatmentcompared to baseline.Conclusion: Consequently,this study demonstrated that the thiol-disulphide balance tended to shifttowards the oxidative side after HBOT and pharmacotherapy compared to baseline in patients with ISSNHL andthat patients with high oxidation level after treatment had better treatmentresponse.

Background: Gastric cancer is one the most diagnosed cancer and the third leading cause of death from cancer worldwide. As an indicator of antioxidant capacity thiol/disulfide homeostasis regulates detoxification, cell signal mechanisms, apoptosis, transcription and antioxidant defense mechanisms. Disregulation of thiol/disulfide homeostasis identified in other cancer types by recent data. In this study, we aimed to evaluate the thiol/disulfide homeostasis in advanced gastric cancer patients. Methods: The patients who diagnosed with gastric cancer and healthy control subjects were included to study. Serum samples for the thiol-disulphide test were obtained at the time of diagnosis. Thiol-disulphide homeostasis tests were measured by the automated spectrophotometric method. Thiol-disulphide homeostasis was also measured according to clinical and laboratory features. Results: Thirty newly diagnosed advanced gastric adenocarcinoma patients and 28 healthy controls were enrolled in the study. The native thiol (NT) and total thiol (TT) levels of patients' group were significantly lower compared with controls (p = 0.001 and p

Background: Vitiligo is a depigmenting cutaneous disorder with complex pathogenesis. Thiol compounds are well-known organic structures that play a major role in melanogenesis. Aim: The aim of this study was to determine the association between plasma thiol level and disease severity in patients with nonsegmental vitiligo. Methods: A total of 73 patients with nonsegmental vitiligo (57 generalized and 16 localized type) and age- and sex-matched 69 healthy controls were enrolled in the study. Plasma levels of native thiols, disulfides, and total thiols were measured by a novel and automated assay. Disease severity of vitiligo was assessed with Vitiligo Area Scoring Index (VASI) score. The extent, stage, and spread of vitiligo of patients were evaluated according to the Vitiligo European Task Force (VETF) system. Results: The native and total thiol levels of vitiligo patients were higher than those of healthy control group (P≤0.001 and 0.001, respectively). The median VASI score of patients was 0.7 (0.02–28.30). Univariate analyses showed that plasma native thiol levels, VETF spread score, disease duration, and vitiligo type significantly correlated with VASI scores (r=0.237, P=0.043; r=0.458, P

This work aimed to evaluate the thiol-disulphide homeostasis in serum of lambs naturally infected by gastrointestinal nematodes presenting different levels of parasite load indirectly indicated by faecal worm egg counts (EPG). Furthermore, the possible changes in the thiol-disulphide dynamic after different procedures to reduce the parasitic charge, such as the integrated crop-livestock system or anthelmintic treatment, were assessed. The results were compared with a panel of various oxidative stress and inflammatory biomarkers. The lambs were divided into three groups: animals highly infected (EPG higher than 5000) and packed cell volume (PCV) lower than 24% (G1); animals highly infected (EPG higher than 5000) and normal PCV (>24%) (G2); and animals presenting EPG lower than 5000 and normal PCV (>24%) (G3). The highly infected lambs (G1 and G2) showed lower total thiol (TT) and native thiol (SH) (p ≤ 0.01) than those from G3. After treatment, TT and SH increased significantly in all groups (p ≤ 0.01), and the disulphide (SS)/TT and SS/SH ratios decreased significantly (p < 0.01) in G1 and G2. These results show that the thiol-disulphide balance was impaired in lambs infected by gastrointestinal nematodes and that it could be potentially used as a biomarker to monitor this disease.

