The associations between serum paraoxonase 1 activity and carotid atherosclerosis in renal transplant patients.

BACKGROUNDS AND AIMS: Paraoxonase 1 (PON1) is a novel marker that has been shown to exert protective functions on atherosclerosis by preventing oxidative modification of serum lipoproteins. In this study, we investigated the effects of PON1 on CA-IMT in renal transplant patients. METHODS: A total of 98 adult renal transplant recipients was enrolled in the study. CA-IMT was determined by B-mode Doppler ultrasonography. PON-1 activity was assessed by the rate of enzymatic hydrolysis of paraoxon to p-nitrophenol. RESULTS: Mean age was 39.4 ± 9.6 years and 10% of the patients were diabetic. Time after transplant was 76 ± 59 months. Mean PON1 level was 62.1 ± 43.3 U/l. PON1 levels were negatively correlated with CA-IMT and positively with HDL cholesterol. Mean CA-IMT was 0.62 ± 0.10 mm (0.40 - 0.98). CA-IMT was positively correlated with age, male gender and negatively with proteinuria and PON1 levels. In linear regression analysis, PON1 levels were associated with CA-IMT. CONCLUSION: Reduced PON1 activity is significantly associated with increased carotid atherosclerosis in renal transplant patients.

High prevalence of cardiovascular risk factors in a Western urban Turkish population: a community-based study.

OBJECTIVE: Cardiovascular diseases (CVD) are the largest cause of morbidity and mortality in Turkey and in the World. Heart of Balçova Project is a community- based health promotion project that aims to reduce CVD incidence and prevalence through risk factor modification in the individual and population level. This paper presents results of the baseline survey that aimed to define CVD risk factors and risk of developing coronary heart disease (CHD) in the Balçova population. METHODS: The study population included 36,187 people over 30 years of age residing in Balçova in 2007. Individuals were interviewed at their homes. Anthropometrics and blood pressure were measured and in total 12914 fasting blood samples were collected for lipid and glucose analyses. CHD risk was estimated using Framingham risk equation. Student's t test, Chi-square for trend test and ANOVA were used to compare mean levels and percentages of risk factors between age groups and gender. RESULTS: In total 5552 men and 10528 women participated in the study. Smoking prevalence was 38.6% in men and 26.8% in women. The prevalence of obesity was 29.4% among men and 44.2% among women and obesity prevalence increased until the age group 75 years old. While 14.6% of men and 12.6% of women had diabetes, 39.8% of men and 41.8% of women had hypertension. The prevalence of high total cholesterol was 56.0% in men and 50.6% in women. Men had a higher risk of developing CHD compared to women in the following 10 years (13.4% vs 2.5%). CONCLUSION: The prevalence of preventable risk factors for CHD is very high in Balçova population. Community-based interventions should be planned and implemented targeting both the high-risk individuals and whole population.

Serum paraoxonase 1 activity predicts arterial stiffness in renal transplant recipients.

AIM: Paraoxanase 1 (PON 1) has been shown to protect against atherosclerosis by modifying lipoproteins. Its activity decreases in dialysis patients but is restored after transplantation. Whether it affects arterial stiffness is unclear. In this study we aimed to investigate the effects of PON 1 on arterial stiffness in renal transplant patients. METHODS: Seventy renal transplant recipients were enrolled. Arterial stiffness was measured using a Syphmocor device. PON-1 activity was assessed from the rate of enzymatic hydrolysis of paraoxon to p-nitrophenol. RESULTS: Mean age was 39.0 ± 9.6 years and 5.7% of the patients were diabetic. Post-transplant follow-up time was 46.7 ± 37.9 months. Eighty-five percent received anti-hypertensive and 12.9% anti-hyperlipidemic medication. Mean PON1 activity was 75.9 ± 52.4 U/L. PON1 activity was negatively correlated with systolic and diastolic blood pressure, mean arterial pressure, LDL-cholesterol and carotid-femoral pulse wave velocity (cf-PWV). Mean c-f PWV was 8.10 ± 1.39 m/s. Cf-PWV was positively correlated with age, systolic and diastolic blood pressure, mean arterial pressure, proteinuria and negatively correlated with PON1, PON1/HDL ratio and creatinine clearance. In linear regression analysis, PON1 was a predictor of cf-PWV in a model that included age, gender, diabetes, mean arterial pressure, urine protein level, creatinine clearance and PON 1. CONCLUSIONS: Reduced PON1 activity is significantly associated with increased arterial stiffness. The results of this study show the possible role of PON1 for arterial stiffening in renal transplant recipients.

