Incidence of cancer and overall risk of mortality in individuals treated with raltegravir-based and non-raltegravir-based combination antiretroviral therapy regimens

Objectives

There are currently few data on the long‐term risk of cancer and death in individuals taking raltegravir (RAL). The aim of this analysis was to evaluate whether there is evidence for an association.

Methods

The EuroSIDA cohort was divided into three groups: those starting RAL‐based combination antiretroviral therapy (cART) on or after 21 December 2007 (RAL); a historical cohort (HIST) of individuals adding a new antiretroviral (ARV) drug (not RAL) to their cART between 1 January 2005 and 20 December 2007, and a concurrent cohort (CONC) of individuals adding a new ARV drug (not RAL) to their cART on or after 21 December 2007. Baseline characteristics were compared using logistic regression. The incidences of newly diagnosed malignancies and death were compared using Poisson regression.

Results

The RAL cohort included 1470 individuals [with 4058 person‐years of follow‐up (PYFU)] compared with 3787 (4472 PYFU) and 4467 (10 691 PYFU) in the HIST and CONC cohorts, respectively. The prevalence of non‐AIDS‐related malignancies prior to baseline tended to be higher in the RAL cohort vs. the HIST cohort [adjusted odds ratio (aOR) 1.31; 95% confidence interval (CI) 0.95–1.80] and vs. the CONC cohort (aOR 1.89; 95% CI 1.37–2.61). In intention‐to‐treat (ITT) analysis (events: RAL, 50; HIST, 45; CONC, 127), the incidence of all new malignancies was 1.11 (95% CI 0.84–1.46) per 100 PYFU in the RAL cohort vs. 1.20 (95% CI 0.90–1.61) and 0.83 (95% CI 0.70–0.99) in the HIST and CONC cohorts, respectively. After adjustment, there was no evidence for a difference in the risk of malignancies [adjusted rate ratio (RR) 0.73; 95% CI 0.47–1.14 for RALvs. HIST; RR 0.95; 95% CI 0.65–1.39 for RALvs. CONC] or mortality (adjusted RR 0.87; 95% CI 0.53–1.43 for RALvs. HIST; RR 1.14; 95% CI 0.76–1.72 for RALvs. CONC).

Conclusions

We found no evidence for an oncogenic risk or poorer survival associated with using RAL compared with control groups.

Comparative study of systemic inflammatory responses in psoriasis vulgaris and mild to moderate allergic contact dermatitis

BACKGROUND

Psoriasis vulgaris (PV) is associated with low-grade systemic inflammation.

OBJECTIVE

Cytokines' and growth factors' serum patterns in patients with PV, allergic contact dermatitis (ACD) and healthy subjects were investigated to describe and compare systemic inflammatory responses in these diseases.

METHODS

A total of 12 inflammation-sensitive biomarkers were analyzed simultaneously by means of the Evidence Investigator™ biochip technology.

RESULTS

In PV, proinflammatory tumor necrosis factor (TNF)-α, interferon (IFN)-γ, interleukins (IL)-1β, -2, -6, -8, and monocyte chemoattractant protein (MCP)-1 were elevated. In ACD, 2 markers, TNF-α and MCP-1, were increased, and regulatory cytokine IL-10 was decreased. Proinflammatory IL-2 had the strongest correlations with other pro- as well as anti-inflammatory cytokines in PV and ACD, whilst IL-6 correlated positively with the Psoriasis Area and Severity Index. Growth factors' levels correlated with MCP-1, but only in PV.

CONCLUSION

Although psoriasis induces a more variegated proinflammatory systemic response, ACD is likewise associated with a systemic increase in inflammatory mediators.

Relation of exploratory behaviour to plasma corticosterone and Wfs1 gene expression in Wistar rats

Male Wistar rats exhibit significant variations in exploratory behaviour in the elevated plus-maze (EPM) model of anxiety. We have now investigated the relation between exploratory behaviour and levels of corticosterone and systemic oxidative stress. Also, the expression levels of endocannabinoid-related and wolframin (Wfs1) genes were measured in the forebrain structures. The rats were divided into high, intermediate and low exploratory activity groups. Exposure to EPM significantly elevated the serum levels of corticosterone in all rats, but especially in the high exploratory group. Oxidative stress indices and expression of endocannabinoid-related genes were not significantly affected by exposure to EPM. Wfs1 mRNA level was highly dependent on exploratory behaviour of animals. In low exploratory activity rats, Wfs1 gene expression was reduced in the temporal lobe, whereas in high exploratory activity group it was reduced in the mesolimbic area and hippocampus. Altogether, present study indicates that in high exploratory activity rats, the activation of brain areas related to novelty seeking is apparent, whereas in low exploratory activity group the brain structures linked to anxiety are activated.

Clear differences in adiponectin level and glutathione redox status revealed in obese and normal-weight patients with psoriasis

BACKGROUND

Several studies have shown increased prevalence of obesity in patients with psoriasis.

OBJECTIVES

To characterize both inflammatory- and oxidative stress-related differences between obese patients with psoriasis (OPP) and normal-weight patients with psoriasis (NWPP).

METHODS

The plasma concentrations of adiponectin and interleukin (IL)-6 were analysed by quantitative sandwich enzyme immunoassay technique in 10 patients with a body mass index (BMI)<25 and 12 patients with a BMI>30. Total glutathione and oxidized glutathione levels were measured spectrophotometrically.

