Serum Uromodulin in Children and Adolescents with Type 1 Diabetes Mellitus and Controls: Its Potential Role in Kidney Health.

INTRODUCTION: Uromodulin is a kidney-specific tubular protein, and its assessment in serum (sUMOD) reveals the potential as a novel marker for function and the integrity of renal parenchymal cells and does not directly depend on the glomerular filtration rate. Early diabetic nephropathy parallels glomerular hyperfiltration, often leading to diagnostic misinterpretation. Moreover, traditional kidney function markers are not able to diagnose structural lesions. Recent data show that sUMOD is linked to glucose intolerance in adults. Thus, we launched to assess the hypothesis that sUMOD is also associated with kidney function, biometric data, and quality of metabolic control in children/adolescents with type 1 diabetes. PATIENTS AND METHODS: Patients with type 1 diabetes (n=135) and healthy controls (n=69) were recruited to participate in the trial. Clinical, biometrical data, sUMOD, and other laboratory parameters were assessed. RESULTS: The mean concentrations of sUMOD in diabetic patients and controls were comparable (201.19±103.22 vs. 198.32±84.27 ng/mL, p=0.832). However, in contrast to healthy controls, sUMOD levels in patients with diabetes were associated with serum-creatinine (r=-0.368, p<0.0001), age (r=-0.350, p<0.0001), height (r=-0.379, p<0.0001), body weight (r=-0.394, p<0.0001), Body mass index (r=-0.292, p=0.001), daily insulin dosage (r=-0.300, p<0.0001), HbA1c (%) (r=-0.190, p=0.027), standardized HbA1c/IFCC (mmol/mol) (r=-0.189, p=0.028), and systolic (r=-0.299, p<0.0001) and diastolic (r=-0.235, p=0.006) arterial blood pressure. CONCLUSIONS: Our study shows that children/adolescents with type 1 diabetes disclose similar sUMOD concentrations as healthy controls. Serum UMOD appears to indicate higher risks for kidney tissue remodeling and possibly subsequent cardiovascular alterations. However, further studies are mandatory to settle these findings.

Advanced glycation end products and ß(2)-microglobulin as predictors of carpal tunnel syndrome in hemodialysis patients.

BACKGROUND/AIMS: Carpal tunnel syndrome (CTS) is a common clinical presentation of dialysis-related amyloidosis. It was determined whether ß(2)-microglobulin (ß2M) and advanced glycation end products in serum are predictors of CTS in dialysis patients. METHODS: A total of 385 hemodialysis patients were screened for CTS. ß2M in serum was determined by a competitive enzyme-linked immunoassay, CML by a competitive enzyme-linked immunosorbent assay and total pentosidine by reverse-phase high-performance liquid chromatography. RESULTS: 127 patients (33%) were treated with biocompatible membranes, 174 (45%) with high-flux dialysis. 122 patients (31.7%) had clinical signs of CTS. Significant predictors of CTS were: age, female gender, serum ß2M, total protein, dialysis with non-biocompatible high-flux dialysis compared to non-biocompatible low-flux dialysis, Kt/V and serum concentration of CML (OR 2.47 for the 3rd vs. 1st quartile, 95% CI 1.229-4.961, p = 0.011). CONCLUSION: The prevalence of CTS as a possible manifestation of dialysis-related amyloidosis is still high. Serum concentration of CML may be a predictor of CTS besides ß2M and malnutrition.

Vitamin B6 metabolism in chronic kidney disease--relation to transsulfuration, advanced glycation and cardiovascular disease.

BACKGROUND: Vitamin deficiency is common in chronic kidney disease (CKD). Data on B(6) supply and possible relationships to cardiovascular events (CVE) in CKD are rare. Pyridoxamine exerts inhibitory effects on the formation of advanced glycation endproducts (AGE) implicated in the pathogenesis of CKD and atherosclerosis. METHODS: In 48 CKD patients at stage 2-4, 72 hemodialysis patients (HD), 38 renal transplant recipients (RTR) and 141 healthy controls (mean age 58 +/- 13, 61 +/- 12, 50 +/- 12 and 54 +/- 16 years, respectively), plasma and red blood cell (RBC) concentrations of pyridoxal-5'-phosphate (PLP), pyridoxal (PL), 4-pyridoxic acid (PA), pyridoxamine-5'-phosphate (PMP) and of the AGE pentosidine were measured by high-performance liquid chromatography, N(epsilon)-(carboxymethyl)lysine and imidazolone by an ELISA, and total homocysteine and cystathionine by gas chromatography-mass spectrometry. RESULTS: Despite routine low-dose vitamin supplementation in HD, plasma PLP was decreased in HD (79 +/- 69 nmol/l) compared with CKD stage 2-4 patients (497 +/- 944 nmol/l), RTR (416 +/- 604 nmol/l) and controls (159 +/- 230 nmol/l; p < 0.001). Plasma PA was significantly increased in HD (11,667 +/- 17,871 nmol/l) in comparison with CKD stage 2-4 (435 +/- 441 nmol/l), RTR (583 +/- 668 nmol/l) and controls (46 +/- 49 nmol/l; p < 0.001). B(6) forms were significantly affected by renal function (R = 0.792, p < 0.001 for CKD stage 2-4). There was no relation of vitamers with a history of CVE. Relationships between B(6) forms and AGE (RBC-PMP with pentosidine in CKD stage 2-4: R = -0.351, p < 0.05) were found. CONCLUSION: HD patients showed a deficiency in PLP in plasma but not in RBC. Prospective trials are needed to elucidate the potential role of elevated PA on cardiovascular and renal outcome in CKD. Vitamin B(6) supplementation might be successful in preventing AGE-related pathologies.

