Total oxidant status and oxidative stress are increased in infants with necrotizing enterocolitis

Background

Oxidative stress has been implicated in the pathogenesis of necrotizing enterocolitis (NEC). In this study, we compared the global oxidant/antioxidant status by measuring total antioxidant capacity (TAC), total oxidant status (TOS), and oxidative stress index (OSI) in preterm infants with NEC and with control preterms.

Methods

Forty-one preterm neonates with NEC (stage 1 [group 1; n = 23] and stages 2 and 3 [group 2; n = 18]) and age-matched 36 healthy preterm controls (group 3) were included in this study. Blood samples were obtained both at the time of NEC diagnosis and 72 hours after for the evaluation of TAC and TOS. Serum levels of TAC, TOS, and OSI in patients with NEC were compared with controls.

Results

Demographic characteristics were comparable in all 3 groups. Preterm neonates in group 2 (with stages 2 and 3 NEC) had the highest TOS levels and OSI (P < .001 vs both groups 1 and 3). There was no difference in TAC levels among the groups (P = .26).

Conclusions

Our findings demonstrated that although TAC levels were similar in all 3 groups, oxidant stress mechanisms were activated in preterm neonates with definite NEC (stages 2 and 3 NEC). Premature neonates with increased levels of TOS and OSI were associated with severity of NEC.     

Evaluation of serum oxidative and antioxidative status in patients with erectile dysfunction

We evaluated and compared serum oxidative and antioxidative parameters of patients with erectile dysfunction (ED) and control subjects. Twenty married male patients with ED for at least 12 months (Group 1) and 20 volunteer healthy, sexually active, married and age-matched men (Group 2) were included in the study. Group 1 and 2 were compared concerning serum mean total antioxidant capacity (TAC), total oxidant status (TOS), paraoxonase1 (PON1), arylesterase, total thiol and oxidative stress index (OSI). Mean patient age was 47.9 ± 8.1 and 44.4 ± 10.6, respectively, in Group 1 and 2. Serum TAC levels were 1.7 ± 0.5 and 2.3 ± 0.3, respectively, in Group 1 and 2 (P = 0.002). Serum TOS levels were 21.8 ± 20.5 and 11.7 ± 2.2, respectively, in Group 1 and 2 (P = 0.035). Serum PON1 levels were 69.8 ± 13.1 and 164.9 ± 56.5, respectively, in Group 1 and 2 (P < 0.001). Serum arylesterase levels were 336 ± 12 and 370.4 ± 47.9, respectively, in Group 1 and 2 (P = 0.003). Serum total thiol levels were 733.1 ± 253 and 885.5 ± 95.3, respectively, in Group 1 and 2 (P = 0.016). Serum OSI was 0.14 ± 0.17 and 0.05 ± 0.11, respectively, in Group 1 and 2 (P = 0.021). Mean blood platelet count was significantly higher in Group 1 (P = 0.001). A positive correlation between platelets and oxidative state and a negative correlation between platelets and antioxidative state were found. Oxidative stress was detected to be increased, whereas antioxidative parameters were detected to be decreased in patients with ED.     

Blood and semen paraoxonase—arylesterase activities in normozoospermic and azoospermic men

Paraoxonase and arylesterase enzymes are corner stones of antioxidant defence. We aimed to compare azoospermic infertile men and normozoospermic individuals with respect to total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), paraoxonase and arylesterase levels in the blood and seminal plasma. Two‐hundred consecutive infertility patients and voluntarily participated were included. In the normozoospermic group, TAS, PON, arylesterase values were statistically significantly higher when compared with those in the azoospermic group, while lower TOS and OSI levels were observed in the blood and seminal plasma of azoospermic group. In the semen analyses of normozoospermic group, the correlation between semen volume, sperm concentration, sperm motility and morphology and TAS, TOS, OSI, PON and arylesterase values was examined. A negative correlation was determined between semen volume and OSI. Levels of serum oxidative parameters were higher in the azoospermic group relative to normozoospermic group, but antioxidant parameters were lower than those of the normozoospermic group. Oxidative stress performs an essential role in the aetiology of male infertility by negatively influencing sperm quality and function. Assessment of blood and seminal plasma oxidative profiles might be an important tool to better evaluation of sperm reproductive capacity and functional competence.     