Background: Rosacea is an inflammatory skin disease of face. In recent years, it is revealed that imbalance is significant in oxidant/antioxidant system in pathophysiology. Objective: In this study, the role of oxidative stress on rosacea was investigated. Methods: 34 rosacea patients and 33 healthy control cases between 18 and 70 years old are included in the study. In all the cases, serum lipids, Paraoxonase1(PON1), stimulated Paraoxonase1(stPON1), Arylesterase(ARES), Total Oxidant Status (TOS) and Total Antioxidant Status (TAS) levels are measured. Results: ARES levels were significantly lower and TOS levels were significantly higher in the patient group (p

Objectives: A water pipe (hookah) is a tobacco smoking tool which is thought to be more harmless than a cigarette, and there are no adequate studies about its hazards to health. Water-pipe smoking is threatening health of the youth in the world today. The objective of this study has been to investigate the carbon monoxide (CO) levels in breath, examine the changes in pulmonary function tests (PFT) and to assess the change of the oxidative stress parameters in blood after smoking a water pipe. Material and Methods: This study is a cross-sectional analytical study that has included 50 volunteers who smoke a water pipe and the control group of 50 volunteers who smoke neither a cigarette nor a water pipe. Carbon monoxide levels were measured in the breath and pulmonary function tests (PFTs) were performed before and after smoking a water pipe. Blood samples were taken from either the volunteer control group or water-pipe smokers group after smoking a water pipe for the purpose of evaluation of the parameters of oxidative stress. Results: Carbon monoxide values were measured to be 8.08±7.4 ppm and 28.08±16.5 ppm before and after smoking a water pipe, respectively. This increment was found statistically significant. There were also significant reductions in PFTs after smoking a water pipe. Total oxidative status (TOS), total antioxidant status (TAS) and oxidative stress index (OSI) were found prominently higher after smoking a water pipe for the group of water-pipe smokers than for the control group. Conclusions: This study has shown that water-pipe smoking leads to deterioration in pulmonary function and increases oxidative stress. To the best of our knowledge this study is the only one that has shown the effect of water-pipe smoking on oxidative stress. More studies must be planned to show the side effects of water-pipe habit and protective policies should be planned especially for young people in Europe. Int J Occup Med Environ Health 2017;30(5):731–742

Abstract: Purpose: To investigate the microbiological, inflammatory and oxidant effects of adjuvant ozone administration in experimental rat vascular graft infection model which has not been previously investigated. Methods: Forty adult Wistar rats were divided into Sham, Control, Vancomycin, Ozone, Vancomycin+Ozone groups. Grafts were inoculated with Methicillin-resistant Staphylococcus aureus (MRSA) strain and implanted subcutaneously. Rats were treated intraperitoneally with ozone and /or intramuscularly with vancomycin for 10 days. Grafts were evaluated by quantitative bacterial cultures. Blood samples were harvested for determination of thiol-disulphide and cytokine profiles. Results: There was no significant difference in bacterial counts between Control and Ozone Groups. In the Ozone Group median colony count was significantly higher than the Vancomycin and Vancomycin+Ozone Groups. Total thiol and disulphide levels increased and disulphide/native thiol and disulphide/total thiol ratios decreased in Ozone Group significantly. Albumin levels decreased significantly in Vancomycin and Vancomycin+Ozone Groups compared to the Sham Group. IL-1 and TNF-alpha levels significantly increased in infected rats. Decreased levels of VEGF due to infection reversed by ozone therapy in control and vancomycin groups. Conclusions: We didn't observe any benefit of the agent on MRSA elimination in our model. Likewise, effects of ozone on thiol-disulphide homeostasis and inflammatory cytokines were contradictory.

Abstract: We studied dynamic thiol/disulphide homeostasis, an indicator of oxidative stress, to investigate the effects of newly initiated exercise training on sedentary obese adults. Seventeen sedentary obese adults and 15 normal-weight controls were included in the sample for this study. The obese adults were given a physical exercise training program that lasted twelve weeks. Before and after the exercise training program, blood samples were collected, and serum thiol/disulphide parameters were measured by using a novel technique. Before the start of the exercise training, it was observed that thiol/disulphide homeostasis was impaired, and this impairment was positively correlated with body mass index in sedentary obese adults because of the higher reactive oxygen species production in adipose tissue. However, while the obese participants’ body mass index significantly decreased, the thiol/disulphide homeostasis parameters in the obese adults did not change over time as calculated at the baseline and compared to the calculation after the twelve weeks of exercise training. Despite a decrease in body mass index that occurred after the twelve weeks of exercise training, there was a lack of improvement in the obesity-induced impairment of thiol/disulphide homeostasis, which suggests that a newly initiated exercise training program may lead to oxidative stress.