RESULTS

Plasma concentration of adiponectin in NWPP was more than twice the level in healthy normal-weight controls (P<0.001), while such an elevation did not occur in OPP. OPP were characterized by a significantly increased IL-6 level, which correlated negatively with the adiponectin level (r=-0.85, P<0.001). The glutathione redox status, which was also inversely correlated with the adiponectin level (r=-0.63, P<0.05), was associated with significantly increased oxidative stress in the OPP compared with the NWPP or controls.

CONCLUSIONS

Obesity in patients with psoriasis is associated with both decreased plasma levels of protective adiponectin compared with NWPP, and enhanced systemic inflammation and oxidative stress. These findings are in concordance with high prevalence of diseases related to lower adiponectin levels among psoriasis patients.

Homocysteine status in former top-level male athletes: possible effect of physical activity and physical fitness

The importance of elevated homocysteine (Hcy) as a risk marker for cardiovascular disease is continuously under debate. Lifestyle factors may increase the total Hcy (tHcy) level of the plasma, but there are no consistent findings relating to Hcy, physical activity, and cardiorespiratory fitness. Cross-sectional measurement from an ongoing follow-up study was performed on 77 former male athletes and 33 sedentary controls (age range 35-62 years). Lifestyle parameters (current physical activity patterns, smoking, etc.), anthropometric and blood pressure data, and data about tHcy, reduced, and oxidized glutathione (GSH, GSSG, respectively) in blood, lipoproteins, and maximal oxygen consumption (VO(2max)) were collected. Our study results showed that the subgroup of physically active ex-athletes (n=52) had a significantly lower tHcy level and glutathione redox ratio (GSSG:GSH) in comparison with the subgroup of sedentary ex-athletes (n=25). tHcy level was inversely related to cardiorespiratory fitness (VO(2max)/kg). Dietary and smoking habits were not significantly associated with the tHcy level in our study group. In conclusion, the research findings indicate that both current physical activity and cardiorespiratory fitness are significantly inversely associated with an elevated homocysteine level in middle-aged former athletes.

17beta-Oestradiol stimulation of G-proteins in aged and Alzheimer's human brain: comparison with phytoestrogens

The neuroprotective action of oestrogens and oestrogen-like compounds is in the focus of basic and clinical research. Although such action has been shown to be associated with neuronal plasma membranes, the implication of G-proteins remains to be elucidated. This study revealed that micromolar concentrations (microM) of 17beta-oestradiol and phytoestrogens, genistein and daidzein, significantly (P < 0.05) stimulate G-proteins ([(35)S]GTP gamma S binding) in the post-mortem hippocampal membranes of age-matched control women with the respective maximum effects of 28, 20 and 15% at 10 microM. In the frontocortical membranes, the stimulation of G-proteins did not differ significantly from that in hippocampal membranes. Although in the hippocampus and frontal cortex of the Alzheimer's disease (AD) women's brain, 10 microM 17beta-oestradiol produced significantly (P < 0.05) lower stimulation of G-proteins than in the control regions, stimulation by phytoestrogens revealed no remarkable decline. 17beta-Oestradiol, genistein and daidzein revealed a selective effect on various G-proteins (G(alphas), G(alpha o), G(alpha i1) or G(alpha 11) plus G(beta 1 gamma 2)) expressed in Sf9 cells. At a concentration of 10 microM, 17beta-oestradiol suppressed the H(2)O(2) and homocysteine stimulated G-proteins in the frontocortical membranes of control women to a greater extent than phytoestrogens. In AD, the suppressing effect of each compound was lower than in the controls. In the cell-free systems, micromolar concentrations of phytoestrogens scavenged OH(*) and the 2.2-diphenyl-1-picrylhydrazyl free radical (DPPH(*)) more than 17beta-oestradiol did. In the frontocortical membranes of control women, the 20 microM 17beta-oestradiol stimulated adenylate cyclase with 20% maximal effect, whereas, in AD, the effect was insignificant. Genistein did not stimulate enzyme either in control or AD frontocortical membranes. Our data confirm that the agents stimulate G-proteins in control and AD women's brains, although 17beta-oestradiol and phytoestrogens have similarities and differences in this respect. We suggest that, besides the ER-dependent one, the ER-independent antioxidant mechanism is responsible for the oestrogen stimulation of G-proteins in the brain membranes. Both of these mechanisms could be involved in the neuroprotective signalling of oestrogens that contributes to their preventive/therapeutic action against postmenopausal neurological disorders.

Pre-treatment with hyperoxia before coronary artery bypass grafting - effects on myocardial injury and inflammatory response

BACKGROUND

In experimental studies, exposure to hyperoxia for a limited time before ischaemia induces a low-grade systemic oxidative stress and evokes an (ischaemic) preconditioning-like effect of the myocardium. We hypothesised that hyperoxia before cardioplegia could protect the myocardium against necrosis and stunning caused by ischaemia-reperfusion.

METHODS

Forty patients undergoing coronary artery bypass grafting were randomly exposed to an oxygen fraction of 0.4 or > 0.96 in inspired air on an average of 120 min before cardioplegia. Blood for troponin I, creatine kinase-MB, lactate, glutathione and interleukin-6 was sampled from arterial and coronary sinus cannulae during 20 min of reperfusion. Additional arterial samples were drawn 60 min after declamping and in the first post-operative morning. The cardiac index and right and left ventricular stroke work indices were measured before sternotomy and up to 12 h post-operatively.