Effect of levothyroxine replacement therapy on paraoxonase-1 and carotid intima-media thickness in subclinical hypothyroidism.

BACKGROUND: Paraoxonase-1 (PON-1) may play an important role in atherosclerosis. Atherosclerosis is an inflammatory disease and C-reactive protein is a marker for inflammation. The aim of this study was to determine serum PON-1 activity and high-sensitivity C-reactive protein (hs-CRP) levels and assess carotid intima-media thickness, a marker of early atherosclerotic changes, in patients with subclinical hypothyroidism. MATERIAL/METHODS: hs-CRP concentrations and PON-1 activity with respect to carotid intima-media thickness were evaluated in 38 subclinical hypothyroidism patients (normolipidemic, mean age: 49.79+/-10.04 years) before and after 3 months of stable euthyroidism and compared with those of 19 euthyroid normolipidemic healthy individuals (mean age: 49.95+/-8.12 years). RESULTS: At baseline, the patients with subclinical hypothyroidism had similar levels of PON-1 activity and hs-CRP and a similar lipid profile as the controls; however, the carotid intima-media thickness was greater than in the controls. Levothyroxine treatment had no effect on serum PON-1 activity and hs-CRP level, but it resulted in a significant reduction in carotid intima-media thickness in the subclinical hypothyroidism patients. CONCLUSIONS: PON-1 activity and hs-CRP levels did not significantly differ between subclinical hypothyroid patients and controls. Although levothyroxine treatment might have the potential to reverse the progression of atherosclerosis in subclinical hypothyroid patients, PON-1 activity and hs-CRP levels were not affected by this treatment. The reduction in carotid intima-media thickness was independent of the decrease in serum lipid profile or other variables.

The protective effects of carnosine and melatonin in ischemia-reperfusion injury in the rat liver.

The reperfusion following liver ischemia results in hepatocyte damage and apoptosis. The aim of this study was to investigate the effects of two antioxidant agents, carnosine and melatonin, in rat liver ischemia-reperfusion injury. Five study groups were formed; I. sham, II. ischemia-reperfusion, III. ischemia-reperfusion+melatonin, IV. ischemia-reperfusion+carnosine, V. ischemia-reperfusion+melatonin+carnosine. Then 250 mg/kg carnosine and 10 mg/kg melatonin were administered intraperitoneally 30 min before ischemia and immediately after the reperfusion. Sinusoidal dilatation, congestion and neutrophil infiltration were observed in the ischemia-reperfusion group while these symptoms were less pronounced in the treatment groups. Alanine aminotransferase, aspartate aminotransferase and myeloperoxidase levels were increased in the ischemia-reperfusion group while they were lowered in the treatment groups. Glutathione level was low in the ischemia-reperfusion group while it tended to increase in the ischemia-reperfusion+carnosine administered and ischemia-reperfusion+carnosine+melatonin administered groups. There was an increase in the number of apoptotic cells in the ischemia-reperfusion group while this number was lowered in the treatment groups. Carnosine was more effective than melatonin in the reversal of structural and biochemical alterations that resulted from ischemia-reperfusion injury. The administration of melatonin and carnosine together yielded better outcomes compared to the sole administration of each agent.

The comparative effects of total hepatic vascular isolation techniques performed at different durations in rat.