Serum levels of the advanced glycation end products Nepsilon-carboxymethyllysine and pentosidine are not influenced by treatment with the angiotensin receptor II type 1 blocker irbesartan in patients with type 2 diabetic nephropathy and hypertension.

BACKGROUND/AIMS: The aim of this post-hoc analysis of a prospective study in patients with type 2 diabetic nephropathy was to investigate whether treatment with the angiotensin II type 1 receptor blocker irbesartan leads to a reduction in the serum levels of the advanced glycation end products (AGEs) pentosidine and N(epsilon)-carboxymethyllysine (CML). METHODS: One hundred and ninety-six patients of the Irbesartan in Diabetic Nephropathy Trial cohort (mean age 61 +/- 6.5 years, 62 female, 134 male) with a mean estimated glomerular filtration rate of 47.7 ml/min were treated with irbesartan (n = 65), the calcium channel blocker amlodipine (n = 61) or by placebo (n = 70). Serum levels of pentosidine and CML were measured at baseline and after follow-up (23.4 months). RESULTS: Estimated glomerular filtration rate decreased in all groups by a mean of 8.6 ml/min. Serum levels of AGEs increased significantly (p < 0.001) during follow-up. After controlling for renal function and total protein concentration, changes were 53, 55, 50% for pentosidine and 29, 24, 23% for CML (irbesartan, amlodipine and placebo group, respectively). The increase was not significantly different between the treatment groups. CONCLUSION: Irbesartan did not alter the increase in pentosidine and CML in serum of type 2 diabetic patients with progressive nephropathy. This finding suggests that angiotensin receptor blockade alone is insufficient to reduce serum levels of AGEs in diabetic nephropathy.

Long-term treatment of obese children and adolescents using a telemedicine support programme.

A total of 140 obese patients (mean age 14 years) participated in a structured treatment and teaching programme (STTP) in hospital, with the aim of weight reduction. At both the start and finish of the STTP, patients underwent clinical and psychological examination. During an average hospital stay of 35 days, their mean bodyweight decreased from 82.4 kg to 76.0 kg (P < 0.001). Patients were then followed up with a telemedicine support programme. During the next 12 months, the acceptance of the telemedicine support programme declined from 93% to 46%. The body mass index was 30.5 kg/m(2) at admission and 27.7 kg/m(2) at 12-month follow-up (P < 0.05). In parallel, wellbeing and treatment satisfaction increased, and there was a positive effect on eating behaviour and exercise. Intervention was needed in up to 64% of the children and adolescents who participated in the programme, most frequently due to poor results in exercise. Telemedical follow-up care and counselling seemed to be highly effective, and allowed not only an initial weight reduction, but long-term stabilization as well.

[Quality of Blood Pressure Control in General Practice Using Ambulatory Blood Pressure Monitoring - a Retrospective Monocentric Cross-Sectional Study]. / Qualität der Blutdruckeinstellung in der hausärztlichen Praxis unter Verwendung der 24-Stunden-Langzeitblutdruckmessung ­ eine retrospektive monozentrische Querschnittsstudie.