RESULTS

Troponin I, creatine kinase-MB and lactate did not differ between the groups. Hyperoxic pre-treatment had no impact on the post-operative haemodynamic indices measured with the thermodilution pulmonary artery catheter. More oxidised glutathione was released in the hyperoxia group in the first minute of reperfusion (P = 0.015). Hyperoxic pre-treatment abolished the myocardial release of interleukin-6 during 20 min of reperfusion (P = 0.021 vs. controls). In the first post-operative morning, interleukin-6 was higher in the hyperoxia group [127.0 (86.0-140.0) vs. 85.2 pg/ml (66.6-94.5 pg/ml); P = 0.016].

CONCLUSIONS

Exposure to >96% oxygen before cardioplegia did not attenuate ischaemia-reperfusion injury of the heart in patients undergoing coronary artery bypass grafting. The only potentially beneficial effect observed was the decreased transmyocardial release of interleukin-6.

Arterial elasticity is associated with endothelial vasodilatory function and asymmetric dimethylarginine level in healthy subjects

Arterial stiffening may be linked to the reduced bioactivity of nitric oxide (NO) and increased plasma concentrations of the endogenous NO synthase inhibitor asymmetric dimethylarginine (ADMA). The aim of this study was to investigate whether large (C1) and small artery (C2) elasticity is associated with endothelial function index (EFI) and plasma concentration of ADMA. We included 63 healthy subjects, aged 19 to 70 years, in the study. EFI, C1 and C2 were assessed by pulse wave analysis (PWA) and ADMA level was measured using an enzyme-linked immunoassay. Linear regression analysis revealed significant positive correlation between EFI and both C1 and C2 (R = 0.29, p = 0.02; R = 0.38, p = 0.002, respectively). A significant inverse association occurred between ADMA and C1 as well as C2 (R = -0.32, p = 0.03; R = -0.37, p = 0.009, respectively). In multiple regression analysis, C2 was determined by EFI, ADMA, age and BMI, and C1 was correlated with EFI, age and BMI. These findings suggest that endothelial vasodilatory dysfunction and accumulation of ADMA may be important mechanisms underlying reduced arterial elasticity in healthy subjects.

Atherogenic inflammatory and oxidative stress markers in relation to overweight values in male former athletes

OBJECTIVE

To evaluate inflammation- and oxidative stress-related (OxS) background in former athletes in relation to overweight and abdominal obesity status.

DESIGN

Cross-sectional data from ongoing follow-up study.

SUBJECTS

A total of 60 middle-aged former athletes (46.6+/-7.5 years; 181.1+/-7.2 cm; 88.1 +/- 12.9 kg) and 54 age-matched controls (48.1+/-7.3 years; 181.4 +/- 6.2 cm; 89.7 +/- 14.4 kg).

MEASUREMENTS

Anthropometric characteristics, serum lipoproteins (CHOL, HDL-C, LDL-C, TG), oxidized LDL (oxLDL), diene conjugates (DC) and high-sensitive C-reactive protein (hsCRP). Information about the physical activity and other lifestyle variables were collected by the questionnaire.

RESULTS

Ex-athletes were characterized by significantly higher physical activity characteristics and lower CHOL and oxLDL in comparison with controls. Correlation analysis among ex-athletes revealed negative associations between all measured overweight data (body mass index, fat percentage, waist to hip circumferences and waist circumference (WC)), and current physical activity. Current physical activity was significantly related to OxS and inflammatory characteristics (oxLDL, DC and hsCRP) among the ex-athletes, but not among the control group. The most expressed positive correlations were found between WC, hsCRP, triglycerides (TG), DC and oxLDL in both study groups.

CONCLUSION

Our study results suggest that there exists an independent (adjusted for potential confounders) association between overweight, abdominal obesity, and atherogenic inflammatory and oxidative stress markers in ex-athletes as well as in age-matched controls. Major findings of our study show that WC is the best correlate of hsCRP, oxLDL, DC and TG levels.

Are Specific Antiretrovirals associated with an Increased Risk of Discontinuation due to Toxicities or Patient/Physician Choice in patients with Hepatitis C Virus Coinfection?

Background

Liver damage associated with hepatitis C (HCV) may influence the likelihood of experiencing discontinuation due to toxicities or patient/physician choice (TOXPC) in patients taking combination antiretroviral therapy (cART). Little information to address this concern is available from clinical trials as patients with HCV are often excluded.

Aims

To compare incidence rates of discontinuation due to TOXPC associated with specific antiretrovial drugs in patients with or without HCV.

Patients/methods

A total of 4929 patients from EuroSIDA under follow-up from January 1999 on a specific nucleoside pair (zidovudine/lamivudine, didanosine/stavudine, stavudine/lamivudine, or other) with a third drug (abacavir, nelfinavir, indinavir, nevirapine, efavirenz, lopinavir/ ritonavir or other boosted-protease inhibitor (PI)-containing regimen) and with known HCV serostatus were studied for the incidence of discontinuation of any nucleoside pair or third drug due to TOXPC. Incidence rate ratios were derived from Poisson regression models.

Results

In total 1358 patients had HCV (27.5%). During 12 799 person-years of follow-up there were 2141 discontinuations due to TOXPC for nucleoside pairs and 2501 for third drugs. The incidence of discontinuation due to TOXPC was consistently higher in patients with HCV after stratification by nucleoside pair or third drug. After adjustment for CD4+ count, gender, exposure group, time on HAART, region and treatment regimen, there were few differences in the rate of discontinuation due to TOXPC in those with HCV compared with those without for any nucleoside pairs or third drugs. Similar results were seen when concentrating on discontinuation due to toxicities alone.