Relationship between oxidative stress parameters and asymptomatic organ damage in hypertensive patients without diabetes mellitus

Abstract

Objective. We aimed to evaluate the levels of oxidative stress (OS) parameters such as total antioxidant status or TAS, total oxidant status (TOS), OS index (OSI), paraoxonase 1 (PON1), arylesterase, and total thiol in hypertensive patients with and without asymptomatic organ damage (AOD), and to determine the relationship between these parameters and AOD. Design. Sixty-six patients (21 men, 45 women) with AOD and 66 patients without AOD (21 men, 45 women) were enrolled in the study. Serum OS parameters were measured by colorimetric method. Results. The OSI levels were found to be higher while PON1, PON1/high-density lipoprotein, and arylesterase levels were found to be lower in patients with AOD compared with those in the patients without AOD. Stepwise regression analysis showed high 24-h mean systolic blood pressure, OSI, and low arylesterase level to be independent predictors of AOD. Conclusion. OS level was found to be higher in hypertensive patients with AOD compared with the patients without AOD. However, it is not clear whether increased OS leads to AOD or AOD increases the level of OS. For this purpose, OS level needs to be decreased by antioxidant therapies and patients need to be followed up for a longer duration.     

Paraoxonase-1 activity in subfertile men and relationship to sperm parameters

Oxidative stress has been implicated in the pathogenesis of male infertility. Paraoxonase-1 (PON-1) is a high-density lipoprotein-associated antioxidant enzyme that prevents oxidative modification of low-density lipoprotein. Our aims in the study were to investigate 1) seminal PON-1 activity in subfertile men and 2) whether seminal PON-1 activity had any relationship to semen parameters. The study included 28 men with idiopathic subfertility, 32 subfertile men with abnormal semen parameters, and 30 fertile male volunteers. Seminal PON-1 activity was measured spectrophotometrically. Seminal total antioxidant status (TAS) and total oxidant status (TOS) were determined by using colorimetric methods. Oxidative stress index (OSI) was calculated as ([TOS/TAS] x 100). TOS and OSI were significantly higher and PON-1 activity and TAS were significantly lower in subfertile men with abnormal semen parameters than in men with idiopathic subfertility and fertile donors. PON-1 activity was also strongly correlated with sperm concentration (r = .68, P < .0001), motility (r = .58, P < .0001), and morphology (r = .62, P < .0001) in the overall group. The receiver operating characteristic curve analysis revealed a high diagnostic value for PON-1 activity with respect to male-factor subfertility, with an area under curve of .95 (95% confidence interval = 0.89-1.01), sensitivity = 97%, and specificity = 88%. Men with abnormal semen parameters have decreased levels of PON-1 activity in their seminal plasma. This may play an important role in the pathogenesis of male-factor subfertility.     

Ways in which SWL affects oxidant/antioxidant balance

Many damages can occur in the kidneys following extracorporeal shock wave lithotripsy (SWL) and some of these damages are thought to emerge as a result of oxidative stress. The objective of this study is to evaluate the impact of SWL application on kidneys in stone patients on oxidative stress parameters in 24-h urine. The study included 20 patients scheduled for SWL. total antioxidant capacity (TAC) and total oxidant status (TOS) measurements were made on 24-h urines of the patients before and after SWL. The oxidative stress index (OSI) was calculated based on these values. Following SWL, while TOS increased in 24-h urine (p = 0.006), TAC remained unchanged (p = 0.312). OSI increased following the procedure (p = 0.004). SWL application disrupts the oxidant/antioxidant balance in favor of oxidants, which leads to oxidative stress. TOS, TAC and OSI may be useful in the determination of the existence of oxidative stress following SWL.     