Background: We aimed to investigate the effects of general, spinal and epidural anesthesia on fetal total antioxidant status (TAS) and total oxidant status (TOS), and oxidative stress index (OSI) during elective cesarean section in this study. Materials and Methods: Forty-seven parturients scheduled for elective cesarean section were randomly allocated into three groups: Group spinal (n = 15), group epidural (n = 17), and group general (n = 15), This prospective randomized study was performed in Faculty of Medicine, Turgut Ozal University, Turkey. After the baby was delivered; TAS, TOS levels, and arterial blood gases parameters were analyzed in an umbilical arterial blood sample. OSI values are calculated by a ratio of TOS to the TAS. Results: The levels of TAS and TOS in umbilical arterial blood sample were not statistically different among three. However, OSI values were significantly different among the three groups (P = 0.042). Median OSI values is 24 (interquartile range [IQR], 2-37) in group spinal, 19 (IQR, 4-44) in group epidural, and 8 (IQR, 4-36) in group general. There was no significant difference in OSI values in the comparison of group spinal with group general and group epidural, but it was significantly lower in group general when compared with group epidural with Bonferroni correction (P = 0.017). Umbilical cord arterial blood gas values (pH, PaCO 2 , PaO 2 , SaO 2 , HCO 3 , and CtO 2 ), glucose, lactate, and hemoglobin levels were similar in three groups. Conclusion: General anesthesia may be more favorable than epidural in those undergoing cesarean section when fetal oxidative status gains importance.

Background and objectives: The aim of this study was to research oxidative stress and thiol/disulphide homeostasis in Graves’ patients. Materials and Methods: The study included 33 Graves’ patients (research group) and 35 healthy subjects (control group). Serum oxidative stress and thiol/disulphide homeostasis (a new and automated spectrophotometric method developed by Erel and Neselioglu) parameters were studied and compared between the groups. Results: The native and total thiol levels and the native thiol/total thiol ratio were lower in patients with Graves’ disease compared to the control group (p < 0.001, p < 0.001, and p = 0.006, respectively). TOS (total antioxidant status), PC (protein carbonyl), OSI (Oxidative stress index), and disulphide/native thiol and disulphide/total thiol ratios were determined to be higher in the Graves’ disease group than in the control group (p < 0.001, p = 0.001, p = 0.001, p = 0.004, and p = 0.006, respectively). In the Graves’ disease group, the free triiodothyronine (FT3) and free thyroxine (FT4) levels were significantly positively correlated with impaired thiol/disulphide homeostasis and oxidative stress parameters (p < 0.05). Conclusion: The results of the current study demonstrated that oxidative stress and thiol/disulphide homeostasis increased towards disulphide formation due to thiol oxidation in Graves’ disease. In addition, a positive correlation of FT3 and FT4 was observed with oxidative stress parameters and impaired thiol/disulphide homeostasis.