Conclusions

Although patients with HCV generally had higher rates of discontinuation due to TOXPC compared with patients without HCV, there was little evidence to suggest that this was associated with any specific nucleoside pair or third drug used as part of cART. Our results do not suggest that any specific component of cART is more poorly tolerated in patients with HCV or that the presence of HCV should influence the choice between antiretrovirals used as part of a cART regimen.

Thymidine Analogue Mutation Profiles: Factors Associated with Acquiring Specific Profiles and their Impact on the Virological Response to Therapy

Background

Studies have suggested that HIV-1 may develop thymidine analogue mutations (TAMs) by one of two distinct pathways – the TAM1 pathway (including mutations 41L, 210W and 215Y) or the TAM2 pathway (including mutations 67N, 70R and 219E/Q) – under the pressure of a not fully suppressive thymidine-analogue-containing regimen.

Methods

Frozen plasma samples stored in the EuroSIDA repository were selected and sent to two central laboratories for genotypic analysis. We considered 733 patients with at least one genotypic test showing ≥1 TAMs (the first of these tests in chronological order was used). TAM1 and TAM2 genotypic profiles were defined in accordance with previous literature. Statistical modelling involved logistic regression and linear regression analysis for censored data.

Results

The observed frequencies of patterns classifiable as TAM1 or TAM2 profiles were markedly higher than the probabilities of falling into these classifications by chance alone. The chance of detecting a TAM2 profile increased by 25% per additional year of exposure to zidovudine. We found that mutations 67N and 184V were not associated with a particular TAM profile. In the presence of TAM2 profiles, the adjusted mean difference in the 6-month viral reduction was 0.96 log10 copies/ml (95% confidence interval: 0.20; 1.73) higher in patients who started stavudine-containing regimens instead of zidovudine-containing regimens.

Conclusions

This study provides evidence that the suggested TAM clustering is a real phenomenon and that it may be driven by which thymidine analogue the patients has used. In patients with TAM2-resistant viruses, stavudine appears to retain greater viral activity than zidovudine.

Hepatitis B and HIV: prevalence, AIDS progression, response to highly active antiretroviral therapy and increased mortality in the EuroSIDA cohort

BACKGROUND

Whether hepatitis B (HBV) coinfection affects outcome in HIV-1-infected patients remains unclear.

OBJECTIVE

To assess the prevalence of HBV (assessed as HBsAg) coinfection and its possible impact on progression to AIDS, all-cause deaths, liver-related deaths and response to highly active antiretroviral therapy (HAART) in the EuroSIDA cohort.

METHODS

Data on 9802 patients in 72 European HIV centres were analysed. Incidence rates of AIDS, global mortality and liver-related mortality, time to 25% CD4 cell count increase and time to viral load < 400 copies/ml after starting HAART were calculated and compared between HBsAg-positive and HBsAg-negative patients.

RESULTS

HBsAg was found in 498 (8.7%) patients. The incidence of new AIDS diagnosis was similar in HBsAg-positive and HBsAg-negative patients (3.3 and 3.4/100 person-years, respectively) even after adjustment for potential confounders: the incidence rate ratio (IRR) was 0.94 [95% confidence interval (CI), 0.74-1.19; P = 0.61]. The incidences of all-cause and liver-related mortalities were significantly higher in HBsAg-positive subjects (3.7 and 0.7/100 person-years, respectively) compared with HBsAg-negative subjects (2.6 and 0.2/100 person-years, respectively). The adjusted IRR values were 1.53 for global (95% CI, 1.23-1.90; P = 0.0001) and 3.58 for liver-related (95% CI, 2.09-6.16; P < 0.0001) mortality. HBsAg status did not influence viral or immunological responses among the 1679 patients starting HAART.

CONCLUSIONS

The prevalence of HBV coinfection was 9% in the EuroSIDA cohort. Chronic HBV infection significantly increased liver-related mortality in HIV-1-infected patients but did not impact on progression to AIDS or on viral and immunological responses to HAART.

High-sensitive C-reactive protein level and oxidative stress-related status in former athletes in relation to traditional cardiovascular risk factors

OBJECTIVE

To analyze systemic and cellular oxidative stress-related indices as well as C-reactive protein level in former top-level athletes in relation to traditional cardiovascular risk factors.

METHODS

A cross-sectional study was performed in 53 former male athletes and 25 sedentary controls (age range: 39-59 years). We measured anthropometric factors (BMI, fat percentage, WHR), resting blood pressure (SBP, DBP), serum cholesterol (CHOL), high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C), triglycerides (TG), total antioxidant status (TAS), oxidized LDL-C (oxLDL), diene conjugates (DC), glutathione redox status, high-sensitive C-reactive protein (hsCRP), and leisure-time physical activity.

RESULTS

Physically active former athletes had significantly lower mean overweight (BMI, fat percentage, WHR), better spectrum of atherogenesis indicators (CHOL, HDL-C, TG, TG:HDL-C ratio) and lower oxidative stress (oxLDL, oxLDL:LDL-C ratio, DC) values than sedentary ex-athletes. No significant differences in these variables were found between the sedentary ex-athletes and control group. Significant associations were found between physical activity (METs), SBP, DBP, hypertension, CHOL, HDL-C, TG, TG:HDL-C ratio, oxLDL, oxLDL:LDL-C ratio, DC and hsCRP.

CONCLUSIONS

A physically active lifestyle is related to a lower cardiovascular disease (CVD) risk profile including a substantially lower systemic and cellular oxidative stress status as well as C-reactive protein level in middle-aged men.