The influence of hemodialysis membrane permeability on serum paraoxonase-1 activity and oxidative status parameters

We aimed to measure oxidative stress parameters and paraoxonase-1 (PON-1) enzyme activities in chronic hemodialysis (HD) patients and to investigate whether HD membrane permeability has any influence on those measures. Forty-seven HD patients and 24 controls were enrolled. At the first step of the study, all HD patients had undergone HD treatment via "low-flux" membranes for 4 weeks. At the second step of the study, the membranes were switched to "high-flux" membranes and HD treatments were also performed via "high-flux" membranes for 4 weeks. Blood samples were withdrawn after completion of 4 weeks treatment for each membrane. Total oxidant status (TOS), total antioxidant status (TAS), and paraoxonase and arylesterase activities were measured in blood samples of the patients and the controls. TOS and oxidative stress index (OSI) of both membranes were higher than controls (all, P < 0.05), while TAS and paraoxonase and arylesterase activities were lower (all P < 0.05). Paraoxonase (P < 0.05, r = -0.437 and P < 0.05, r = -0.453, respectively) and arylesterase (P < 0.05, r = -0.333 and P < 0.05, r = -0.371, respectively) activities of "low-flux" and "high-flux" membranes were inversely correlated with OSI. There were no significant differences between "low-flux" and "high-flux" membranes in regard to oxidative stress parameters or PON-1 enzyme activities (all, P > 0.05). HD patients have increased oxidative stress and decreased serum PON-1 activities inversely correlated with oxidative stress. Membrane permeability seems to have no influence on oxidative stress parameters and PON-1 enzyme activities.     

Protective effect of syringic acid on kidney ischemia-reperfusion injury

The objective of the present study was to determine whether preischemic administration of syringic acid (SA) would attenuate renal ischemia-reperfusion injury (IRI). Rats were divided into three groups: Sham group; IR group; and IR?+?SA group. The effects of SA were examined using biochemical parameters including serum ischemia-modified albumin (IMA), total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), tissue superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) and malondialdehyde (MDA). The apoptosis status and histopathological changes were evaluated. After calculating the score for each histopathological change, the total score was obtained by summing all the scores. In the SA group, MDA, IMA, TOS, and OSI decreased significantly compared to the IR group. After SA administration, the increase in GPx activity was found to be significant. Apoptosis decreased significantly in the SA group compared with the IR group. The total score significantly decreased after administration of SA. Taken together, our findings suggest that SA preconditioning is effective in reducing tissue damage induced in kidney IRI. Renal histology also showed convincing evidence regarding the protective nature of SA.     

The Relationship Between Leptin Level and Oxidative Status Parameters in Hemodialysis Patients

Both serum leptin level and oxidative stress are increased in hemodialysis (HD) patients. In the present study, we aimed to investigate whether there is association between oxidative status and leptin level in HD patients. Thirty-five HD patients and 25 healthy controls were enrolled in the present study. Serum leptin level, total peroxide (TP) level, total antioxidant capacity (TAC), and oxidative stress index (OSI) were determined. Serum leptin level, TP level, and OSI were significantly higher in HD patients than controls (all P  < 0.001) while TAC was lower ( P  < 0.001). In HD patients, serum leptin level was significantly correlated with TP level and OSI ( r  = 0.372, P  <  0.001 and r  = 0.409, P  < 0.001, respectively). The correlation of serum leptin level with TP level and OSI remained statistically significant after adjusting for age, gender, and body-fat percentage ( r  = 0.446, P  < 0.001 and r  = 0.463, P  < 0.001, respectively). Hyperleptinemia seems to be associated with increased oxidative stress in HD patients, and this association may provide better understanding about the disorders related to either elevated serum leptin levels and/or increased oxidative stress in HD patients.     

