[Prostate cancer detection rates: comparison of standard biopsy with prompt rebiopsy and a one-time extended biopsy]. / Prostatakarzinomdetektionsraten : Vergleich zwischen der Standardbiopsie mit zeitnaher Rebiopsie und einer einmaligen extendierten Biopsie.

INTRODUCTION: Prostate biopsy is the gold standard for the detection of prostate cancer (PCA). While national and international guidelines recommend the extraction of 10-12 cores at initial biopsy, some authors plead to initially perform more extensive biopsy protocols. We assessed the PCA detection and complication rates of different biopsy schemes. MATERIALS AND METHODS: We relied on the data of 425 men who underwent their first prostate biopsy from April 2005 to May 2013. Exclusion criteria consisted of PSA > 20 ng/ml, prior surgery of the prostate, or intake of 5-α-reductase inhibitors. Overall 357 underwent a 10- to 12-core biopsy, while 68 patients underwent 20-core biopsy. In case of a negative biopsy in the 10-12 cohort, rebiopsy was performed within 6 months, while in the 20-core group clinical follow-up determined further course of action. Endpoints of the study were the overall PCA detection rate and the rate of severe complications, which were defined as complications requiring hospital admission. The effect of the respective biopsy scheme on the PCA detection rate was assessed using uni- and multivariable logistic regression analysis. In the subanalysis, the PCA detection rates between the two groups were compared solely in patients with PSA values ≤10 ng/ml. RESULTS: At initial biopsy, the overall PCA detection rate was 50.4% (214/425). In the 10-12 core group, the PCA detection rate at first biopsy was 52.4% (187/357) and rebiopsy detected a further 19 (11.2%) PCA cases, resulting in a cumulative PCA detection rate of 57.7% (206/357). In the 20-core group, the PCA detection rate was 39.7% (27/68). While the different PCA detection rates were not statistically different when the initial biopsies were compared, biopsy scheme reached independent predictor status when the cumulative PCA detection rate of the 10- to 12-core scheme was compared to the 20-core scheme (p=0.01). Comparable results were obtained only when patients with PSA ≤10 ng/ml were considered. The rate of severe complications was statistically higher in the 20-core group (6.1 vs. 2.4%; p=0.01). CONCLUSION: Our data indicate that an initial 20-core biopsy does not lead to a higher PCA detection rate compared to an initial 10- to 12-core biopsy. Moreover, the cumulative PCA detection rate of a 10- to 12-core biopsy and prompt repeat biopsy was significantly higher compared to a single 20-core biopsy.

Decreased level of endogenous secretory receptor for advanced glycation end-products in diabetes with concomitant hyperlipidemia.

Endogenous secretory receptor (esRAGE) for advanced glycation end-product (AGE) acts as decoy for AGEs. The AGE-to-esRAGE ratio was hypothesized to be implicated in diabetic vasculopathy. We investigated an association of esRAGE and methylglyoxal-adducts serum level, as well as AGE-to-esRAGE ratio in subpopulation of diabetic patients with or without concomitant hyperlipidemia and macrovascular disease in history. In diabetes with concomitant hyperlipidemia esRAGE was significantly decreased compared to hyperlipidemia with normal glucose metabolism (0.306+/-0.2 vs. 0.367+/-0.1; p=0.019) or diabetes alone (0.306+/-0.2 vs. 0.404+/-0.1; p=0.004). High AGE/esRAGE ratio, found in diabetic patients with hyperlipidemia, pointed to increased production of AGEs and low expression of esRAGE. In multivariable analysis adjusted for several confounding factors, increased AGE/esRAGE ratio was recognized as a high risk for vascular disease outcomes.

Glycotoxines, carbonyl stress and relevance to diabetes and its complications.

A large body of evidence has implicated reactive carbonyl compounds as glycotoxic mediators of carbonyl stress. This review is focused on the pathophysiological effects of alpha oxoaldehydes in diabetes and related complications, summarizing the state-of-the-art on the endogenously produced carbonyls methylglyoxal, glyoxal and 3-deoxyglucosone, formed as glycolytic intermediates during metabolic conversion of glucose, via Maillard reaction by degradation of glycated proteins, and during lipid peroxidation process. Their role in the advanced glycation process and detrimental effects on vascular tissue are discussed.