OBJETIVO: O estresse oxidativo demonstrou contribuir para a patogênese de doenças pulmonares inflamatórias agudas e crônicas. Nosso objetivo foi avaliar o estado oxidante/antioxidante de crianças com bronquiolite aguda por meio de mensuração da capacidade antioxidante total do plasma, estado oxidante total e índice de estresse oxidativo. MÉTODOS: As crianças com bronquiolite aguda encaminhadas para o Departamento de Emergência Pediátrica do hospital universitário entre janeiro e abril 2012 foram comparadas a controles saudáveis de mesma idade. Os pacientes com bronquiolite aguda tiveram essa doença classificada como leve e moderada. O estado oxidante e antioxidante foi avaliado pela mensuração da capacidade antioxidante total do plasma, estado oxidante total e índice de estresse oxidativo. RESULTADOS: Foram incluídas 31 crianças com bronquiolite aguda com idade de três meses a dois anos e 37 crianças saudáveis. O estado oxidante total (EOT) foi maior em pacientes com bronquiolite aguda do que no grupo de controle (5,16±1,99 µmol H2O2 em comparação a 3,78±1,78 µmol H2O2 [p = 0,004]). A capacidade antioxidante total (CAT) foi significativamente menor em crianças com bronquiolite que no grupo de controle (2,51±0,37 µmol Trolox equivalente/L em comparação a 2,75±0,39 µmol Trolox Eqv/L) (p = 0,013). Os pacientes com bronquiolite moderada apresentaram níveis de EOT mais elevados que os com bronquiolite leve e os do grupo de controle (p = 0,03, p < 0,001). Os pacientes com bronquiolite moderada apresentaram níveis de IEO mais elevados que os do grupo de controle (p = 0,015). O nível de saturação de oxigênio de pacientes com bronquiolite foi inversamente correlacionado ao nível de EOT (r = -0,476, p < 0,05). CONCLUSÃO: O equilíbrio entre os sistemas oxidante e antioxidante é interrompido em crianças com bronquiolite moderada, indicando que o fator de estresse poderá ter um papel na patogênese da doença.

Objective: Oxidative stress has been shown to contribute to the pathogenesis of acute and chronic lung inflammatory diseases. This article aimed to evaluate the oxidant/antioxidant status of children with acute bronchiolitis through the measurement of plasma total antioxidant capacity, total oxidant status, and oxidative stress index. Methods: Children with acute bronchiolitis admitted to the pediatric emergency department of a university hospital between January and April of 2012 were compared with agematched healthy controls. Patients with acute bronchiolitis were classified as mild and moderate bronchiolitis. Oxidative and antioxidative status were assessed by measurement of plasma total antioxidant capacity, total oxidant status, and oxidative stress index. Results: Thirty-one children with acute bronchiolitis aged between 3 months and 2 years, and 39 healthy children were included. Total oxidative status (TOS) was higher in patients with acute bronchiolitis than the control group (5.16±1.99 μmol H2O2 versus 3.78±1.78 μmol H2O2 [p = 0.004]). Total antioxidant capacity (TAC) was lower in children with bronchiolitis than the control group (2.51±0.37 μmol Trolox eqv/L versus 2.75±0.39 μmol Trolox eqv/L [p = 0.013]). Patients with moderate bronchiolitis presented higher TOS levels than those with mild bronchiolitis and the control group (p = 0.03, p

Aim. To investigate the role of a novel oxidative stress marker, thiol/disulphide homeostasis, in patients diagnosed with acute appendicitis (AA). Methods. In this study, seventy-one (43 male and 28 female) patients diagnosed with AA and 71 (30 male and 41 female) healthy volunteers were included. Age, gender, body mass index (BMI), haemoglobin (Hb), white blood cell (WBC), c-reactive protein (CRP), and thiol/disulphide homeostasis parameters (native thiol, total thiol, disulphide, disulphide/native thiol, native thiol/total thiol, and disulphide/total thiol ratios) were compared between the groups. Thiol/disulphide homeostasis was determined by a newly developed method by Erel and Neselioglu. Results. The native thiol, total thiol, and the native thiol/total thiol ratio levels were statistically significantly decreased in the AA compared with the control group (p