Baseline Resistance and Virological Outcome in Patients with Virological Failure who Start a Regimen Containing Abacavir: Eurosida Study

Objectives

To investigate the ability of several HIV-1 drug-resistance interpretation systems, as well as the number of pre-specified combinations of abacavir-related mutations, to predict virological response to abacavir-containing regimens in antiretroviral therapy-experienced, abacavir-naive patients starting an abacavir-containing regimen in the EuroSIDA cohort.

Patients and methods

A total of 100 HIV-infected patients with viral load (VL) >500 copies/ml who had a plasma sample available at the time of starting abacavir (baseline) were included. Resistance to abacavir was interpreted by using eight different commonly used systems that consisted of rules-based algorithms or tables of mutations. Correlation between baseline abacavir-resistance mutations and month 6 virological response was performed on this population using a multivariable linear regression model accounting for censored data.

Results

The baseline VL was 4.36 log10 RNA copies/ml [interquartile range (IQR): 3.65–4.99 log10 RNA copies/ml] and the median CD4 cell count was 210 cells/μl (IQR: 67–305 cells/μl). Our patients were pre-exposed to a median of seven antiretrovirals (2–12) before starting abacavir therapy. The median (range) number of abacavir mutations (according to the International AIDS Society-USA) detected at baseline was 3.5 (0–8). Overall, the Kaplan–Meier estimate of the median month 6 VL decline was 0.86 log10 RNA copies/ml [95% confidence intervals (95% CI): 0.45–1.24]. The VL in those patients ( n=31) who intensified treatment by adding only abacavir decreased by a median 0.20 log10 RNA copies/ml (95% CI: -0.18; +0.94). The proportion of patients who harboured viruses fully resistant to abacavir among the eight genotypic resistance interpretation algorithms ranged from 12% [Agence Nationale de Recherches sur le SIDA (ANRS)] to 79% [Stanford HIV RT and PR Sequence Database (HIVdb)]. Some interpretation systems showed statistically significant associations between the predicted resistance status and the virological response while others showed no consistent association. The number of active drugs in the regimen was associated with greater virological suppression (additional month 6 VL reduction per additional sensitive drug=0.51, 95% CI: 0.15–0.88, P=0.006); baseline VL was also weakly associated (additional month 6 VL reduction per log10 higher=0.30, 95% CI: -0.02; +0.62, P=0.06). In contrast, the number of drugs previously received was associated with diminished viral reduction (additional month 6 VL reduction per additional drug=-0.14, 95% CI: -0.28; 0.00, P=0.05).

Conclusions

Our results revealed a high degree of variability among several genotypic resistance interpretation algorithms currently in use for abacavir. Therefore, the interpretation of genotypic resistance for predicting response to regimens containing abacavir remains a major challenge.

Is elective abdominal aortic aneurysm repair accompanied by high grade oxidative stress?

BACKGROUND AND AIMS

During elective abdominal aortic aneurysm repair (AAAR), lower torso ischaemia-reperfusion event is unavoidable. Previous studies on AAAR have reported the importance of oxidative stress (OS) in ischaemia-reperfusion injury, however, the grade of OS has not been adequately clarified up to now. The aim of this study was to perform a complex investigation of the time-course and grade of systemic and cellular OS in patients undergoing AAAR.

MATERIAL AND METHODS

Arterial blood samples were taken from 18 patients undergoing elective AAAR (at four points in time: before anaesthesia, 5 min after aortic clamping and 5 min and 30 min after clamp removal). Diene conjugates (DC), thiobarbituric acid reactive substances (TBARS), total antioxidative capacity (TAC), glutathione redox ratio (GSSG/GSH), and levels of antioxidative enzymes as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSHPx) were measured from the radial arterial blood.

RESULTS

30 min after the removal of the aortic cross-clamp, arterial CAT showed significant elevation (96.0 vs 56.9 U/l, p < 0.05); GSHPx was significantly elevated (51.5 vs 39.9 U/g Hgb, p < 0.05) and TAC was decreased (31.4 vs 36.5%, p < 0.05) in comparison with preoperative value.

CONCLUSIONS

We found limited alterations of several OS parameters, which do not characterize either systemic or cellular high-grade OS during elective AAAR.

The Swedish APP670/671 Alzheimer's disease mutation: the first evidence for strikingly increased oxidative injury in the temporal inferior cortex

To evaluate the level of oxidative stress (OS) in familial Alzheimer's disease (FAD), we analysed four cerebrocortical areas from patients with Swedish FAD bearing the APP670/671 mutation. The temporal inferior cortex (TIC) from Swedish FAD patients revealed a striking 2- to 3-fold increase in diene conjugates, lipid peroxides and protein carbonyls, compared to sporadic Alzheimer's disease (AD). Compared with TIC from sporadic AD patients, the mutation carriers showed a markedly decreased activity of catalase (CAT) in the same area, and the same trend was found for another antioxidant enzyme, superoxide dismutase. These results are consistent with the deep oxidative injury of TIC in Swedish FAD. In the frontal inferior cortex (FIC), sensory postcentral cortex (SPCC) and occipital primary cortex (OPC) from Swedish FAD, the parameters of oxidative injury tended to be higher than in sporadic AD. Only the increase in the levels of lipid hydroperoxides in SPCC and of protein carbonyls in OPC was significant. Compared to sporadic AD, Swedish FAD showed a significant increase in GSSG levels and the GSSG/2GSH ratio in the FIC, SPCC and OPC. A significantly decreased activity of CAT was detectable for the SPCC and OPC in Swedish FAD. Increased OS might play a crucial role in the rapid progression of Swedish FAD from the associative temporal cortex to the primary cerebrocortical areas.