Infrared thermography based on artificial intelligence as a screening method for carpal tunnel syndrome diagnosis.

This study further evaluated a computer-based infrared thermography (IRT) system, which employs artificial neural networks for the diagnosis of carpal tunnel syndrome (CTS) using a large database of 502 thermal images of the dorsal and palmar side of 132 healthy and 119 pathological hands. It confirmed the hypothesis that the dorsal side of the hand is of greater importance than the palmar side when diagnosing CTS thermographically. Using this method it was possible correctly to classify 72.2% of all hands (healthy and pathological) based on dorsal images and > 80% of hands when only severely affected and healthy hands were considered. Compared with the gold standard electromyographic diagnosis of CTS, IRT cannot be recommended as an adequate diagnostic tool when exact severity level diagnosis is required, however we conclude that IRT could be used as a screening tool for severe cases in populations with high ergonomic risk factors of CTS.

The role of procalcitonin in gynaecological surgery.

We evaluated postoperative concentrations of inflammatory indicators, including procalcitonin, after gynaecological operations for benign and malignant tumours in patients with a normal postoperative course and assessed the utility of procalcitonin in differentiating between non-bacterial inflammation and bacteraemic complications in the postoperative period. This prospective study included 99 patients: 47 after a standard gynaecological operation (Piver I) and no postoperative infectious complications (group 1), 35 after a major procedure (Piver II or III) and no postoperative infectious complications (group 2), and five with postoperative sepsis after Piver II or III procedures (group 3). We also studied serum procalcitonin concentrations in a group of 12 patients (group 4) with terminal forms of gynaecological cancer who were hospitalized for palliative treatment but did not undergo surgery. Postoperative C-reactive protein (CRP) concentration corresponded with extent of tissue trauma in groups 1 and 2 and was significantly lower in group 1 than group 2. Inflammatory indicators were highest in groups 1 and 2 on postoperative day 2. In group 3, in which sepsis developed, values were highest on postoperative day 4. In particular, procalcitonin was > 2 ng/ml in all patients with postoperative sepsis by postoperative day 2 but was always 2 ng/ml, with no signs of infection or raised CRP. It is concluded that, for early detection of postoperative infectious complications after gynaecological surgery, procalcitonin levels > 2 ng/ml are more specific than CRP.

Infrared thermography based on artificial intelligence for carpal tunnel syndrome diagnosis.

Thermography for the measurement of surface temperatures is well known in industry, although is not established in medicine despite its safety, lack of pain and invasiveness, easy reproducibility, and low running costs. Promising results have been achieved in nerve entrapment syndromes, although thermography has never represented a real alternative to electromyography. Here an attempt is described to improve the diagnosis of carpal tunnel syndrome with thermography using a computer-based system employing artificial neural networks to analyse the images. Method reliability was tested on 112 images (depicting the dorsal and palmar sides of 26 healthy and 30 pathological hands), with the hand divided into 12 segments and compared relative to a reference. Palmar segments appeared to have no beneficial influence on classification outcome, whereas dorsal segments gave improved outcome with classification success rates near to or over 80%, and finger segments influenced by the median nerve appeared to be of greatest importance. These are preliminary results from a limited number of images and further research will be undertaken as our image database grows.

Elevated level of methylglyoxal during diabetic ketoacidosis and its recovery phase.

Carbonyl stress is hypothesized to be an associated complication of diabetic ketoacidosis. The production of the glycolytic intermediate methylglyoxal (MG) was followed up in 7 diabetic patients treated for ketoacidosis during pretreatment and recovery phase. Blood samples for methylglyoxal analysis were collected upon patient arrival in emergency department (0 h), and during ketoacidosis treatment between 12-24 h and at 168 h. The study also included 10 normoglycaemic healthy volunteers and 31 type 1 diabetic patients (control diabetes group). The methylglyoxal assay, based on methylglyoxal derivation with 1,2-diamino-4,5-dimethoxybenzene (DDB), was performed by HPLC, only assessing the level of free methylglyoxal. The baseline level of methylglyoxal recorded in normoglycemic healthy controls was 338 +/- 62 nmol/l versus 374 +/- 89 nmol/l in control diabetes group (P = 0.0407). A consistent feature of diabetic ketoacidosis before and during treatment was striking elevation of methylglyoxal as compared with control diabetes group (median test chi(2) = 14.6, df = 3, P = 0.0021). Friedman's ANOVA indicated differences (P = 0.04) among the three sampling times with a peak value (601 +/- 95 nmol/l) at 12-24 h following therapy initiation. However, fasting treatment values at 168 h were still significantly higher than the mean fasting methylglyoxal level in control diabetes group (P = 0.008). The study indicated that diabetic ketoacidosis results in an increase in methylglyoxal level. Excessive production of toxic intermediates such are alpha-dicarbonyls may be a link connecting an acute metabolic event with accelerated tissue damage, a feature characteristic of long-term complications of diabetes.