BACKGROUND: Total hepatic vascular exclusion (THVE) leads to massive venous congestion below the level of diaphragm and may promote undesirable hemodynamic disturbances in some patients. Supraceliac aortic clamping during THVE may achieve hemodynamic stability at the price of arterial ischemia. However, the parenchymal injury of venous congestion has been a greater concern than of arterial ischemia in various settings. We hypothesized that supraceliac aortic occlusion during THVE may attenuate the reperfusion injury and improve the outcome that would be acquired after THVE alone. MATERIAL AND METHODS: Rats were randomly assigned to (1) THVE alone, (2) THVE plus aortic occlusion, (3) THVE plus celio-mesenteric arterial occlusion or (4) sham during 30, 45, or 60 min followed by 180 min reperfusion period. Serum enzymes (alanine aminotransferase, lactate dehydrogenase) and creatinine as well as tissue "thiobarbituric acid reactive substances" (TBARS) and histopathology were evaluated. Seven animals per group were followed for survival up to 7 d. RESULTS: After 30 min, no difference was found in serum enzyme, creatinine and tissue TBARS measures among the isolation methods used. In these, all rats survived to 7 d. However, after 45 and 60 min isolation, aortic occlusion resulted in significant rise in serum enzyme and tissue TBARS measures as well as poor survival (14% and 0%, respectively). In contrast, all rats survived even after 60 min of THVE. CONCLUSIONS: THVE was tolerated up to 60 min with less reperfusion injury and better survival than celio-mesenteric arterial occlusion and supraceliac aortic occlusion in the rat, if needed, aortic clamping should not exceed 30 min. Beyond that, selective celio-mesenteric arterial occlusion may be considered.

Comparison and evaluation of two C-reactive protein assays based on particle-enhanced immunoturbidimetry.

The use of C-reactive protein (CRP) assays is increasing for a wide range of clinical conditions, and consequently the analytical performance requirements for CRP assays are also changing. For this reason, manufacturers have been developing CRP assays based on different methodologies to provide both high sensitivity and a wide measuring range. However, it is questionable whether these methods can meet the desired requirements for CRP assays. CRP Latex on the Cobas Integra 400 and CRP Tina-quant Latex on the Modular Analytics-P were evaluated in terms of detection limit, linearity, intra- and interassay precision, and comparability with 268 patient samples. The intra- and interassay precision of the two methods was <4.1% in the three pools with CRP concentrations ranging from 6.9 to 215 mg/L, and >10% in the pool with concentrations of approximately 0.60 mg/L. The detection limits for CRP Latex and Tina-quant Latex were 0.20 and 0.22 mg/L, respectively. Both methods were linear up to 215 mg/L. There was a good agreement between the two assays, except for a scattering at concentrations near the detection limits. Deming regression analysis for CRP Latex (x-axis) and Tina-quant Latex (y-axis) yielded a slope of 1.067+/-0.018, an intercept of -0.148+/-0.358, and an S(y/x) of 5.10 (r=0.996, P<0.0001). The two assays gave comparable results. Low precision was determined for both assays, except for the low pool with a concentration of approximately 0.60 mg/L. We concluded that both of these assays should be improved to meet high-sensitivity criteria.

[The diagnostic validity of screening tests and laboratory markers in alcohol use disorders]. / Alkol Kullanim Bozukluklarinda Tarama Testleri ve Laboratuvar Belirteçlerinin Tanisal Etkinligi.

OBJECTIVE: To determine the validity of screening tests and markers suggested in the early detection of alcohol use disorders. METHOD: Male patients aged 20-65 were recruited from a psychiatry clinic. They had been consuming alcohol at least once a week. They were not drug users and had no other diseases that affected the markers mentioned in this study. According to the DSM-IV diagnostic criteria, the diagnostic validity of screening tests [Michigan Alcoholism Screening Test (MAST), CAGE (Cut down, Annoyed, Guilty, Eye-opener), Alcohol Use Disorders Identification Test (AUDIT)] and markers [Mean corpuscular volume (MCV), aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase (GGT), carbohydrate-deficient transferrin (CDT)] was investigated in alcohol dependent patients (n=29), alcohol abusers (n=28) and social drinkers (n=28). RESULTS: For the diagnosis of dependence, the sensitivity and specificity of the tests were respectively 69% and 100% for GGT, 41% and 93% for CDT, 100% and 57% for MAST, 97% and 86% for CAGE, and 100% and 75% for AUDIT. For the diagnosis of abuse, the sensitivity and specificity of the tests were respectively 32% and 100% for GGT, 32% and 93% for CDT, 86% and 57% for MAST, 75% and 85.7% for CAGE, and 89% and 75% for AUDIT. The widest area under the ROC curve belonged to GGT as a marker and AUDIT as a screening test. CONCLUSION: According to the results of this study, the marker that has the highest validity is GGT, while AUDIT and CAGE are the best screening tests.