OBJETIVOS: Estudar o efeito do fumo passivo sobre o estado plasmático oxidativo e antioxidativo em pré-escolares fumantes passivos e compará-los com controles. MÉTODOS: Trinta e quatro pré-escolares fumantes passivos (cinco a 50 cigarros/dia) (grupo de estudo) e 32 controles que nunca estiveram expostos à fumaça de cigarro foram escolhidos aleatoriamente entre crianças de 4 a 6 anos. Foram determinados os níveis de cotinina urinária e de indicadores do estado oxidativo e antioxidativo, isto é, estado oxidante total (EOT), capacidade antioxidante total (CAT) e índice de estresse oxidativo (IEO). RESULTADOS: A média do consumo ambiental de cigarros foi de 22±13 cigarros por dia nas crianças fumantes passivas. Os níveis médios de cotinina urinária foram 77,6±41,4 ng/mL e 11,9±2,3 ng/mL nos grupos de estudo e controle, respectivamente (p < 0,001). Os níveis médios da CAT plasmática foram 0,95±0,13 mmol equivalente de Trolox/L e 1,01±0,09 mmol equivalente de Trolox/L, respectivamente (p = 0,039). Os níveis médios de EOT plasmático foram 28,6±7,9 µmol H2O2 equivalente/L e 18,5±6,3 µmol H2O2 equivalente/L, respectivamente (p < 0,001). Os níveis médios de IEO foram 3,08±0,98 unidade arbitrária e 1,84±0,64 unidade arbitrária, respectivamente (p < 0,001). Uma pequena quantidade de fumaça de cigarro (cinco a 10 cigarros/dia) causa estresse oxidativo considerável. Não houve correlações significativas entre o número de cigarros consumidos e os níveis de estado oxidante e de IEO. CONCLUSÕES: O tabagismo passivo é um potente oxidante em pré-escolares. Seus efeitos deletérios não se limitam apenas tabagismo passivo pesado, mas também ocorrem com a exposição a pequenas quantidades de fumaça.

Total antioxidant status (TAS), total oxidant status (TOS), as well as total phenol (TP), free phenol (FP), conjugated phenol (CP), and the vitamin C content of pepper plants (Capsicum annuum cv. ‘Charlee’) infected with Pepper mild mottle virus (PMMoV) were determined via a novel automated antioxidant system using test kits. PMMoV was first identified in Turkey in 1994 in commercial pepper (Capsicum annuum cv. ‘Charlee’) fields and caused an outbreak in southern Turkey by 2006, especially in greenhouses. Infected plants were confirmed by ELISA using commercial kits for the virus. The infected plants had stunted growth; and leaves and fruits became mottled, puckered, malformed, deformed, and marked by off-colored sunken areas. Fruits expressing virus symptoms were utilized for biochemical analyses. The percent ratio of TOS to TAS was calculated as the oxidative stress index (OSI). The TAS level and the vitamin C content were found to be significantly lower in infected peppers as compared to healthy peppers. However, TOS, OSI, TP, FP, and CP levels were significantly higher in infected pepper fruits than in healthy ones. In this study, it has been demonstrated that low levels of TAS and high levels of TOS, as well as high OSI status, reflects the quality of peppers. Using this method, the quality of fruits and the condition of plants can be determined in advance of stress development.