Urinary excretion of advanced glycation endproducts in patients with type 2 diabetes and various stages of proteinuria.

OBJECTIVE: The objective of the study was to detect AGE-immunoreactive proteins in urine, and to evaluate AGE excretion at various stages of diabetic nephropathy in type 2 diabetes assessed by the level of proteinuria. METHODS: AGEs were measured in 24-h urine collection of patients with normoalbuminuria (N) (n=22), microalbuminuria (Mi) (n=31), macroalbuminuria (Ma) (n=28), and overt proteinuria with elevated serum creatinine level (PC) (n=25). A competitive ELISA with polyclonal anti-AGE antibodies was used to monitor AGE excretion. RESULTS: Multiple comparison of urine AGE content among various stages of proteinuria showed significant differences (summary p<0.000). Fifty percent of samples from the group of normoalbuminuric, and only 15% of samples from the group of microalbuminuria patients were AGE negative. However, there was no significant difference in AGE excretion between the patients with persistent proteinuria and elevated serum creatinine, and those with macroalbuminuria (PC vs Ma, p=0.265). None of the samples from these two groups of patients with highest AGE content in 24-h urine was negative for AGE-immunoreactivity. In addition, the ratio between 24-h urinary AGEs and urinary albumin excretion was calculated to determine whether total 24-h urinary AGE content is an index of the toxic form of albumin released in the course of diabetic nephropathy. The ratio values were log-transformed and bivariate comparison showed significant differences between the N vs Mi (p=0.006) and Mi vs Ma (p=0.000) groups. However, there was no significant difference (p=0.407) between values in the Ma and PC groups of patients. Multiple stepwise regression analysis indicated a relationship of urinary AGE-immunoreactivity with creatinine clearance values (r=0.52, p<0.001). CONCLUSION: The study demonstrated the presence of AGE-immunoreactivity in the urine of diabetic patients with various stages of proteinuria. Study results pointed to creatinine clearance as the main predictor of AGE excretion. Therefore, the measurement of urinary AGE appears to offer limited extra information in patients with impaired renal function.

Advanced glycation endproducts in peripheral nerve in type 2 diabetes with neuropathy.

Advanced glycation endproducts (AGE) accumulate over proteins as a consequence of diabetic hyperglycemia, and thus contribute to the pathogenesis of diabetic complications. To improve the understanding of the pathology of diabetic neuropathy, AGE accumulation was analyzed in sural and/or femoral nerves obtained under spinal anesthesia from 8 type 2 diabetic patients with both distal symmetrical polyneuropathy and proximal neuropathy. Pronounced AGE immunoreactivity was detected on axons and myelin sheaths in 90% of diabetic peripheral nerves but not in the control specimen. The intensity of axonal AGE immunopositivity significantly correlated with the severity of morphological alterations (p<0.005). AGE localization, demonstrated by immunohistochemical methods, was also present in the endoneurium, perineurium and microvessels. Morphometric analysis of the diabetic peripheral nerve showed perineurial thickening (diabetic vs. control, 15.5+/-4.9 vs. 6.6+/-2.1 microm, p<0.001), narrowing of the microvessel lumina (66.6+/-50.5 vs. 579.5+/-38.4 x10(3) microm(2), p<0.001) and significant reduction in the number of preserved axons (3.6+/-3 vs. 8.9+/-2.3 per 10(5) microm(2) per area, p<0.037). The sera of diabetic patients contained epitope(s) of AGE structure and soluble immune complexes containing AGE moiety. In conclusion, to the best of our knowledge, this is the first study providing evidence for excessive AGE formation on peripheral nerve components, primarily axons, and a significantly higher level of circulating AGE-immune complexes in patients with both distal diabetic polyneuropathy and proximal neuropathy. Humoral immune mechanisms, including the production of anti-AGE autoantibody, may potentially be involved in the development of structural abnormalities described in this report.