Measurement of oxidant and antioxidant levels in liver tissue obtained from patients with liver transplantation: A case-control study

ObjectiveThis study aimed to compare oxidant and antioxidant substance accumulation in the liver tissues of patients with chronic liver disease (recipients) who underwent liver transplantation (LT) with living liver donors (LLDs) who underwent living donor hepatectomy (LDH).MethodsThis prospective study included 160 recipients (LT group) and 40 LLDs (LLD group). During surgery, a piece of liver tissue measuring a minimum of 10 × 10 mm was obtained from the edge of the right lobe of the liver of recipients and LLDs, incubated for 10 min in saline to remove blood, and stored at −70 °C until biochemical analysis was performed. Catalase (CAT), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), myeloperoxidase (MPO), prolidase, reduced glutathione (GSH), malondialdehyde (MDA), total oxidant status (TOS), total antioxidant status (TAS), oxidative stress index (OSI), total thiol, native thiol, and disulfide levels were measured in stored liver tissues.ResultsThere was a statistically significant difference between LT and LLD groups in terms of age (p < 0.001), body mass index (p = 0.019), GSH-Px (p < 0.001), SOD (p = 0.001), MPO (p < 0.001), prolidase (p < 0.001), GSH (p < 0.001), and MDA (p = 0.003) values in favor of the LT group. Furthermore, there was a statistically significant difference between LT and LLD groups in terms of CAT (p < 0.001), TAS (p < 0.001), TOS (p < 0.001), OSI (p < 0.001), total thiol (p < 0.001), native thiol (p < 0.001), and disulfide (p < 0.001) values in favor of the LLD group. There were no differences between the groups in terms of sex.ConclusionThis study demonstrated that it is possible to assess the extent of oxidative stress in liver tissues by measuring the levels of antioxidant enzymes, oxidants, or the end-products of oxidative stress. With the use of optimum and minimally invasive methods, quantifying these molecules will potentially help evaluate the extent of liver disease and prognostication of liver cirrhosis.     

The short term effects of resveratrol on ischemia–reperfusion injury in rat testis

Purpose

The purpose of this study was to identify changes taking place in the rat testis at the 24th hour of reperfusion following testicular torsion and to evaluate the effects of resveratrol (RSV), a powerful antioxidant, in preventing these changes using novel biochemical parameters and histopathology.

Methods

Eighteen adult male rats were divided into three groups: Sham-operated (S), torsion/detorsion (T/D), and T/D + RSV groups. In the T/D group, testicular ischemia was achieved by rotating the left testis 720° clockwise for 4 h. In the T/D + RSV group, 20 mg/kg RSV was administered intraperitoneally 30 min before detorsion. All rats were sacrificed 24 h after detorsion. Serum and tissue malondialdehyde (MDA) concentrations, ischemia modified albumin (IMA), total oxidative status (TOS), total antioxidant status (TAS), oxidative stress index (OSI), and histopathological damage score were analyzed.

Results

Serum MDA, IMA, TOS, and OSI levels rose significantly in the T/D group. Serum MDA and IMA values were lower in the T/D + RES groups, but not significantly. OSI and TOS values were lower in the T/D + RES group, and the difference was significant. TAS values decreased significantly in the T/D group and rose in the T/D + RSV group, but not significantly. Ipsilateral tissue MDA values were significantly elevated in the T/D group and decreased in the T/D + RSV group, but not significantly. Apoptosis and histopathological damage increased significantly in the T/D group and decreased significantly in the T/D + RSV group. In the contralateral testis, apoptosis increased significantly in the T/D group. It decreased significantly in the T/D + RSV group.

Conclusions

Our findings show that RSV had a protective effect against oxidative damage induced with a testicular T/D model, especially at the antiapoptotic and histopathological level. OSI may be a good guide to the clinical status of testicular T/D.     