Oxidative stress markers in pre-uremic patients

AIM

The present study was designed to investigate a complex of oxidative stress (OS) markers in patients with chronic renal failure (CRF) and to study the relationship between different OS markers and degree of renal failure. The following indices of OS were measured in plasma: oxidized glutathione (GSSG), reduced glutathione (GSH), total glutathione (TGSH), glutathione redox ratio (GSSG/GSH) and resistance of lipoprotein fraction to oxidation (lag phase of LPF). Baseline diene conjugation level of lipoprotein fraction (BDC-LPF), total antioxidative activity (TAA), diene conjugates (DC), lipid hydroperoxides (LOOH) and thiobarbituric acid-reactive substances (TBARS) were measured in serum. All markers in plasma and serum were measured both in patients with CRF and in healthy controls.

SUBJECTS AND METHODS

Blood samples were obtained from 38 patients with CRF and from 61 healthy controls. Routine biochemical analyses were performed by using commercially available kits.

RESULTS

Levels of DC, BDC-LPF, LOOH, GSSG and GSSG/GSH ratio were significantly increased and lag phase of LPF was significantly shortened in patients with CRF compared with healthy controls. Serum creatinine and urea levels correlated significantly with GSSG level and GSSG/GSH in patients with CRF. A significant inverse correlation was found between glutathione redox ratio and lag phase of LPF and between GSSG level and BDC-LPF.

CONCLUSIONS

The findings suggest that renal patients are in a state of oxidative stress compared with healthy controls. The most informative indices to evaluate the degree of OS in CRF were: GSSG level, GSSG/GSH status, lag phase of LPF and BDC-LPF.

The cerebrocortical areas in normal brain aging and in Alzheimer's disease: noticeable differences in the lipid peroxidation level and in antioxidant defense

The markers of oxidative stress were measured in four cerebrocortical regions of Alzheimer's disease (AD) and age-matched control brains. In controls the levels of diene conjugates (DC) and lipid peroxides (LOOH) were significantly higher in the sensory postcentral and occipital primary cortex than in the temporal inferior or frontal inferior cortex. The antioxidant capacity (AOC) was highest in the temporal, and GSH in the frontal inferior cortex. The highest activity of superoxide dismutase (SOD) and catalase (CAT) was found in the occipital primary cortex. Compared with controls, significantly higher level of DC and LOOH and attenuated AOC were evident in AD temporal inferior cortex. In AD frontal inferior cortex moderate increase in LOOH was associated with positive correlation between SOD activity and counts of senile plaques. Our data suggest that in AD cerebral cortex, the oxidative stress is expressed in the reducing sequence: temporal inferior cortex > frontal inferior cortex > sensory postcentral cortex approximately = occipital primary cortex, corresponding to the histopathological spreading of AD from the associative to primary cortical areas.

Acute immune response in respect to exercise-induced oxidative stress

The relationship between exhaustive exercise, oxidative stress, the protective capacity of the antioxidant defense system and cellular immune response has been determined. Exhaustive exercise in well-trained young men (n=19)-induced leukocytosis, decreased proportion of activated-lymphocyte subsets (CD4+ and CD8+) expressing CD69, decreased lymphocyte mitogenic response to concanavalin A (ConA) and phytohemagglutinin (PHA), increased lipid peroxidation, increased total antioxidant status (TAS) and catalase activity, immediately after exercise. Suppressed blood concentration of T-lymphocyte subsets (CD3+, CD4+, CD8+, NK), increased TAS and blood total glutathione (TGSH) in early recovery period (30 min after exercise) were found. Strong positive correlation was observed between TGSH and lymphocyte mitogenic response to ConA and PHA (r=0.85 and 0.85, respectively) immediately after exercise. Moderate positive correlation was observed between TAS and lymphocyte mitogenic response to PHA (r=0.59) immediately after exercise as well as between TAS and lymphocyte mitogenic response to PHA and ConA (r=0.69 and 0.54, respectively). Moderate to weak correlation was observed between TAS and conjugated dienes with exercise (r=0.66) as well as in 30-min recovery (r=0.50). After a short-term bout of exhaustive exercise, immune system was characterized by acute phase response, which was accompanied with oxidative stress. Suppression of the cellular immunity 30 min after exercise shows that this period is not enough for recovery after exhaustive exercise. The results suggest the interactions between exercise-induced oxidative stress and immune response.