Products of advanced glycation in patients with type 2 diabetes and vascular disease.

BACKGROUND: Non-enzymatic glycation leading to advanced glycation endproduct (AGE) formation is thought to contribute to vascular pathology. In the present study, AGEs and anti-AGE antibodies in free and immune complex-bound form were assayed in the serum of diabetic (DMCAD) (n = 69) and nondiabetic (n = 78) patients with coronary artery disease (CAD) and in control subjects (n = 47) free from vascular disease. METHODS: A blocking enzyme-linked immunosorbent assay (ELISA) was used to test immunoreactivity against AGE epitope(s) and a competitive ELISA was used to measure total AGE content. RESULTS: Anti-AGE immunoreactivity was significantly higher in diabetic than in control subjects (P = 0.045). Although a wide range of anti-AGE antibody titres were observed in nondiabetic CAD patients, there was no significant difference from those of control subjects. Both diabetic and nondiabetic CAD patients had a higher concentration of circulating immune complexes containing the AGE moiety as antigen than did control subjects (DMCAD versus control, P = 0.041; CAD versus control, P = 0.047). Study patients showed a positive correlation between serum AGE and AGE-immune complexes (DM, r = 0.29, P = 0.014; CAD, r = 0.26, P = 0.019), whereas no such correlation was recorded in controls (r = 0.08, P = 0.89). CONCLUSION: To our knowledge, this is the first study demonstrating increased AGE-immune complexes in patients with CAD, either with or without diabetes, suggesting that AGE-immune complexes might be involved in the atherosclerotic process, either as the result of it or as part of the pathophysiologic process.

Soluble LDL-immune complexes in type 2 diabetes and vascular disease.

BACKGROUND AND AIMS: The oxidative modification of LDL has been shown to affect its clearance and to exert cytotoxic and immunogenic effects. The objective of our study was to analyse markers of LDL oxidation-soluble LDL containing immune complexes (LDL-ICs) in type 2 diabetes with micro- and macrovascular disease. PATIENTS AND METHODS: The study included 69 diabetic patients with coronary artery disease (DM + CAD), 78 non-diabetics with CAD, 47 controls, and 27 diabetics with nephropathy and 36 free from complications. OxLDL antibodies and advanced glycated end-products were measured by ELISA, and LDL-IC apo B content after PEG precipitation. RESULTS: Determination of a broad range of oxLDL antibody activity in all study groups showed no significant differences. In contrast, the content of apo B, a component of the antigen moiety of oxLDL-ICs, was higher in CAD and diabetes (+ CAD) than in LDL-ICs isolated from controls (p < 0.001). LDL-ICs did not differ between patients with CAD + DM and CAD patients free from diabetes. LDL-IC levels in diabetic patients with or without microangiopathy were significantly higher than in healthy volunteers (PEG-apo B 0.278 +/- 0.107 vs. 0.165 +/- 105 g/l, p < 0.002; PEG-IgG 151.7 +/- 76 vs. 115.4 +/- 62 g/l, p < 0.05). However, there was no significant difference in the level of circulating LDL-ICs between the subgroup of diabetic patients with nephropathy/retinopathy and patients free of microvascular disease (Ab-oxLDL 27.7 +/- 10.4 vs. 27.1 +/- 9.3 AU, NS; PEG-apo B 0.324 +/- 0.111 vs. 0.287 +/- 0.124 g/l, NS; PEG-IgG 1.68 +/- 0.68 vs. 1.42 +/- 0.80 g/l, NS). There was a statistically significant positive correlation between AGE content and LDL-ICs (r = 0.35, p < 0.009). A significant but inverse correlation was recorded between triglyceride concentration and level of LDL-ICs in DM + CAD (r = - 0.32, p < 0.016) and CAD patients (r = - 0.35, p < 0.002). A highly significant negative correlation between triglycerides and circulating LDL-ICs (r = - 0.54, p < 0.039) was observed in patients with early nephropathy, but not in those with physiological proteinuria. It is known that at a high triglyceride level in type 2 diabetes, the majority of LDL are small and dense, thus being more susceptible to oxidative modification. This could be a possible mechanism explaining why more LDL-ICs, with a level inversely correlating with triglyceride concentration, are generated in diabetes. CONCLUSION: The increased level of circulating LDL-ICs is a risk factor for the general population, including those with diabetes. Our results suggested the contribution of LDL-ICs to the development of atherosclerosis to probably be more significant than the direct contribution of oxLDLAb itself.