Anti-apoptotic and anti-oxidant effects of grape seed proanthocyanidin extract in preventing cyclosporine A-induced nephropathy

Aim: Although the pathogenesis of cyclosporine (CsA) nephropathy is not completely understood, it is attributed to oxidative damage and apoptosis. Grape seed proanthocyanidin extract (GSPE) is a molecule with anti‐oxidant and anti‐apoptotic properties. Our aim was to demonstrate the effects of GSPE in preventing CsA nephropathy. Methods: Twenty‐four Sprague–Dawley rats were divided into four groups. The control, GSPE, CsA and CsA+GSPE groups were given 1 mL olive oil, 100 mg/kg GSPE, 25 mg/kg CsA and 100 mg/kg GSPE+25 mg/kg CsA, respectively. On day 21, blood samples were taken for blood urea nitrogen (BUN), creatinine and CsA levels, and renal tissue was used for total oxidant system (TOS), total anti‐oxidant system (TAS), oxidative stress index (OSI) and malondialdehyde (MDA) measurements. In addition to renal histopathology, apoptosis staining was performed on renal tissue. Results: The BUN, creatinine, TOS, OSI, MDA, histopathological score, and apoptotic index exhibited increases in the CsA group. In the CsA+GSPE group, however, BUN, creatinine, OSI, MDA, renal histopathological score and apoptotic index (AI) decreased and TAS levels increased. In addition, there was no difference between the CsA and CsA+GSPE groups with regard to CsA levels. Conclusion: We demonstrated that GSPE prevents CsA nephropathy and that this effect is achieved by anti‐apoptotic and anti‐oxidant activity. We also achieved a significant recovery in kidney functions without affecting CsA plasma levels.     

Beneficial effects of aminoguanidine on radiotherapy‐induced kidney and testis injury

This experimental study was designed to investigate both protective and therapeutic effects of aminoguanidine (AG), on radiotherapy (RT)‐induced oxidative stress in kidney and testis. Forty rats were divided into five groups equally as follows: (i) control, (ii) RT, (iii) AG, (iv) AG+RT and (v) RT+AG group. Histopathological findings and biochemical evaluations, including tissue malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathione (GSH), total oxidant status (TOS), total antioxidant capacity, oxidative stress index (OSI), blood urea nitrogen (BUN), serum creatinine (Cr) and testosterone levels, were determined. MDA, TOS and OSI were significantly higher in RT‐treated groups, whereas SOD, CAT, GPX and GSH were significantly lower in these groups when compared with the control rats in the kidney and testis tissue. AG treatment significantly decreased MDA, TOS and OSI levels and increased SOD, CAT, GPX and GSH levels, when compared to the RT‐treated groups in both kidney and testis tissue. BUN and Cr levels did not change among the groups, whereas testosterone levels were found as reduced in the RT‐treated rats. AG treatment significantly augmented these hazardous effects of RT on testis tissue. According to our results, AG has beneficial effects against RT‐induced kidney and testis injury.     

Total antioxidant and oxidant status of plasma and renal tissue of cisplatin-induced nephrotoxic rats: protection by floral extracts of Calendula officinalis Linn.

The present study was aimed to determine the total antioxidant status (TAS), total oxidant status (TOS) and oxidative stress index (OSI) of plasma and renal tissue in cisplatin (cDDP) induced nephrotoxic rats and its protection by treatments with floral extracts of Calendula officinalis Linn. Treatment with cDDP elevated (p?p?C. officinalis along with cDDP restored (p?>?0.05) CR, albumin, TOS, GSH and activities of antioxidant enzymes in blood and renal tissue. Ethanolic extract treatments reduced (p?C. officinalis protect cDDP induced nephrotoxicity by restoring antioxidant system of the renal tissue.     

