Markers of oxidative stress before and after exchange transfusion for neonatal sepsis

Oxidative status before and after ET was assessed in eight septic newborns who received exchange transfusion (ET). Short-term elevations of conjugated dienes (CDs) and thiobarbituric acid reactive substances (TBARSs) (p < 0.05) and increased serum antioxidant capacity (AOC) (p = 0.06) were noted. Chromatographic migration of the red blood cells (CM RBCs), a measure of RBC deformability, also improved after ET. ET for neonatal sepsis does not cause significant oxidative stress; rather, it may help to restore the antioxidant depots and improve RBC deformability and microcirculation.     

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

Newborn rats were rendered hyperthyroid (daily subcutaneous injections of L-triiodothyronine, 10 g 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.     

Use of nonbreakpoint DNA probes to detect the t(X;18) in interphase cells from synovial sarcoma: implications for detection of diagnostic tumor translocations.

Fluorescence in situ hybridization studies using non-breakpoint DNA probes were performed to detect the X;18 translocation on 4-microm sections of synovial sarcoma from paraffin blocks. This was done by using commercially available, large target unique sequence DNA probes for regions of the X chromosome short-arm and the 18 chromosome long-arm together with centromere probes for the alternate chromosomes. We determined that such probe combinations could detect the presence of the diagnostic X;18 translocation in interphase cells. Spatial association of dual color signals from the X centromere and the 18 unique sequence probe, as well as between an 18 centromere and the X unique sequence probe, was seen in a significantly higher percentage of synovial sarcoma cells (81.1% +/- 7.7%, confidence interval 95%) than in control nonsynovial soft tissue sarcomas (14.7% +/- 8.3%) and control peripheral blood lymphocytes (5.6% +/- 0.6%). The observed spatial association supports the use of this strategy to detect the X;18 translocation in synovial sarcoma and suggests that this technique could be applied in the diagnosis of other types of tumors with characteristic translocations when histopathological findings are inconclusive. This study is the first report describing the use of nonbreakpoint unique sequence probes for detecting translocations in tumors on paraffin-embedded slides.     

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.     

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 continously 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.     

CC-chemokine receptor CCR5-del32 mutation as a modifying pathogenetic factor in type I diabetes

The purpose of this study was to determine the CCR5-del32 allele frequency in type I (insulin-dependent) and type II (noninsulin-dependent) diabetes patients, and to test whether and how this mutation is associated with both types of diabetes. Thirty-eight type I diabetes and 111 type II diabetes patients' genotyping was performed by polymerase chain reaction assaying, and amplified products were digested with restriction enzyme EcoRI. The results were analyzed using statistical methods. No statistical differences were found in CCR5-del32 allele frequencies in types I and II diabetes patients compared with the control group of native Estonians. However, an association exists between CCR5 gene polymorphism and the clinical course of type I diabetes. In the case of wild-type CCR5, the disease starts at an earlier age. In type II diabetes, there was a difference between genotypes in morbidity to concomitant diseases, being higher in the CCR5 wild-type genotype.     

Nickel sulphate and epoxy resin: differences in iron status and glutathione redox ratio at the time of patch testing

The reactive patch test reaction is a useful model to characterize oxidative stress in acute allergic contact dermatitis. This model was used to study oxidative stress in the skin of individuals allergic to nickel and epoxy resin. The study included six and five patients, respectively, whose skin was simultaneously biopsied from a positive patch test site and from an apparently healthy area. The biopsies were homogenized and used for determination of iron content, unbound iron binding capacity, diene conjugate levels, and glutathione redox ratio. A positive test reaction to 5% nickel sulphate was accompanied by 2.5-fold increase in iron level as compared to apparently healthy skin (P<0.1). The percentage saturation of iron-binding capacity and the glutathione redox ratio were significantly increased (P<0.01 and P<0.05, respectively). Reactive patch test responses to 1% epoxy resin were not accompanied by clear alterations in iron status or glutathione redox ratio. Our investigation showed that apart from oxidative burst caused by accumulation of inflammatory cells, hapten properties might also influence the oxidative stress status of the skin. The high incidence of nickel allergy may be attributed, at least in part, to the influence of nickel ions on the glutathione redox ratio and iron status of the skin.     