Detection of autoantibodies against advanced glycation endproducts and AGE-immune complexes in serum of patients with diabetes mellitus.

Advanced glycation of protein causes their immunogenicity. The evidence that advanced glycation endproducts (AGEs) have antigenic properties has led to a hypothesis that the AGE structure found in vivo may exert an autoimmune response. In the present study, we showed the sera of diabetic patients as well as of nondiabetic individuals to contain autoantibodies to epitopes of AGE structures. Contrary to what might be expected, we observed lower AGE antibody titers in diabetic subjects, and postulated that the antibodies against AGEs form immune complexes in vivo, hampering their determination. The existence of immune complexes containing AGE moiety was established by two independent criteria: (a) serum AGE-immune complexes (AGE-IC) were detected by enzyme-linked immunosorbent assay (ELISA) using an immunochemical bridge; and (b) soluble AGE-IC were precipitated from serum by polyethylene glycol and analyzed. We demonstrated the presence of circulating AGE-IC in sera, predominantly in the sera of diabetic subjects. We also found an inverse correlation between serum AGE level and AGE-IC (r=-0.8, P<0.000), indicating the serum level of AGEs to decline with an increasing presence of AGE-IC. The content of AGE in soluble immune complexes was significantly higher in diabetic patients than in control subjects (3.51+/-1.9 vs. 1.89+/-1.0 microgEq/ml (P<0.00004), and correlated inversely with free antibodies (r=-0.26, P<0.01). Interactions of AGE autoantibodies with AGE as a continuously produced antigen result in the formation of AGE-immune complexes that may play a role in the atherogenic processes.

Ultrasonographic assessment of celiac disease in children: comparison with antiendomysium antibodies and histology.

UNLABELLED: Several attempts have been made to identify accurate screening tests for celiac disease (CD) with the aim to reduce the need for biopsy or obtaining appropriate selection criteria prior to intestinal biopsy. In this context we evaluated the usefulness of screening for endomysial antibodies (EMA) in the diagnosis of CD in children in comparison with CD-related changes detected by ultrasound (US) or biopsy. PATIENTS: We studied 35 children (1-15 years, 22 girls and 13 boys, mean age 8 years) with untreated CD (N = 15), treated CD (N = 10) and controls (N = 10), undergoing small bowel biopsy as a diagnostic procedure. METHODS: US of the small bowel was performed prior to mucosa biopsy using a 4- or 7-MHz transducer of a computed sonography device. The thickness of the intestinal wall and small bowel motility were recorded. Simultaneously, all children had serum routinely sampled for IgA EMA. RESULTS: All controls had histologically normal small bowel mucosa, US showed a small bowel wall thickness of 1 mm with normal motility in 9 children and non-specific wall changes in 1 child. EMA was weakly positive in 1 of these, and negative in all other controls. Of 15 children with untreated CD, severe enteropathy and strongly positive EMA were found in 10 cases; in 5 children moderate enteropathy and positive EMA were detected. Severe US changes were found in all of these children (1.6 mm thickness of the intestinal wall, hyperperistalsis and abundant fluid in the bowel). Mild enteropathy was found in 10 children with treated CD (3 months of a gluten-free diet). EMA was positive in 2 children and weakly positive in 8. Non-specific US changes were found in 6 children. In conclusion, our results indicate that US provides valuable information on small-bowel wall structure and can help in decision making on the necessity of small bowel biopsy. The present study confirms a stronger correlation between EMA and CD than between US and CD.

[Bone healing and biochemical blood parameters after arteficial osteotomy of rabbits' femur treated by low-frequency magnetic field]. / Knochenbruchheilung und biochemische Blutparameter bei Kaninchen nach kuünstlicher Femurosteotomie im schwachen niederfrequenten Magnetfeld.

