Evaluation of the dynamic thiol/disulfide homeostasis in patients with chronic venous insufficiency.

OBJECTIVE: There is no study in the literature evaluating the dynamic thiol/disulfide homeostasis in patients with chronic venous insufficiency. Thus, we designed this study to evaluate the dynamic thiol/disulfide homeostasis as a novel indicator of oxidative stress in patients with chronic venous insufficiency. METHODS: This was a prospective case-control study performed at the department of cardiovascular surgery of a tertiary referral hospital in Turkey. A total of 80 (CEAP C3-C6) patients with lower extremity chronic venous insufficiency (as the study group) and 80 healthy subjects (as the control group) were enrolled to the study. The participants' basic demographic and clinical characteristics as well as serum levels of some laboratory parameters including albumin, ferroxidase, myeloperoxidase, native thiol, total thiol, disulphide, native thiol/total thiol, disulphide/native thiol, and disulphide/total thiol were determined, and then compared between the groups. RESULTS: In terms of basic demographic and clinical characteristics, both groups were statistically similar, and there were no significant differences between the groups. When the laboratory parameters were considered, serum ferroxidase and myeloperoxidase levels were detected to be significantly higher, whereas albumin, native thiol, total thiol, and disulphide levels were detected to be significantly lower in the study group than in the control group. CONCLUSIONS: Dynamic thiol/disulphide homeostasis could be considered as an indicator reflecting the oxidative stress status in patients with chronic venous insufficiency.

A comprehensive assessment of redox balance in small for gestational age newborns and their mothers.

OBJECTIVE: The objective of this study was to assess oxidative stress in small for gestational age (SGA) newborns and their mothers by evaluating intra- and extracellular thiol homeostasis and the quantification of major oxidants and antioxidants. METHODS: A total of 75 mothers and their 75 newborns (43 SGA) were enrolled in this study. Thiol-disulfide homeostasis, serum myeloperoxidase, catalase, total oxidant, and antioxidant status were analyzed. Additionally, erythrocytic glutathione (GSH) homeostasis was measured. RESULTS: Although native and total thiol levels were decreased, disulfide levels were increased in SGA groups. Additionally, myeloperoxidase activity and total oxidant status levels were significantly elevated whereas total antioxidant status levels and enzymatic antioxidant systems were diminished in SGA groups. Similarly, intra-erythrocytic GSH homeostasis was shifted in favor of oxidants in SGA groups. CONCLUSION: Our results demonstrate that insufficient antioxidant systems in mothers and a robust source of oxidative stress in SGA might contribute to the pathophysiology of SGA births.

OPRD1 rs569356 polymorphism has an effect on plasma norbuprenorphine levels and dose/kg-normalized norbuprenorphine values in individuals with opioid use disorder.

This study aimed to determine the effects of nine OPRM1, OPRD1 and OPRK1 polymorphisms on plasma BUP and norbuprenorphine (norBUP) concentrations and various treatment responses in a sample of 122 patients receiving BUP/naloxone. Plasma concentrations of BUP and norBUP were detected by LC-MS/MS. PCR-RFLP method was used to genotype polymorphisms. OPRD1 rs569356 GG had significantly lower plasma norBUP concentration (p = 0.018), dose- (p = 0.049) and dose/kg-normalized norBUP values (p = 0.036) compared with AA. Craving and withdrawal symptoms were significantly higher in OPRD1 rs569356 AG+GG relative to AA. There was a statistically significant difference between the OPRD1 rs678849 genotypes in the intensity of anxiety (13.5 for CT+TT and 7.5 for TT). OPRM1 rs648893 TT (18.8 ± 10.8) was significantly different to CC+CT (14.82 ± 11.3; p = 0.049) in view of the intensity of depression. This current study provides the first data on a prominent effect of the OPRD1 rs569356 variation on BUP pharmacology due to its metabolite norBUP.

Levetiracetam treatment in an experimental model of sciatic nerve injury: A randomized controlled trial.