OBJETIVO: Determinar se a fita de DNA de leucócitos mononucleares endógenos é alvo de fototerapia. MÉTODOS: O estudo incluiu 65 recém-nascidos a termo com idades entre 3 e 10 dias que haviam sido expostos a fototerapia intensiva (n = 23) ou convencional (n = 23) por pelo menos 48 horas devido à icterícia neonatal, além de um grupo controle (n = 19). Dano ao DNA foi avaliado por eletroforese alcalina em gel de célula única (ensaio cometa). A capacidade antioxidante total plasmática e os níveis de estado oxidativo total também foram medidos, e a correlação entre danos ao DNA e estresse oxidativo foi investigada. RESULTADOS: Os valores médios de escores de danos ao DNA nos grupos de fototerapia intensiva e convencional foram significativamente maiores do que os do grupo controle (p < 0,001). Os valores médios e desvio padrão foram 32 (9), 28 (9), 21 (7) unidades arbitrárias, respectivamente. Os níveis de estado oxidativo nos grupos de fototerapia intensiva e convencional foram significativamente maiores do que os do grupo controle (p < 0,005). Os valores médios (desvio padrão) foram 18, 1 (4,2), 16.9 (4,4), 13,5 (4,2) µmol H2O2 equivalente/L, respectivamente. De maneira semelhante, os níveis de estresse oxidativo nos grupos de fototerapia intensiva e convencional foram significativamente maiores do que os do grupo controle (p = 0,041). A capacidade antioxidante total plasmática e os níveis de bilirrubina total não diferiram entre os grupos (p > 0,05). Não houve correlações significativas entre escores de danos ao DNA e bilirrubina, estado oxidante total e níveis de estresse oxidativo entre os grupos de fototerapia (p > 0,05). CONCLUSÕES: Tanto a fototerapia intensiva quanto a convencional causam danos ao DNA dos leucócitos mononucleares endógenos em recém-nascidos a termo com icterícia.OBJECTIVE: Our aim was to determine whether endogenous mononuclear leukocyte DNA strand is a target of phototherapy. METHODS: The study included 65 term infants aged between 3-10 days that had been exposed to intensive (n = 23) or conventional (n = 23) phototherapy for at least 48 hours due to neonatal jaundice, and a control group (n = 19). DNA damage was assayed by single-cell alkaline gel electrophoresis (comet assay). Plasma total antioxidant capacity and total oxidant status levels were also measured, and correlation between DNA damage and oxidative stress was investigated. RESULTS: Mean values of DNA damage scores in both the intensive and conventional phototherapy groups were significantly higher than those in the control group (p < 0.001). Mean values and standard deviation were 32 (9), 28 (9), 21 (7) arbitrary unit, respectively. Total oxidant status levels in both the intensive and conventional phototherapy groups were significantly higher than those in the control group (p = 0.005). Mean (standard deviation) values were 18.1 (4.2), 16.9 (4.4), 13.5 (4.2) µmol H2O2 equivalent/L, respectively. Similarly, oxidative stress index levels in both the intensive and conventional phototherapy groups were significantly higher than those in the control group (p = 0.041). Plasma total antioxidant capacity and total bilirubin levels did not differ between the groups (p > 0.05). There were no significant correlations between DNA damage scores and bilirubin, total oxidant status and oxidative stress levels in either phototherapy group (p > 0.05). CONCLUSIONS: Both conventional phototherapy and intensive phototherapy cause endogenous mononuclear leukocyte DNA damage in jaundiced term infants.

OBJETIVO: Avaliar o efeito da fototerapia no estado oxidante e antioxidante no soro de recém-nascidos a termo com hiperbilirrubinemia. MÉTODO: Trinta e quatro recém-nascidos a termo com idades entre 3 e 10 dias submetidos a fototerapia foram avaliados. O estado antioxidante do soro foi determinado pela capacidade antioxidante total e por componentes antioxidantes individuais: vitamina C, ácido úrico, albumina, concentração de tiol e bilirrubina total. O estado oxidante foi avaliado através do estado oxidante total, índice de estresse oxidativo e componentes oxidantes individuais: malondialdeído e níveis de hidroperóxido lipídico. RESULTADOS: As concentrações de vitamina C, ácido úrico, bilirrubina total e malondialdeído foram significativamente mais baixas, enquanto que o estado oxidante total, níveis de hidroperóxido lipídico e o índice de estresse oxidativo foram significativamente maiores após a fototerapia (p < 0,05). Houve correlações positivas significativas entre a bilirrubina sérica total e a concentração de malondialdeído (r = 0,434, p = 0,001). CONCLUSÕES: Embora a concentração de malondialdeído tenha diminuído após a fototerapia, esta exerce um efeito negativo sobre as diversas partes do sistema de defesa oxidante/antioxidante em recém-nascidos a termo ictéricos, expondo-os a um possível estresse oxidativo.OBJECTIVE: To assess the effect of phototherapy on serum oxidant and antioxidant status in hyperbilirubinemic full-term newborns. METHOD: Thirty-four full-term infants from 3 to 10 days of age exposed to phototherapy were studied. The serum antioxidant status was assessed by measuring the total antioxidant capacity (TAC) and individual antioxidant components: vitamin C, uric acid, albumin, thiol contents and total bilirubin. The oxidant status was assessed by determining the total oxidant status (TOS), oxidative stress index (OSI) and individual oxidant components: malondialdehyde (MDA), and lipid hydroperoxide levels. RESULTS: Vitamin C, uric acid, total bilirubin and MDA concentration were significantly lower, whereas serum TOS, lipid hydroperoxide and OSI levels were significantly higher after phototherapy (p < 0.05). There were significant positive correlations between serum total bilirubin and MDA (r = 0.434, p = 0.001). CONCLUSIONS: Although the MDA level was reduced after phototherapy, phototherapy has a negative impact on numerous parts of the oxidant/antioxidant defense system in jaundiced full-term newborns, exposing them to potential oxidative stress.