Aim of the study was to investigate the effect of magnetic fields on bone fracture healing and biochemical indices of bone turnover. Young male "White Newzealand Rabbits" were exposed after osteotomy of the femur of the hind-paw in narcosis for 31 days in a low-frequency magnetic field (field parameters: frequency 15.3 Hz, signal form: sine, magnetic field strength: 50 microT peak value). Eight animals each were assigned randomly for a single blind study to 3 groups. Controls were kept in a sham-exposition cage without magnetic field influence and were compared with a group in (Pseudo-) Helmholtz-coil arrangement with a horizontal magnetic field and a further group in a cylinder coil (vertical magnetic field). The daily duration of stay in the (sham-) exposition arrangements amounted to 30 minutes respectively. The activities of the alkaline phosphatase (AP) and creatinkinase (CK) were evaluated preoperatively, after the 19th and 31st experimental day, the callus density by means of computertomography after the 31st experimental day (two-tailed t-test). The densitometrically assessed callus densities of the magnetically treated groups were highly significant (p < 0.0001) compared with the controls. In spite of accelerated fracture healing the activities of the ALP were lower at both postoperative examinations than preoperatively, in the cylinder-coil the activity proved to be significantly lower (p < 0.05) compared with the controls after 31 days. Significant differences in CK were detected at no time. In conclusion, we confirm the positive magnetic field effects on fracture healing. The mechanisms of interaction of magnetic field and bone fracture healing remain to be clarified.

Rat tissue collagen modified by advanced glycation: correlation with duration of diabetes and glycemic control.

Collagenous proteins are especially prone to nonenzymatic glycation, because they contain several dibasic amino acid residues with free amino groups, have a very slow turnover rate, and are exposed to ambient levels of glucose. The aim of this study was to determine the time-dependent course of advanced glycation process in diabetic rats in relation to glycemic control and duration of diabetes, compared to age-matched controls. Immunochemical assay with antibodies to advanced glycation end products (AGE) was first developed to qualitatively detect and quantify the AGE formed in rat tendon and aortic collagen. Individual collagen samples were extracted by extensive pepsin and collagenase digestion. The amount of AGE was measured by competitive ELISA and results were expressed as AGE U/mg collagen. Diabetic rats showed a significant increase in AGE content in aortic collagen at 20 weeks (n = 6, 206.6 +/- 16.7 U/mg collagen) compared with that measured at 4 and 12 weeks (n = 6, 110 +/- 12.8 U/mg collagen, and n = 13, 184.9 +/- 12.3 U/mg collagen at 4 and 12 weeks, respectively; p < 0.001 between 20 weeks and 4 weeks; p < 0.01 between 20 weeks and 12 weeks). The amount of AGE in tendon collagen of diabetic rats increased from 1.9 +/- 0.38 U/mg at 4 weeks to 11.2 +/- 6.1 U/mg collagen at 20 weeks, p < 0.001. Considerable disparity was observed in the intensity of glycation between aortic and tendon collagen. AGE-content per mg of aortic collagen was several-fold to that found in tendon collagen (p < 0.001). To investigate the effect of glycemic control on the advanced glycation process, total aortic AGE-collagen content was compared between untreated diabetic rats (D; n = 13, 184.9 +/- 12.3 U/mg) and diabetic rats treated for 12 weeks with insulin (DI; n = 6, 133.9 +/- 10.7 U/mg), or phlorizin (DP; n = 6, 132.4 +/- 8.9 U/mg), or by a combination of insulin/phlorizin (DIP; n = 6, 124.3 +/- 6.5 U/mg). In spite of therapy used, all groups of diabetic animals had a significantly higher aortic AGE-collagen content than those in the nondiabetic control group (C: n = 8, 104.6 +/- 14.9 U/mg) of the same age (D, DI, DP, DIP vs. C, p < 0.001). Comparison between the mean levels of glycated hemoglobin (D: 5.62 +/- 0.38 % vs. C: 1.7 +/- 0.05%) and mean AGE levels in the studied group of animals yielded a very good exponential correlation (r = 0.89, p < 0.001). Glycation-derived late-stage collagen modification was detected by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and by immunoblotting confirmed to contain (an) AGE-structure(s). Our study provides strong immunochemical evidence of AGE formation in vivo during hyperglycemia, and of their temporal association with structural alterations of extracellular matrix proteins. The advanced glycation process is retarded and reduced in intensity, but not completely abolished, by glycemia regulation with, or independently of, insulin.