Endocrine status and markers of collagen synthesis and degradation in serum and urogenital tissue from women with and without stress urinary incontinence

AIMS: To investigate possible differences in androgen/estrogen status between patients with stress urinary incontinence (SUI) and healthy women's and to study possible associations between circulating estrogens and androgens on the one hand and collagen synthesis and metabolism in urogenital tissue on the other. METHODS: Markers of collagen turnover, the carboxy-terminal propeptide of type I procollagen (PICP), the carboxy-terminal telopeptide of type I collagen (ICTP), and the amino-terminal propeptide of procollagen III (PIIINP), were assayed in urogenital tissue homogenates and estradiol-17beta (E2), total testosterone (T), and sex-hormone-binding globulin (SHBG) were assayed in peripheral serum from 58 patients with SUI and 30 urologically healthy women. Apparent concentrations of free testosterone (fT) were calculated from T, SHBG, and a fixed albumin value. RESULTS: Significant positive correlations were found between E2 and PICP in controls and between E2 and ICTP in SUI patients without exogenous hormones. Significant negative and sometimes strong correlations were found between serum T and fT on the one hand and all three collagen turnover markers on the other. These correlations were strengthened when parity and/or body mass index (BMI) were reduced. No correlations between T and fT and collagen turnover markers were found in the controls. There were no significant differences between any of the groups in serum E2, T, or fT. CONCLUSION: Estrogens may increase collagen turnover in urogenital tissue, however, the clinical significance of this is still unclear. Androgens may affect urogenital tissue negatively by slowing down collagen turnover, probably by inhibition of matrix metalloprotease (MMP) synthesis and/or activity. Urogenital tissue in SUI patients and in urologically healthy women may differ in androgen sensitivity.     

Serum indoleamine 2,3 dioxygenase and tryptophan and kynurenine ratio using the UPLC-MS/MS method,in patients undergoing peritoneal dialysis,hemodialysis, and kidney transplantation

Background: The level and activity of indoleamine 2,3-dioxygenase (IDO) and the concentrations of L-tryptophan and its metabolite L-kynurenine were determined in association with various renal diseases. However, there have been no data regarding these parameters in patients on peritoneal dialysis compared to those undergoing hemodialysis or kidney transplantation.

Methods: This study investigated the level and activity of IDO and determined oxidative balance by calculating the total oxidant status (TOS), total antioxidant status (TAS), and oxidative stress index (OSI). We enrolled 60 kidney disease patients, including 20 on peritoneal dialysis (PD group), 19 on hemodialysis (HD group), and 21 with kidney transplantation (KT group), as well as 21 control group.

Results: IDO levels were increased in the PD, HD, and KT groups compared to the control group. The concentration of kynurenine was significantly increased in the PD group compared to the other groups (p?p?p?Conclusion: The results showed that IDO levels were increased in peritoneal dialysis and hemodialysis patients and in renal transplant recipients, while oxidative stress was found to be related to IDO activity and was most increased in the patients on peritoneal dialysis.     

Association of interleukin 18-607A/C and -137C/G polymorphisms with oxidative stress in renal transplant recipients

Objectives IL-18 mediates various inflammatory and oxidative responses including renal injury, fibrosis, and graft rejection. It has been reported that the promoter -607 and -137 polymorphisms of IL-18 influence the level of IL-18. This prospective observational study investigated the association between oxidative stress with IL-18-607 and -137 polymorphisms in renal transplant recipients. Patients and methods This study included 75 renal transplant recipients (28 female, 47 male) from living-related donors. Blood samples were collected immediately before and after transplantation at day 7 and month 1. Serum IL-18, creatinine, cystatin C, CRP, and oxidative stress markers (TOS, TAC) were measured. The Oxidative Stress Index (OSI) was calculated. Polymorphisms of the promoter region of the IL-18 gene, IL18-607A/C, and -137C/G were determined by analysis of a “real-time PCR/Melting curve”. Results Serum creatinine, cystatin C, CRP, IL-18, TOS, and OSI levels significantly decreased after transplantation. Post-transplant levels of serum TAC and estimated GFR demonstrated consistent significant increases. Serum IL-18 levels were significantly higher in patients with IL-18-137 GG and IL-18-607?CC genotypes before transplantation. Conclusion Our results indicate that the IL-18-137 GG and -607?CC genotypes contribute to higher IL-18 levels; however, the influence of these polymorphisms on oxidative stress has not been observed.     