Background. Diabetic retinopathy (DR) is the leading cause of blindness in the world. Retinopathy can still progress despite optimal metabolic control. The aim of the study was to determine whether different degrees of DR (proliferative or nonproliferative) were associated with abnormally modulated hemostatic parameters in patients with T1DM. Method. 52 T1DM patients and 40 healthy controls were enrolled in the study. Patients were subdivided into three categories. Group I was defined as those without retinopathy, group II with NPRP, and group III with PRP. We compared these subgroups with each other and the control group (Group IV) according to the serum fibrinogen, plasminogen, alpha2-anti-plasmin (α2-anti-plasmin), and PAI. Results. We detected that PAI-1, serum fibrinogen, and plasminogen levels were similar between the diabetic and control groups (P=0.209, P=0.224, and P=0.244, resp.), whereas α2-anti-plasmin was higher in Groups I, II, and III compared to the control group (P

We compared the diagnostic performance characteristics of newly developed method, the rapid dipstick test, which provides colorimetric determination by developing antibody to the lactate dehydrogenase enzyme of parasites, with conventional standard thick-blood film examination. For the rapid test, OptiMAL commercial kits were used. The results were also evaluated with clinical findings from patients. The parasites were determined by microscopic examination of thick-blood films from 81 patients with vivax malaria from southeastern Anatolia, Turkey. The OptiMAL test results were found to be negative in five patients who were diagnosed clinically and through thick-film testing as having vivax malaria. There was no false positivity observed with the OptiMAL test. We concluded that this rapid malaria test has a lower level of sensitivity than the classical thick-blood-film test for malaria, but that these methods have equal specificity.

The metabolisms of reactive nitrogen and oxygen intermediates (RNI and ROI) in patients with cutaneous leishmaniasis (CL) were investigated and compared with those of healthy subjects. To determine RNI metabolism, nitrite plus nitrate concentrations were measured spectrophotometrically. Nitrite concentration in plasma was determined directly by the Griess method. Nitrate levels in plasma were measured after reduction into nitrite by using copper-cadmium-zinc. ROI metabolism was evaluated by measuring erythrocyte superoxide dismutase, catalase and glutathione peroxidase activities. Plasma nitrite plus nitrate levels and erythrocyte superoxide dismutase activity were higher in the patient group than healthy subjects (p

Background: Pityriasis rosea (PR) is usually an asymptomatic and self-limiting papulosquamous skin disease with acute onset. The etiology has not been clarified yet. Recently, increased oxidative stress was found to play a role in etiopathogenesis of multiple cutaneous diseases with T cell-mediated immune response. However, there are no studies demonstrating the oxidative stress status in PR. Aim: The aim of the study is to determine the status of oxidative stress (OS) and paraoxonase (PON) 1/arylesterase enzyme activities in PR. Materials and Methods: Study included 51 patients with active PR lesions, and 45 healthy volunteers. Serum levels of total oxidant status (TOS), total antioxidant status (TAS), and PON1/arylesterase (ARES) activity were determined and oxidative stress index (OSI) was calculated in all patients and controls. Results: TAS levels and ARES activities in the patient group were significantly lower than the control group. On the other hand, TOS and OSI levels were significantly higher in patients compared with controls. There was no significant correlation between the duration of disease and TAS, TOS, OSI levels, and ARES activities. Conclusion: A systemic oxidative stress exists in PR, which suggests that OS may be involved in the etiopathogenesis of disease.