Epidemiology of HIV in Estonia

The aim of this study was to report on the epidemiology of HIV infection in Estonia and to molecularly characterize Estonian HIV-1 variants. Epidemiological data were obtained from the Estonian National HIV/AIDS Database. In 1995-1996 blood samples were collected from 54 of the 65 HIV-infected individuals that had been diagnosed at that time. The V3 domain of the env gene was directly sequenced from peripheral blood mononuclear cells of 49 of these 54 individuals and the sequences used for phylogenetic analyses. At the end of 1999 Estonia reported 96 diagnosed HIV cases; 46 (48%) were homosexual or bisexual men and 31 (32%) were presumed to have been infected heterosexually. Importantly, only four individuals were likely to have become infected through intravenous drug use. Forty-three individuals (45%) were presumed to have been infected outside of Estonia, whereas 38 (40%) were likely to have become infected in Estonia. As expected, a majority of the investigated individuals (80%) were found to carry subtype B virus. Infections with subtypes A, C, D, G, and CRF02_AG were also documented. The dominance of subtype B was restricted to homosexual and bisexual men. Thus, subtype B infections were documented in 33 of 34 (97%) homosexual and bisexual men, but only 6 of 15 (40%) individuals with other probable routes of infection. Thirty of the 39 subtype B sequences were joined in a tight sequence cluster that also included sequences from neighboring Russia and Lithuania. This pattern suggests a local spread of HIV-1 among homosexual and bisexual men within the region. The results from the phylogenetic analyses agreed well with other epidemiological information. In conclusion, Estonia remains a country with a low prevalence of HIV infection. A majority of the identified cases are homosexual or bisexual men, whereas HIV infection among intravenous drug users is rare. A large proportion of the homosexual and bisexual men carried closely related subtype B variants. The sequences have been deposited in GenBank under accession numbers AF286538-AF286586.

Hepatitis C virus genotypes in Estonia

Distribution of hepatitis C virus (HCV) geno(sub)types among 215 Estonian patients hospitalized with acute or chronic hepatitis and with HCV RNA-positive sera was investigated. For genotyping, both multiplex PCR with subtype-specific primers of the core region and RFLP analysis of cDNA of the 5' NCR region were used. These two methods permitted a correct characterization of genotypes, a more truthful characterization of mixed infections, and combined use of single-tube performances. They revealed, respectively, 200 and 202 (93.0% and 93.9%) HCV-positive samples of sera, subtype 1a- 0.9% and 0.9%, 1b- 56.3% and 64.2%, 3a- 13.9% and 22.3%, 2a- 6.5% and 5.6%, type 4 0.5% and 0%, mixed infections- 13.5% and 0%, and unidentified- 1.4% and 0.9%. In the majority of cases (84.7%) both methods gave completely or partially concordant results; in mixed infections, as determined by subtype-specific PCR, only one subtype was revealed by the RFLP method. In the remaining 15.3% of the cases (Ohno- 7.0%, RFLP- 8.3%) only one of the methods was positive. The epidemiological analysis of the dynamics of the subtypes' relative participation may indicate increasing 3a and decreasing 1b subtype infection during recent years.

Could long-term alimentary iron overload have an impact on the parameters of oxidative stress? A study on the basis of a village in southern Estonia

The effects of long-term alimentary (drinking water) iron overload on the parameters of oxidative stress were evaluated. The study group (n = 35) from a village in southern Estonia was 37.1 +/- 13.3 years old, and the mean period of drinking water iron overload was 20.6 +/- 9.3 years. The serum iron content was significantly higher than normal. The total iron-binding capacity of serum tended to be lowered. There was no change in the transferrin content. The parameters of lipid peroxidation like conjugated dienes and thiobarbituric acid reactive substances showed also significant differences. In addition, the red blood cell glutathione content was also decreased. The total antioxidant capacity of serum was not changed. It can be concluded from our results that a long-term alimentary iron overload results in a positive serum iron balance, which, in turn, yields an increased oxidative stress.

Effect of low-dose aspirin on the markers of oxidative stress

The present study estimates effects of low-dose enteric coated aspirin (ECA) on oxidative stress (OS) markers in a group of middle-aged men (mean age 51.2 +/- 6.9 years) free of pre-existing ischemic heart disease.

METHODS

Serum products of lipid peroxidation, and measures of antioxidative status were detected in 25 healthy men in baseline and after two-week treatment period.

RESULTS

In respect to serum products of lipid peroxidation and markers of antioxidant status, no statistically significant differences between the pre- and after-treatment data were observed for any measures, with the exception of values of serum antioxidative capacity (39.0 +/- 2.5 and 42 +/- 4.6, respectively).

CONCLUSIONS

Administration of ECA does not initiate the OS in blood and improves the general antioxidative potency of blood. This may imply towards certain antiatherogenic influence of low-dose ECA, exhibited even with a short-term treatment period. Regarding OS markers, a variety of individual responses observed in the selected subgroups should be investigated and possibly taken into account while treatment with ECA is initiated for primary prevention of cerebrovascular events.

Changes of sympatho-adrenal and hypothalamo-pituitary-adrenocortical system in patients with head injury

To determine the role of the sympatho-adrenal (SAS) and hypothalamo-pituitary-adrenocortical system (HPAS) after head injury, the relationship between venous blood epinephrine (E), norepinephrine (NE), adrenocorticotropic hormone (ACTH), cortisol levels, and clinical condition was examined in 55 patients. These observations suggest that head injury causes mainly activation of the above-mentioned systems depending on the severity of trauma. An inverse correlation between the levels of E, NE and Glasgow Coma Scale score, indicating the severity of head injury was revealed. ACTH and cortisol were similarly related to the clinical condition, although the observed correlation was less expressed. The changes in hormonal levels were present during the whole research period (1 week), although a certain shift to normalization was observed. However, catecholamines and ACTH levels in plasma were relatively low in severely head-injured patients whose CT scans revealed serious alterations in the mesencephalic-diencephalic area. At the same time their cortisol levels obtained maximal values and their chance to survive was diminutive. The results of this study indicate that investigation of hormones of SAS and HPAS might be useful as an additional method in the complex of ordinary examinations in establishing early prognosis in patients with brain injury.