Changes of autoantibodies against oxidatively modified low density lipoproteins during long-term LDL-apheresis.

The oxidation of low-density lipoproteins (LDL) is considered a key event in the initiation of atherosclerosis. The aim of this study was to follow-up the biological marker of in vivo LDL oxidation (oxidatively modified LDL autoantibody titres) during long-term LDL-apheresis treatment. A patient suffering from severe combined hyperlipidaemia underwent LDL-apheresis biweekly and was followed for two years. The significant reduction of baseline total cholesterol (58%), total triglycerides (80%), LDL-cholesterol (48%), apoprotein B (50%) and apolipoprotein (a) (61%) may be considered as a good response to the treatment. The titre of autoantibodies (IgG) against oxidatively modified LDL (malondialdehyde-derived LDL) was followed throughout the study and showed dynamic changes. The measured values were multiple compared as mean+/-SD over each semester of apheresis application: I semester 70.0+/-8.3 U/ml, n = 12; II semester 58.0+/-13.8 U/ml, n = 12; III semester 37.6+/-6.0 U/ml, n=12; IV semester 34.3+/-7.0 U/ml, n = 12; ANOVA: I vs. II semester p<0.083, II vs. III semester p<0.00053, III vs. IV semester p<0.248. In parallel to the changes in this biochemical parameter, regression of numerous xanthomas was clinically observed. In spite of this, the presence of oxidised-LDL (oxLDL) antibodies was enhanced in comparison to antibody titre detected in a group of age-matched normolipaemic healthy controls (n = 15; 19.4+/-8.6; p<0.01). Classical lipoprotein parameters were correlated with the titre of autoantibodies against oxLDL and showed low correlation coefficients: total cholesterol vs. oxLDLab, r = 0.36; triglycerides vs. oxLDLab, r = 0.43; LDL cholesterol vs. oxLDLab, r = 0.14; HDL cholesterol vs. oxLDLab, r = -0.33; apo B vs. oxLDLab, r = 0.25; apo (a) vs. oxLDLab, r = -0.05. Our study showed an additional benefit of LDL-apheresis therapy. The production of autoantibodies against oxLDL was reduced during the treatment, indicating a lower level of the atherogenic antigen.

Comparison of advanced glycation endproducts on haemoglobin (Hb-AGE) and haemoglobin A1c for the assessment of diabetic control.

Glycation process in vivo results in two different products: early and advanced glycation endproducts (AGEs). The mechanism of early product formation has been well described, with HbA1c as the best-studied example. The finding that advanced glycation endproducts are also formed on haemoglobin suggests that HbA1c is a precursor for Hb-AGE formation. HbA1c has been well established as an important indicator for glycaemia monitoring, but the diagnostic role of Hb-AGE has not yet been clarified. A question is whether HbA1c and Hb-AGE are competitive or complementary parameters. In our study, Hb-AGE was quantified by the competitive ELISA technique using polyclonal anti-AGE-RNase antibodies to detect AGE immunoreactivities of proteins precipitated in red cell hemolysate. Results are expressed as AGE units/mg Hb. Hb-AGE was analysed in three groups of patients divided according to HbA1c values as follows: group I (n = 25) HbA1c < 7%, Hb-AGE = 6.93 (5.7-7.3) U/mg; group II (n = 25) HbA1c = 7-10%, Hb-AGE = 8.62 (7.7-10.2) U/mg; and group III (n = 25) HbA1c > 10%, Hb-AGE = 12.47 (10.8-13.9) U/mg (median (interquartile range)). A close relation between the amounts of red cell HbA1c and Hb-AGE was observed in all diabetic subjects (n = 75) r = 0.77, P < 0.001. Patients with HbA1c level > 8% were considered to be in poor glycaemic control and those with HbA1c < 8% in good control. In the well-controlled subgroup (n = 33), HbA1c and Hb-AGE were less tightly correlated (r = 0.37, P <0.001). However, in those patients with a higher level of HbA1c = 12.55 (8.9-13.3)% (n = 42), the related Hb-AGE was 11.5 (10.3-12.8) U/mg Hb, yielding a more significant correlation (r = 0.51, P < 0.001). The content of Hb-AGE did not correlate with age (r = 0.09), diabetes duration (r = 0.05) or severity of retinopathy and/or nephropathy. The observed difference may reflect a different kinetic rate of HbA1c production and subsequently the rate of Hb-AGE formation. The discrepancy in the correlation between HbA1c and Hb-AGE suggests that they are complementary rather than opposed parameters. The amount of haemoglobin-linked AGEs does not correlate with the presence or absence of retinopathy and/or nephropathy. It seems that Hb-AGE represents only the metabolic status, equally in the subjects with and without diabetic microangiopathy.