Beneficial effects of water-based exercise in patients with chronic kidney disease

The possible beneficial effect of regular aquatic exercise on cardiorespiratory, renal lipid parameters and oxidative stress status was studied in patients with mild to moderate renal failure. The exercise group did low-intensity aerobic exercise in the pool during a period of 12 weeks, twice a week, with sessions lasting for 30 min. Matched control participants remained sedentary. The results showed that in the exercise group all cardiorespiratory functional parameters improved and resting blood pressure lowered significantly. Proteinuria and cystatin-C were diminished significantly and glomerular filtration rate was enhanced. To evaluate the changes in oxidative stress status in the serum, products of lipid peroxidation (LPO) and serum glutathione values were measured. LPO was reduced significantly and reduced glutathione levels showed significant improvement after the exercise-conditioning programme. In the control group the data either remained the same or worsened in the same period of time. In conclusion, regular water-based exercise has beneficial effects on the cardiorespiratory, renal functional parameters and oxidative stress status in patients with moderate renal failure, and can be used in the complex rehabilitation of chronic renal failure patients, together with blood pressure control, dietary consultation, encouragement and education to prevent physical worsening and to postpone cardiovascular and renal atherosclerotic complications.     

Endothelial function, CRP and oxidative stress in chronic kidney disease

BACKGROUND: Chronic kidney disease (CKD) is associated with increased morbidity and mortality in cardiovascular disease (CVD). Apart from traditional risk factors, chronic inflammation, oxidative stress, malnutrition and endothelial dysfunction are important in CVD development in renal patients. Our aim was to investigate the relationship between high sensitivity C-reactive protein (CRP), endothelium dependent vasodilation (EDV) and oxidative stress markers in patients with CKD K/DOQI stage 3-5. METHODS: Measurements of CRP, conjugated dienes (CD), lipid hydroperoxide (LOOH), oxidized low density lipoprotein,glutathione and albumin were performed in 44 consecutive patients with CKD stage 3-5. EDV was measured by methacholine infusion in the brachial artery and venous occlusion plethysmography. RESULTS: Patients with high CRP had significantly lower glomerular filtration rates and albumin, but increased LOOH and CD. In multiple regression analysis, only LOOH and CD remained significant. Patients with poor EDV had increased urea and lower glutathione (GSH). In multiple regression analysis, GSH and urea were independently related to EDV. No correlation was found between CRP and endothelial function. CONCLUSION: CRP was related to lipid peroxidation, while endothelial function was related to intracellular oxidative stress in patients with CKD. CRP and EDV were unrelated to each other. Therefore, CRP and endothelial function could provide complementary prognostic information regarding future cardiovascular disorders in renal patients.     

Preoperative methylprednisolone does not reduce loss of knee-extension strength after total knee arthroplasty

Background and purpose — Patients undergoing total knee arthroplasty (TKA) face challenges related to postoperative reduction in knee-extension strength. We evaluated whether inhibition of the inflammatory response by a single preoperative dose of methylprednisolone (MP) reduces the pronounced loss of knee-extension strength at discharge after fast-track TKA.

Patients and methods — 70 patients undergoing elective unilateral TKA were randomized (1:1) to preoperative intravenous (IV) MP 125?mg (group MP) or isotonic saline IV (group C). All procedures were performed under spinal anesthesia without tourniquet, and with a standardized multimodal analgesic regime. The primary outcome was change in knee-extension strength from baseline to 48?hours postoperatively. Secondary outcomes were knee joint circumference, functional performance using the Timed Up and Go (TUG) test, pain during the aforementioned tests, rescue analgesic requirements, and plasma C-reactive protein (CRP) changes.

Results — 61 patients completed the follow-up. The loss in quadriceps muscle strength was similar between groups; group MP 1.04 (0.22–1.91) Nm/kg (–89%) vs. group C 1.02 (0.22–1.57) Nm/kg (–88%). Also between-group differences were similar for knee circumference, TUG test, and pain scores. MP reduced the inflammatory response (CRP) at 24?hours postoperatively; group MP 33 (IQR 21–50) mg/L vs. group C 72 (IQR 58–92) mg/L (p < 0.001), and 48?hours postoperatively; group MP 83 (IQR 56–125) mg/L vs. group C 192 (IQR 147–265) mg/L (p < 0.001), respectively.

Interpretation — Preoperative systemic administration of MP 125?mg did not reduce the pronounced loss of knee-extension strength or other functional outcomes at discharge after fast-track TKA despite a reduced systemic inflammatory response.