Markers of collagen synthesis and degradation in urogenital tissue from women with and without stress urinary incontinence

AIMS: Multiparity and obesity are risk factors for stress urinary incontinence (SUI), but collagen synthesis and metabolism in the urogenital tissue itself may also affect its function and control of micturition. Whether changes in synthesis or degradation of collagen are part of the etiology of SUI is not known and published studies show diverging results. The aims of the present study was to investigate collagen turnover in urogenital tissue in women with SUI (n=71) and in urologically healthy women (n=31). METHODS: Markers of collagen synthesis and breakdown, the carboxy-terminal propeptide of type I procollagen (PICP), the carboxy-terminal telopeptide of type I collagen (ICTP), and the amino-terminal propeptide of procollagen III (PIIINP) were assayed in urogenital tissue homogenates and peripheral serum. RESULTS: In the total clinical material SUI patients were significantly older, had a significantly higher body mass index (BMI) and significantly lower serum PICP and tissue ICTP levels than the controls. When healthy controls were compared with SUI patients matched for age, BMI, parity, and hormonal/menopausal status (31 women in each group), the SUI patients had significantly lower serum concentrations of PICP and significantly lower tissue concentrations of PIIINP and ICTP than the controls. Within the total material of SUI patients, post-menopausal women with weak and strong HRT and pre-menopausal women had significantly lower S-ICTP concentrations than untreated post-menopausal patients. Significant negative correlations to parity were found for T-PIIINP and T-PICP and to BMI for T-ICTP. CONCLUSIONS: The low tissue collagen marker levels in women with SUI suggest a reduced collagen turnover, which may negatively affect tissue strength and elasticity.     

Is oxidative stress related to childhood urolithiasis?

Background

Urolithiasis is a common condition in pediatric populations in Turkey. The role of oxidative stress in renal stone formation in pediatric patients has not been reported to date. The aim of this study was to assess oxidative stress in childhood urolithiasis.

Methods

Seventy-four children diagnosed with urolithiasis and 72 healthy control subjects were enrolled in the study. Kidney stone formers were evaluated by analysis of metabolic conditions related to urolithiasis, such as hypercalciuria, hyperoxaluria, hypocitraturia and hyperuricosuria. Urine total antioxidant status (TAS), and total oxidant status (TOS) were measured, and oxidative stress index (OSI) was calculated as an indicator of the degree of oxidative stress.

Results

Among the stone formers, metabolic analyses revealed that 30 % had hypercalciuria, 45 % had hypocitraturia, 6 % had hyperoxaluria and 40 % had hyperuricosuria. Elevated levels of the renal tubular damage marker urinary N-acetyl- beta-d-glucosaminidase (NAG) was elevated in 25 % of the patient group, but microalbuminuria was not detected. Total oxidant status and total antioxidant status were significantly higher in stone formers than in the controls (p?=?0.023 and 0.004, respectively). In addition, urinary NAG was significantly correlated with TOS (r?=?0.427, p?=?0.019).

Conclusions

The results of this study show that oxidative stress may play an important role in the pathogenesis of pediatric stone formers.     

Changes in collagen metabolites in serum after cemented hip and knee arthroplasty

Summary Markers of types I and III collagen turnover were measured in serial blood samples collected preoperatively and 60 days after surgery in 13 patients undergoing cemented total hip arthroplasty and 11 patients undergoing cemented total knee arthroplasty. The markers were the carboxyterminal extension peptide of type I procollagen (PICP) and the aminoterminal extension peptide of type III procollagen (PIIINP). The course of serum PICP and serum PIIINP in the two treatment groups were uniform. Serum PICP showed an initial fall on day 4, thereafter increasing up to days 14–28 and was still elevated on day 60. Serum PIIINP was increased on day 4, reaching its maximum on days 14–21, and thereafter declined but remained elevated above initial values. Serum osteocalcin, a serological marker of osteoblast activity, showed no significant changes in the two treatment groups during the observational period. We suggest that the changes in serum PICP and serum PIIINP reflect collagen formation in healing soft connective tissue 60 days after cemented hip or knee arthroplasty.