Temporal association between lens protein glycation and cataract development in diabetic rats.

In an attempt to shed more light on the relation between the glycation process and structural protein alterations, we followed the formation of glycated products in the lenses of hyperglycaemic Wistar rats during a period of 5 months following alloxan diabetes inducement. The study groups included non-diabetic (control), untreated diabetic rats (D), and diabetic rats receiving insulin alone or in combination with phlorizin, an inhibitor of renal tubular glucose transport. Lenses were removed at 4 and 20 weeks, and advanced glycation products in alkalisoluble lens proteins were determined by their characteristic spectrofluorescence (emission at 385 nm with excitation of 335 nm). In 20-week untreated diabetic rats as compared to control rats, a significant increase was observed in the fluorescence level (3.25 +/- 1.02 vs 1.61 +/- 0.17 FU/mg, p < 0.001), while in 4-week animals the increase was from 1.26 +/- 0.11 FU/mg in controls to 1.80 +/- 0.25 FU/mg in diabetics (P < 0.001). Daily treatment of 20-week diabetic rats with insulin alone (2.46 +/- 0.48 FU/mg) or in combination with phlorizin (2.30 +/- 0.26 FU/mg) did not significantly influence lens fluorescence level. The amount of glucosebound ketoamine linkage was estimated after acid hydrolysis as released 5-hydroxymethylfurfural (HMF). In 20-week controls, it was slightly higher than in 4-week controls (0.57 +/- 0.31 vs 0.41 +/- 0.20 nmol HMF/mg, respectively). The diabetic group showed a significant increase, however. In 4-week diabetics, a level of 1.07 +/- 0.36 nmol HMF/mg was found, while in 20-week animals the glycated protein amount rose to 2.46 +/- 0.79 nmol HMF/mg. In addition to the increases in glycated content with continuing diabetic hyperglycaemia, significant changes in protein composition of alkali-soluble lenses developed. The SDS-PAGE pattern showed an appearance of protein polymers of heterogeneous size (C 4 weeks 3.0 +/- 1.1% vs C 20 weeks 17.9 +/- 2.9%, D 4 weeks 7.3 +/- 2.1% vs D 20 weeks 19.8 +/- 3.6%) and the proteins of high molecular weight (HMW) failed to penetrate into the gel. Only a small amount of these HMW proteins was present in controls (C 20 weeks 2.5 +/- 1.2%) and short-term diabetes (D 4 weeks 0.8 +/- 0.2%), whereas in long-term untreated diabetes there was a dramatic increase (D 20 weeks 30.5 +/- 3.2%) with a corresponding decrease in other peaks. All diabetic animals from this group had macroscopically detectable cataractous lenses. Treatment with insulin or insulin/phlorizin followed the HMW protein level of the untreated animals (28.2 +/- 4.0% or 27.08 +/- 3.3% vs 30.52 +/- 3.32%).

Serum selenium values in healthy children aged 1-18 years in NE Slovenia.

OBJECTIVE: The objective of the paper was to establish the serum Se status in healthy children in the north-eastern region of Slovenia. SUBJECTS: In 71 healthy children of the age group 1-18 years the serum Se values were determined by means of atomic spectrometry. RESULTS: The results obtained show that the serum Se values depend on the age of the children. Thus the serum Se level in the youngest age group (1-2 years) was 74.9 +/- 9.7 micrograms/l; in the pre-school age group (3-5 years) it was 85.5 +/- 10.0 micrograms/l; and in the group of school children (11-13 years) it was 93.9 +/- 9.3 micrograms/l. The difference between the serum Se values in the youngest age group and all the other groups was statistically significant (P < 0.05). CONCLUSIONS: The serum Se levels rise gradually so that by the time the children reach school age their serum Se levels equal those found in healthy adult persons in Italy and several Western European countries, e.g. The Netherlands.