AIM: This study examined whether levetiracetam contributes to improvements in the axon-nerve damage in an experimental rat model. MATERIALS AND METHODS: Forty-eight Wistar albino adult male rats weighing 250-300 gr were randomized into six groups having or not having sciatic nerve damages and receiving different (none, 300 and 600 mg/kg) levetiracetam doses, and control (non-levetiracetam). Functional gait analysis and tissue sample analysis with the aid of light microscopy and hematoxylin-eosin dye were evaluated between the groups. Additionally, scanning electron microscopy (SEM) was used for the detailed examination of sciatic nerves. S-100 (Schwann cell marker) immunoreactivities in sciatic nerve was detected by immunohistochemistry. RESULTS: Sciatic functional index of the injured rats receiving 300 mg/kg levetiracetam was -65.59 ± 29.48 and -47.13 ± 21.36 in the 2nd and 6th weeks, respectively (p < 0.001). Also, IMA and TOS levels were significantly higher in the control group compared to those receiving levetiracetam (p = 0.001 and p < 0.001, respectively).      The most significant nerve regeneration was in the group injured and treated with LEV 600 mg/kg (p < 0.05). CONCLUSION: There was a significant improvement in the sciatic functional index, histopathological findings, and parameters showing tissue oxidant status in rats with sciatic nerve injury receiving levetiracetam treatment. Further investigations should be performed to evaluate the contribution of levetiracetam as a treatment modality in sciatic nerve injuries.

Sublingual buprenorphine/naloxone treatment is not affected by OPRM1 A118G and BDNF Va66Met polymorphisms, but alters the plasma beta-endorphin and BDNF levels in individuals with opioid use disorder.

The study aimed to examine the genetic contribution to buprenorphine (BUP) treatment in individuals with opioid use disorder (OUD), with a specific focus on BDNF and OPRM1 genes. A total of 113 controls and 111 OUD patients receiving sublingual BUP/naloxone were enrolled. OPRM1 A118G and BDNF Val66Met polymorphisms were investigated by PCR-FRLP. Plasma BDNF and beta-endorphin levels were assessed by ELISA kits in both groups. Blood BUP levels were measured by LC-MS/MS and normalized with daily BUP dose (BUP/D). OPRM1 A118G and BDNF Val66Met polymorphisms didn't have an effect on plasma beta-endorphin and BDNF levels in OUD patients, respectively. Interestingly, OUD patients had significantly higher plasma BDNF and lower beta-endorphin levels compared to the controls (p < 0.001). A negative and significant correlation between plasma BUP/D and BDNF levels was found. Age onset of first use was associated with OPRM1 A118G polymorphism. The findings indicated that sublingual BUP/naloxone may increase plasma BDNF levels, but may decrease beta-endorphin levels in individuals with OUD. Plasma BDNF level seemed to be decreased in a BUP/D concentration-dependent manner.

The effect of acid use as a preservative on the results of biochemical tests measured in 24-h urine.

Twenty-four-hour urine measurements play a crucial role in the diagnosis, follow-up and treatment of various diseases. There are different approaches to the collection of urine in patients who need to collect multiple urine samples at a time, especially in hospitals with heavy workloads. In this study, we compared the sodium, potassium, chloride, amylase, calcium, creatinine, phosphorus, microalbumin, protein, magnesium, urea, uric acid, adrenaline, noradrenaline, dopamine, metanephrine, normetanephrine, vanillylmandelic acid, 5-hydroxyindoleacetic acid and homovanillic acid results of 24-h urine samples analyzed immediately without acid addition, which we accepted as the reference and baseline measurement, with the results of the samples analyzed after waiting for 24 h without acid addition, analyzed immediately with acid addition and analyzed after waiting for 24 h with acid addition. Chloride, microalbumin, amylase and protein tests, which are recommended to be measured in the sample without preservatives, are affected by acid addition. Adrenaline, noradrenaline and dopamine, which are the tests recommended to be measured in acid-added urine are degraded in the samples without acid, and the levels of metanephrine and normetanephrine were not significantly degraded in the absence of preservatives.

COVID-19 patients with altered steroid hormone levels are more likely to have higher disease severity.

PURPOSE: This study aims to evaluate the correlations between the severity of the disease and serum steroid levels by analyzing the serum steroid levels in COVID-19 patients with different levels of disease progression and the control group. METHODS: Morning serum Aldosterone, 11-deoxycortisol, Androstenedione, 17-hydroxyprogesterone, Dihydrotestosterone (DHT), Dehydroepiandrosterone (DHEA), Corticosterone, Dehydroepiandrosterone sulfate (DHEAS), Estrone, Estradiol, Progesterone, 11-deoxycorticosterone, Cortisol, Corticosterone, Androsterone, Pregnenolone, 17-hydroxypregnenolone and 21-deoxycortisol levels were measured in 153 consecutive patients were grouped as mild, moderate, and severe based on the WHO COVID-19 disease severity classification and the control group. Steroid hormone levels were analyzed at once with a liquid chromatography-tandem mass spectrometric method (LC-MS/MS). RESULTS: In our study, nearly all steroids were statistically significantly higher in the patients' group than in the control group (p < 0.001). Also, DHEA was an independent indicator of the disease severity with COVID-19 CONCLUSIONS: Our study reveals that the alteration in steroid hormone levels was correlated with disease severity. Also, steroid hormone levels should be followed up during COVID-19 disease management.