Abstract Objective: To investigate the effect of continuous lung ventilation with low tidal volume on oxidation parameters, such as thiol/disulphide homeostasis and albumin-adjusted ischemia-modified albumin (AAIMA), during cardiopulmonary bypass (CBP) in coronary artery bypass grafting (CABG). Methods: Seventy-four patients who underwent elective CABG with CPB were included in the study. Blood samples were taken in the preoperative period, 10 minutes after CPB, and six and 24 hours postoperatively. Patients were assigned to the continuous ventilation group (Group 1, n=37) and the non-ventilated group (Group 2, n=37). The clinical characteristics, thiol/disulphide homeostasis, ischemia-modified albumin (IMA), and AAIMA levels of the patients were compared. Results: A significant difference was found between the groups regarding native thiol, total thiol, and IMA levels at the postoperative 24th hour (P=0.030, P=0.031, and P=0.004, respectively). There was no difference between the groups in terms of AAIMA. AAIMA levels returned to preoperative levels in Groups 1 and 2, at the 6th and 24th postoperative hours, respectively. Length of hospital stay was significantly shorter in Group 1 (P

Oxidative stress can be defined as an increase in oxidants and/or a decrease in antioxidant capacity. We aimed to determine total antioxidant capacity (TAC), total peroxide, malondialdehyde and catalase levels in plasma samples, and calculation of oxidative stress index (OSI) in patients with brucellosis to evaluate their oxidative status using a novel automated method. Sixty-nine patients with brucellosis and 69 healthy control subjects were included in the present study. Plasma levels of total peroxide and malondialdehyde were significantly increased in patients as compared with healthy controls (p0.05). OSI level was significantly increased in patients as compared with healthy controls (p

Abstract Background Thiol-disulfide homeostasis (TDH) plays a pivotal role in various physiological mechanisms, including antioxidant defence, detoxification, apoptosis, regulation of enzyme activities and cellular signal transduction. TDH can be used as a biomarker to detect oxidative stress (OS) levels and ischemia status in the tissues. Coronary artery bypass grafting (CABG) surgery is a procedure associated with high oxidative stress. Dexmedetomidine, an alpha-2 agonist anaesthetic agent, has antioxidant effects. In this study, the effects of dexmedetomidine on oxidative stress in CABG surgery were investigated. Methods Patients who underwent on-pump CABG surgery were divided into two groups: those receiving dexmedetomidine (Group D) and those not receiving dexmedetomidine (Group C). From anesthesia induction to the end of surgery, patients in Group D received intravenous infusions of 0.05–0.2 mcg/kg/min remifentanil and 0.2–0.7 mcg/kg/h dexmedetomidine. Patients in Group C received intravenous infusion of 0.05–0.2 mcg/kg/min remifentanil. Blood samples were collected from the patients 30 min before induction of anesthesia (T1), 30 min after removal of the aortic cross-clamp (T2), and at the end of the surgery (T3). Thiol-disulfide homeostasis (TDH) was assessed using a novel method. A novel automated method enables the determination of native thiols, total thiols and disulfides levels in plasma, allowing the calculation of their respective ratios. Results In patients receiving dexmedetomidine, lower postoperative levels of disulfide, disulfide/native thiol, and disulfide/total thiol, along with higher native thiol/total thiol, were observed compared to the control group. (p 0.05) Conclusions In our study, through dynamic thiol-disulfide measurements, we found that levels of oxidative stress (OS) were lower in patients who received dexmedetomidine. We believe that the positive effects of dexmedetomidine on OS could be beneficial in CABG surgery. Furthermore, we anticipate that with further studies conducted in larger patient cohorts, the clinical utilization of dexmedetomidine will become more widespread. Trial registration number NCT05895331 / 06.07.2023.