Time course of oxidative stress during open-heart surgery

Oxidative stress and subsequent lipid peroxidation have been suggested as pathogenetically important for postischaemic reperfusion injury. We studied the time-course of oxidative stress in 14 adults undergoing cardiac surgery, evaluating serum levels of lipid peroxidation products--diene conjugates (DC) and basal and Fe-stimulated thiobarbituric acid reactive substances (TBARS, FeTEBARS)--as well as markers of blood antioxidant status--serum antioxidative capacity (AOC) and red blood cell glutathione (RBC-GSH) at 6 perioperative time-points. Arterial TBARS were significantly increased 15 minutes after start of cardiopulmonary bypass, 5 minutes after release of aortic cross-clamp and 15 minutes after cessation of bypass, compared with the preoperative levels (respective means 20.8, 38.5, 34.8 vs 7.5 nmol/g protein, p < 0.05). AOC had decreased at these times (means 21.3, 18.1, 23.2 vs 34.9%, p < 0.05). The TBARS changes correlated with AOC decrease (r = 0.30, p < 0.001). Changes in serum DC and RBC-GSH were not statistically significant. All lipid peroxidation parameters had returned to preoperative levels on the following morning, while antioxidative capacity remained suppressed (28.1%, p < 0.05). These data demonstrate a definite time-course of oxidative stress markers in arterial blood during open-heart surgery.

Possible imbalance of the immuno-hormonal axis in multiple myeloma

A comparative study of some immunologic aspects and hormonal balance was performed on 49 multiple myeloma (MM) patients and 29 healthy persons. Functional immunoregulatory imbalances were evident in the majority of patients with MM, as demonstrated by a significant reduction in the mitogenic response of peripheral blood lymphocytes (PBL) to phytohemagglutinin, increased mean stimulation indices of PBL to pisum sativatum agglutinin, wheat germ agglutinin (WGA) and dextran sulphate. Our results appear to provide important evidence in support of the existence of hormonal imbalance in MM: increased cortisol levels, augmented concentrations of follicle stimulating hormone, luteinizing hormone and 17 beta-estradiol and an increased estrogen to androgen ratio in male patients; decreased estrogen values and estrogen to androgen ratios were evident in female patients. Triiodothyronine and thyroxine mean concentrations were also found to be markedly diminished in MM patients. Our studies suggest some potentially important interactions between the immune and endocrine systems in multiple myeloma.

Thyroid control of contractile function and calcium handling in neonatal rat heart

Newborn rats were rendered hyperthyroid (daily subcutaneous injections of L-triiodothyronine, 10 micrograms 100 g-1 body weight) or hypothyroid (0.05% 6-n-propyl-2-thiouracil in drinking water to nursing mothers) during the first 3 weeks of postnatal life. Compared with the euthyroid group, hyperthyroidism resulted in: (1) cardiac enlargement with right ventricular preponderance, (2) increased cardiac contractile function, (3) increased Ca2+ uptake by the sarcoplasmic reticulum (SR), (4) decreased sensitivity to the negative inotropic effect of verapamil and (5) greater inhibition of contractile function by ryanodine. Hypothyroidism generally resulted in opposite changes. The data suggest that the development of the heart and its contractile function during early postnatal life depends on the plasma level of thyroid hormones. In particular, the relative contribution of the SR and sarcolemmal Ca2+ transport to the control of cardiac contractility seems to be markedly affected by altered thyroid states. The postnatal maturation of the SR function is accelerated in hyperthyroidism but retarded in hypothyroidism. Consequently, hyperthyroid hearts appear to be less dependent and hypothyroid ones more dependent on trans-sarcolemmal Ca2+ fluxes when compared with age-matched euthyroid animals.

Recurrent ulceration after proximal gastric vagotomy. Possible role of mucosal barrier

Between 1971 and 1986 532 proximal gastric vagotomies were carried out at the Pelgulinna Hospital. The five-year recurrence rate was 5.5% (n = 29). We have studied 40 patients with chronic duodenal ulceration, 20 patients who had effective proximal gastric vagotomy, and seven patients who presented with recurrent ulcers after proximal gastric vagotomy. Patients who had positive Hollander tests after vagotomy, and those with disorders of gastric motility, were excluded. In the group with recurrent ulcers the concentration of neutral mucopolysaccharides in the gastric juice was significantly lower than in the other two groups, and it correlated with the amount of material showing a positive reaction to periodic acid Schiff (PAS) in the gastric mucosa. This group also had significantly higher mean serum gastrin concentrations and mast cell degranulation rates in the mucosa of the fundus and the antrum. We conclude that qualitative changes in the production of gastric mucus lead to defective functioning of the mucosal barrier in patients with recurrent ulcers and may be one of the causes of recurrences.

Distribution of serum gastrin in different forms of gastritis among Estonian population

Gastrin level was measured in frozen serum samples of 215 adult Estonians, who took part in a representative population study in 1979, and were followed-up in 1985. Gastric morphology was verified by multiple biopsy specimens from the fundal and antral parts of the stomach, obtained at direct-vision gastroscopy. Certain combinations of antral-body mucosa were revealed which have, and which do not have a significant influence on the fasting gastrin levels. Low values might be observed in subjects having severe atrophic gastritis simultaneously in fundal as well as in antral area. However, in others low concentration of gastrin was seen without any (or without severe) changes of the mucosa. Therefore different factors as duodenal gastrin-producing cells, several molecular forms of gastrin, age of the person seems to contribute to the total serum gastrin level besides the gastric mucosa. High values of gastrin are characteristic to normal antral mucosa accompanied by moderate or severe fundal gastritis.