Effects of UGT2B7 rs7662029 and rs7439366 polymorphisms on sublingual buprenorphine metabolism in heroin addicts: An improved PCR-RFLP assay for the detection of rs7662029 polymorphism.

This study aimed to determine the effects of UGT2B7 rs7662029 and rs7439366 polymorphisms on plasma buprenorphine (BUP) concentration and different treatment responses in a sample of 109 patients with opioid use disorder (OUD) treated with sublingual BUP/naloxone. Polymorphisms were analysed by PCR-RFLP. Plasma concentrations of BUP and its metabolite norbuprenorphine were detected by LC-MS/MS. Craving, withdrawal, depression and anxiety were measured by appropriate scales. OUD patients with rs7439366 CC or rs7662029 GG genotypes had significantly lower dose-normalized (BUP/D) and dose/kg-normalized BUP (BUP/D.kg-1) levels than those who were CT or AA carriers. Significant associations between UGT2B7 rs7662029 and increased craving (p = 0.037) and withdrawal symptoms (p = 0.029) were detected. Our findings were pointing to an important role of UGT2B7 in the metabolism of sublingual BUP/naloxone in the heroin addicts for the first time. A novel PCR-RFLP assay was developed for the determination of UGT2B7 rs7662029 polymorphism, based on utilizing novel restriction enzyme.

Can chlorogenic acid reduce oxidative stress and in an experimental spinal cord injury?

BACKGROUND: We aimed to investigate antioxidant and neuroprotective properties of chlorogenic acid in spinal cord injury (SCI). METHODS: Twenty-one rats were divided into three groups. Laminectomy was performed in group L (n=7), spinal cord trauma was induced in group T (n=7), and spinal cord trauma was induced and chlorogenic acid treatment was started in group C (n=7). Blood samples were collected to analyze baseline values and the 12th h, 1st day, 3rd day, and 5th day catalase, native thiol (NT), total thiol (TT), disulfide (SS), SS/TT, SS/NT, and NT/TT levels. Functional analysis with Basso-Beattie and Bresnahan scores was performed at the same time points. Total antioxidant status (TAS), total oxidative stress, oxidative stress index, and cyclooxygenase-2 (Cox-2) were examined in the spinal cord of rats euthanized on day 7; results were statistically analyzed. RESULTS: On day 7, catalase levels in Group C were significantly higher than baseline levels, whereas those in Group T were significantly lower than baseline levels; Group L showed no significant difference (p=0.008). SS values on day 7 were lower in Group T than in Groups C and L. Group C showed the lowest decrease in NT/TT level after trauma. On day 7, SS/TT level was high in Group T but stable in Groups C and L (p=0.04). Histopathological examination revealed significantly lower Cox-2 and TAS levels in Group C than in Group T (p=0.003, p=0.017, respectively). CONCLUSION: In this study, SCI was primarily examined through thiol-SS balance, and it was demonstrated by experimental models that chlorogenic acid has antioxidant and neuroprotective effects in SCI.

Low Anti-Mullerian Hormone Levels Are Associated with the Severity of Anxiety Experienced by Healthcare Professionals During the COVID-19 Pandemic.

The objective of this study is to investigate a possible correlation between anxiety status and anti-Mullerian hormone (AMH) levels among healthcare professionals who provide medical care directly to COVID-19-positive patients during the recent pandemic. Fifty-two healthcare professionals (nurses, midwives, and residents) who provide medical care directly to COVID-19-positive patients in inpatient clinics or intensive care units were enrolled in this study. Serum AMH levels were analyzed to reflect ovarian reserve. The Beck Anxiety Inventory (BAI) and the State-Trait Anxiety Inventory (STAI-S and STAI-T, respectively) were completed by participants to assess their anxiety status. A linear regression model with participant age as the constant variable was applied to analyze the relationship between inventory scale scores and AMH levels. P-values less than 0.05 were considered statistically significant. The mean AMH value was significantly lower for the participants in the moderate/severe anxiety group compared to the minimal/mild anxiety group (p = 0.007). A linear regression analysis revealed a significant negative correlation between AMH levels and both BAI (B = -0.030, standard error = 0.010, p = 0.004) and STAI-S and STAI-T scores when age was controlled (both p = 0.003). The severity of anxiety experienced during the recent COVID-19 pandemic among healthcare professionals, who provide medical care directly to COVID-19-positive patients, is found to be related to low AMH levels.

Evaluation of the diagnostic performance of an oral fluid screening test device for substance abuse at traffic controls.

INTRODUCTION: The aim of this study was to evaluate the analytical performance of the Kite Biotechnology Oral fluid (OF) screening test device, which is used for roadside screening of cannabis, opiates, amphetamines, methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA), cocaine and benzodiazepines by comparing samples with matched plasma samples, analysed via liquid chromatography-tandem mass spectrometry (LC-MS/MS) for confirmation. METHODS: OF and plasma samples were obtained simultaneously from a total of 100 subjects. OF samples were analysed by OF screening test based on immunochromatography. The OF screening test cut-off values were 50 ng/mL for amphetamines (d-amphetamine) and methamphetamine/MDMA (d-methamphetamine), 30 ng/mL for cocaine (benzoylecgonine), 40 ng/mL for opiates (morphine), 20 ng/mL for benzodiazepines (nordazepam), and 25 ng/mL for cannabis (Δ9-tetrahydrocannabinol). LC-MS/MS method validation was performed according to the CLSI C62-A recommendations with the following parameters: matrix effect, lower limit of quantification (LLOQ), linearity, intra-day and inter-day precision and accuracy. RESULTS: The overall specificity, accuracy and negative predictive values (NPV) were acceptable and met the DRUID standard of >80%. The OF screening test device showed good sensitivity for cocaine, amphetamines and opiates, whereas it indicated poor sensitivity for methamphetamine/MDMA (66.7%) and failed to detect cannabis and benzodiazepines. CONCLUSION: The present study is the first report to evaluate the Kite Biotechnology OF screening test device. The diagnostic performance of the OF screening test device was acceptable for opiates, cocaine and amphetamines, but it was insufficient for methamphetamine/MDMA, benzodiazepines and cannabis because of sensitivity issues.

Assessment of Diastolic Function and Thiol-Disulphide Homeostasis in Arsenic-Exposed Workers.

OBJECTIVES: Exposure to arsenic is associated with various cardiovascular diseases. The imbalance between antioxidant and oxidant homeostasis plays a crucial role in the cardiovascular effects of arsenic. The aim of this study was to investigate the effect of arsenic exposure on diastolic function by measuring thiol and disulphide in arsenic-exposed workers. METHODS AND RESULTS: A total of 107 male arsenic-exposed workers and 36 healthy subjects were enrolled. Mitral inflow velocity and parameters of diastolic function were measured. As oxidative stress indicators, total thiol, native thiol, disulphide, and their percent ratios were determined. The mean age was 39.1 ± 9.5 years in the arsenic-exposed group and 37.4 ± 9.6 years in the controls. The median blood arsenic level was 42 µg/dL in the arsenic-exposed group and 3.75 µg/dL in the controls. E-wave, E/A ratio, and e' wave were lower and left atrial diameter, A-wave, average E/e' ratio, and tricuspid regurgitation velocity were higher in the arsenic-exposed group. Native and total thiol concentrations were lower, and disulphide/native and disulphide/total thiol ratios were higher in the arsenic-exposed group. Fourteen (13.1%) workers had diastolic dysfunction, 26 (24.3%) had indeterminate, and 67 (62.6%) had normal diastolic function, compared to 1 (2.8%), 2 (5.6%), and 33 (97.7%) in the control group, respectively. In regression analysis, disulphide/native thiol ratio (p < 0.001) and blood arsenic level (p < 0.001) predicted increased average E/e' ratio in the arsenic-exposed group. CONCLUSIONS: This study showed strong associations among arsenic exposure, oxidative stress, and diastolic function, and revealed the influence of arsenic exposure on diastolic dysfunction through oxidative stress.

Anti-inflammatory and antioxidative effects of genistein in a model of spinal cord injury in rats.

Background: Neurological damage from spinal cord injury (SCI) is a result of primary mechanical injury and secondary damage from oxidative stress and neuroinflammation. Although genistein has been shown to have potent antioxidant and anti-inflammatory effects in studies of brain injury, its effect on secondary damage in SCI has remained unknown. Objective: To determine effects of genistein in a model of SCI in rats. Methods: We divided 21 rats evenly into 3 groups, a control group, in which only a laminectomy was performed; a trauma group in which SCI was induced; and a genistein group in which genistein was administered subcutaneously after SCI. The rats were assessed using a Basso-Beattie and Bresnahan functional score at the 12th hour and on the 1st, 3rd, 5th, and 7th days. Biochemical analyses were conducted at the same time points to determine the serum levels of catalase, ischemia-modified albumin (IMA), disulfide (SS), total thiol (TT), native thiol (NT), disulfide/total thiol (SS/TT), and native thiol/total thiol (NT/TT). Total oxidant and antioxidant capacity, and oxidative stress index were determined in spinal cord tissue obtained on the 7th day together with immunohistochemistry for cyclooxygenase-2 levels. Result: Catalase activity on the 7th day was significantly (P = 0.001) higher in the genistein-treated rats than in other groups, and IMA levels became stable earlier (3rd day) in the genistein group. SS values were significantly (P = 0.004) lower in the genistein group. NT/TT ratio were significantly (P = 0.049) higher in the genistein-treated rats on the 7th day. Conclusion: Genistein has antioxidant, anti-inflammatory, and protective effects in a model of SCI in rats and warrants further study.

Relationship Between Vasospasm and Serum Chromogranin A Levels in an Experimental Subarachnoid Hemorrhage Model.

AIM: To analyze Chromogranin A levels on vasospasm in an experimental subarachnoid heamorrhage (SAH) model. MATERIAL AND METHODS: Sixteen Wistar Albino male rats were used in study. Two groups are formed; first was consisting of 8 rats that experimental SAH was performed on them, second group was control group that nothing was done. Animals were sacrified fourtyeight hours later subarachnoid heamorrhage was occured. Peripheral venous blood samples were taken from the experimental group before SAH formation, 15 minutes, 75 minutes after experimental SAH formation and 48 hours as peak of vasospasm. Simultaneous peripheral venous blood samples were also collected from the control group. Blood samples were biochemically evaluated after centrifugation and serum Chromogranin A levels were studied. RESULTS: Serum chromogranin A levels increased statistically significant (p < 0.05) at the 15th minute after SAH, as the samples obtained from the experimental and control groups were anticipated as a result of the statistical analysis of the data after the biochemical examinations. CONCLUSION: In all these findings, we concluded that Chromogranin A could be used as a marker for the investigation of endocrine stress in the early period of post-SAH vasospasm and it could be proved by more studies.

Dynamic thiol/disulphide homeostasis metrics as a risk factor for peripheral arterial disease.

OBJECTIVE: To examine dynamic thiol/disulphide homeostasis metrics as a novel risk factor of oxidative stress in patients with peripheral arterial disease. METHODS: One hundred patients with lower extremity peripheral arterial disease (a study group) and 100 control subjects were included in this prospective case-control study. Participants' baseline clinical characteristics and laboratory data including some oxidant/antioxidant status parameters such as albumin, ferroxidase and myeloperoxidase, and thiol/disulphide homeostasis parameters such as native thiol, total thiol and disulphide, as well as native thiol/total thiol, disulphide/native thiol and disulphide/total thiol ratios were all recorded and then compared between the groups. RESULTS: Mean albumin and ferroxidase, and median myeloperoxidase levels were found to be significantly higher in patients with the peripheral arterial disease than in control group (p = 0.045, p = 0.000 and p = 0.000, respectively). Mean native thiol and total thiol, and median disulphide levels were found to be significantly lower in the study group as compared with the control group (p = 0.000, p = 0.000 and p = 0.037, respectively). According to the results of logistic regression analysis, systolic blood pressure, ferroxidase and myeloperoxidase levels were detected to be the independent predictors of peripheral arterial disease. CONCLUSION: Our report is the first one in the literature investigating dynamic thiol/disulphide homeostasis metrics as a novel risk factor of oxidative stress in peripheral arterial disease. Dynamic thiol/disulphide homeostasis metrics may be used as a valuable risk factor of oxidative stress in patients with the peripheral arterial disease since it is readily available, easily calculated and relatively cheap.

Trace elements and oxidative stress status in patients with psoriasis.

INTRODUCTION: Psoriasis is a common, inflammatory skin disease of which etiopathogenesis is still not explained clearly, however in which trace elements and oxidative stress are considered to play a role. AIM: To evaluate the serum trace element and oxidative stress levels in patients diagnosed with psoriasis. MATERIAL AND METHODS: A total of 87 psoriasis patients and 60 healthy subjects were included in the study. Serum sodium (Na), potassium (K), calcium (Ca), phosphorus (P), magnesium (Mg), iron (Fe), selenium (Se), zinc (Zn), copper (Cu) levels, oxidative stress parameters, ischemia-modified albumin (IMA), catalase (CAT), myeloperoxidase (MPO) and ferroxidase (FOX) activity and an inflammatory marker, C-reactive protein (CRP), were examined in all participants. RESULTS: IMA, IMA/Albumin (IMA/Alb), CAT, Cu, FOX and CRP levels were found to be significantly higher; Se, Zn and albumin levels were significantly lower in the patient group as compared to the control group. No significant difference was found between groups with regard to Na, K, Ca, P, Mg, Fe and MPO levels. CONCLUSIONS: Some trace element levels and oxidant-antioxidant balance were changed in psoriasis patients.

New Oxidative Stress Markers Useful in the Diagnosis of Acute Appendicitis in Children: Thiol/Disulfide Homeostasis and the Asymmetric Dimethylarginine Level.

OBJECTIVES: The aim of this study was to evaluate 2 new oxidative stress markers, thiol/disulfide homeostasis status and the asymmetric dimethylarginine (ADMA) level, in children with acute appendicitis (AA) and to evaluate their diagnostic utility. METHODS: This case-control study included 45 patients with AA and 35 healthy children. Age, sex, white blood cell count, neutrophil-to-lymphocyte ratio, high-sensitivity C-reactive protein (hs-CRP) level, ultrasonographic findings, thiol/disulfide homeostasis parameters (native and total thiol levels, native thiol/total thiol ratios [antioxidant parameters], and disulfide, disulfide/native thiol, and disulfide/total thiol ratios [oxidant parameters]), and the ADMA level were compared between the 2 groups. RESULTS: The native and total thiol levels, and the native thiol/total thiol ratio, were significantly lower, and the disulfide level and disulfide/native thiol and disulfide/total thiol ratios significantly higher, in the AA compared with the control group (all P < 0.001). The ADMA level was significantly higher in a perforated versus nonperforated subgroup of AA patients, but the thiol/disulfide homeostasis parameters did not differ significantly between the two subgroups. In addition, the hs-CRP level and appendiceal wall thickness were higher in the perforated subgroup. The thiol/disulfide antioxidant parameters and ADMA level correlated negatively with the white blood cell count, the neutrophil-to-lymphocyte ratio, and the hs-CRP level, in the AA group, but correlated positively with oxidant parameters. The sensitivity and specificity of the disulfide/native thiol and disulfide/total thiol ratios were high when used to diagnose AA, whereas the sensitivity of the ADMA level was high when used to diagnose perforated appendicitis. CONCLUSIONS: Thiol/disulfide homeostasis and the ADMA level, together with certain other parameters, may be useful biomarkers of AA in children.

Serum endocan level and diastolic functions in the case of lead exposure

Background/aim: Lead can cause morphological and functional changes in heart, and inflammation and endothelial dysfunction in vasculature. Endocan, as a novel indicator of endothelial dysfunction, has been used for cardiovascular diseases. This study investigated the relationship between lead exposure, endocan levels, and diastolic functions. Materials and methods: A total of 51 lead-exposed workers without a known cardiovascular disease or risk factors and 54 healthy controls were enrolled. All participants underwent transthoracic echocardiography. Blood lead and serum endocan levels were analyzed. Results: Baseline demographic and clinical characteristics were found to be similar between groups. Median blood lead (32 vs 1.5 µg/dL, P < 0.001) and serum endocan levels (67 vs 57.1 pg/mL, P = 0.02) were significantly higher in the lead-exposed group. Serum endocan level showed a positive correlation with blood lead levels (r = 0.404, P = 0.003) in lead-exposed workers. Serum endocan level was an independent risk factor for increased E/E' ratio (ß = 0.704, P = 0.002) and left atrial volume index (ß = 1.158, P = 0.011) and higher level of lead in blood was an independent risk factor for increased E wave (ß = 8.004, P = 0.022) in lead-exposed workers. Conclusion: Worsened diastolic functions may be seen in the course of lead exposure. Due to sharing a similar mechanism, a higher serum level of endocan may be a valuable laboratory clue for impaired diastolic function in this population.

Serum asymmetric dimethylarginine and nitric oxide levels in Turkish patients with acute ischemic stroke.

BACKGROUND: Nitric oxide synthase (NOS) is present in the brain and cerebral arteries and it enables the synthesis of nitric oxide (NO), which plays a critical role in brain perfusion. Asymmetrical dimethylarginine (ADMA) is an endogenous NOS inhibitor. OBJECTIVES: The aim of this study was to evaluate serum ADMA levels, which are an indicator of endothelial dysfunction of the renal functions in patients with acute ischemic stroke, and to determine whether there is a possible correlation between ADMA and NO levels and the l-arginine-to-ADMA ratio. MATERIAL AND METHODS: Fifty-two patients (22 male and 30 female; mean age: 75.2 ±10.1 years) with a diagnosis of acute ischemic stroke in the first 24 h post-stroke and 48 healthy individuals (controls; 13 male and 35 female; mean age: 60.1 ±7.92 years) were included in this study. The risk factors recorded and evaluated were age and gender of the patients, serum lipid levels, serum ADMA levels, nitrate-to-nitrite ratios, l-arginine, l-arginine-to-ADMA ratios, sedimentation rate, C-reactive protein (CRP), urea and creatinine levels, and glomerular filtration ratio (eGFR). RESULTS: The mean serum ADMA level was 0.48 ±0.23 µM for the patients and 0.36 ±0.18 µM for the controls. The mean NO level was 2.78 ±0.59 µM for the patient group and 4.49 ±2.84 µM for the controls. The ADMA levels for the patient group were significantly higher than for the control group (p = 0.011); the NO levels for the patients were significantly lower than for the controls (p < 0.001). The logistic regression method demonstrated that ADMA and NO levels may be independent risk factors for the patient group, and the receiver operating characteristic (ROC) curve analysis showed that both of these variables were discriminative risk factors. CONCLUSIONS: An increased serum level of the NOS inhibitor ADMA was found to be a possible independent risk factor for ischemic stroke.

A new potential biomarker in early diagnosis of firefighter lung function impairment: dynamic thiol/disulphide homeostasis.

OBJECTIVES: The aim of this study was to investigate the associations between urinary arsenic, oxidative stress, assessed by thiol/disulphide homeostasis, and lung diseases in firefighters. METHODS: The study conducted among the municipality-based male firefighters (n = 100) who were admitted to occupational diseases clinic for periodic medical examination. The control group consisted of non-exposed male office workers (n = 50). Urinary arsenic levels, thiol/disulphide homeostasis parameters of participants were determined. Also, lung diseases were assessed by chest X-ray and pulmonary function tests. RESULTS: The mean age and work year did not differ in the study and control group. The median urinary arsenic concentration of firefighters was significantly higher than in the control group: 15.65 (2.5-246) µg/L and 3 (0.10-6) µg/L, respectively (p < 0.001). The parameters of pulmonary function tests (PFT) FVC (%), FEV1 (%), FEV1/FVC ratio and FEF 25-75 (%) were all significantly lower in firefighters compared to controls. A significant increase in mean serum disulphide concentration (17.10 ± 8.31 µmol/L vs. 7.48 ± 5.91) (Fig. 1) and disulphide/native thiol % ratio: 3.63 (0.53-11.43) vs. 1.51 (0.03-7.65) (p < 0.001) were found between exposed group and controls. The Spearman's correlation analysis revealed a positive correlation between urinary arsenic and disulphide (r = 0.422, p < 0.001), disulphide/native thiol % ratio (r = 0.409, p < 0.001). Nevertheless, urinary arsenic correlated negatively with all PFT parameters including FVC (%), FEV1 (%), FEV1/FVC and FEF 25-75 (%) (p < 0.001). CONCLUSION: We showed the arsenic-induced oxidative stress in firefighters with impairments of several lung functions determined by thiol/disulphide homeostasis using a novel method.