INTRODUCTION: The diagnosis and therapy of arterial hypertension is a continuous challenge in general practice. The aim of this study is to analyze the nature and effectiveness of blood pressure control in patients with known arterial hypertension in a primary care practice using office- (OBPM) and ambulatory (ABPM) blood pressure measurement. METHODS: 283 patients (90 % of all regularly treated patients having hypertension) were retrospectively examined for the achievement of the target blood pressure values in ABPM and OBPM in the past 1 to 2 years. Target blood pressure levels were in line with current ESH recommendations (office blood pressure < 140/90 mmHg, mean 24-h ABPM < 130/80 mmHg). RESULTS: The OBPM of all patients (age: 68 ±â€Š12.7, 48 % women) was 132 ±â€Š11.8/80 ±â€Š4.2 mmHg, the 24-h ABPM was 128 ±â€Š10.7/74 ±â€Š7.9 mmHg. An isolated office hypertension had 11.3 %, a masked hypertension 21.9 %. Only 33.9 % had physiological dipping behavior (49.1 % non-dipper, 13.8 % reverse dipper and 3.2 % extreme dipper). The blood pressure control rate (reaching the target blood pressure) was 67.8 % in the OBPM and 57.2 % in the 24-h ABPM. 23.0 % were treated with monotherapy, 37.5 % with dual combination, 19.8 % with a triple combination and 14.5 % with > 3 antihypertensives. 83.9 % of all had RAS blockers. The OBPM target was achieved in 75.0 % under a triple and 71.7 % under dual combination. The 24-hour ABPM target was mostly achieved in patients requiring only monotherapy (66.2 %) or dual therapy (60.4 %); others < 60 %. CONCLUSION: In the family practice examined, the treatment control of patients with arterial hypertension was mostly guideline-based and better than described in the literature. The parallel and consistent implementation of ABPM in addition to OBPM as well as the high prescription rate of RAS blockers and recommended combination therapies might be the key for this result.

Analysis of glycoproteins in human serum by means of glycospecific magnetic bead separation and LC-MALDI-TOF/TOF analysis with automated glycopeptide detection.

Comprehensive proteomic analyses require efficient and selective pre-fractionation to facilitate analysis of post-translationally modified peptides and proteins, and automated analysis workflows enabling the detection, identification, and structural characterization of the corresponding peptide modifications. Human serum contains a high number of glycoproteins, comprising several orders of magnitude in concentration. Thereby, isolation and subsequent identification of low-abundant glycoproteins from serum is a challenging task. selective capturing of glycopeptides and -proteins was attained by means of magnetic particles specifically functionalized with lectins or boronic acids that bind to various structural motifs. Human serum was incubated with differentially functionalized magnetic micro-particles (lectins or boronic acids), and isolated proteins were digested with trypsin. Subsequently, the resulting complex mixture of peptides and glycopeptides was subjected to LC-MALDI analysis and database searching. In parallel, a second magnetic bead capturing was performed on the peptide level to separate and analyze by LC-MALDI intact glycopeptides, both peptide sequence and glycan structure. Detection of glycopeptides was achieved by means of a software algorithm that allows extraction and characterization of potential glycopeptide candidates from large LC-MALDI-MS/MS data sets, based on N-glycopeptide-specific fragmentation patterns and characteristic fragment mass peaks, respectively. By means of fast and simple glycospecific capturing applied in conjunction with extensive LC-MALDI-MS/MS analysis and novel data analysis tools, a high number of low-abundant proteins were identified, comprising known or predicted glycosylation sites. According to the specific binding preferences of the different types of beads, complementary results were obtained from the experiments using either magnetic ConA-, LCA-, WGA-, and boronic acid beads, respectively.

Increased binding of beta-2-microglobulin to blood cells in dialysis patients treated with high-flux dialyzers compared with low-flux membranes contributed to reduced beta-2-microglobulin concentrations. Results of a cross-over study.

BACKGROUND: Patients on long-term dialysis eventually develop amyloid deposits with beta2-microglobulin as a predominant component. Although several studies have suggested that high-flux membranes reduce beta2-microglobulin in plasma compared with low-flux dialyzers, the mechanisms underlying this observation are still discussed. METHODS: We revisited this important subject and measured beta2-microglobulin in the plasma of healthy individuals (n = 8), and patients undergoing hemodialysis (n = 20) who for assigned periods of time were either treated with a low-flux membrane (cuprophan) or high-flux (polyamide) dialyzer with an ELISA. The number of blood cells was determined by FACS. Beta2-microglobulin was also measured on the surface of granulocytes, lymphocytes, and monocytes before, directly after, and 4 h after hemodialysis. Expression of beta2-microglobulin, c-fos, tumor necrosis factor-alpha (TNF-alpha), and interleukin-1 mRNA was determined in whole blood samples with quantitative RT-PCR using an internal standard in parallel. In the second part of the study, patients were assigned in a two-group cross-over design either to low- or high-flux dialyzers (n = 9 in each group), and dialyzer membranes were changed every 4 weeks for two consecutive periods. Serum beta2-microglobulin concentrations were measured at the end of each period. RESULTS: Healthy controls had a low plasma beta2-microglobulin level of 1.2 +/- 0.3 mg/l. Before hemodialysis, patients on low-flux dialyzers had a plasma beta2-microglobulin level of 42.0 +/- 14.0 mg/l, patients treated with high-flux dialyzers 21.5 +/- 10.8 mg/l (p < 0.05 vs. low-flux dialyzers). In contrast, there was no significant difference in plasma concentrations of active transforming growth factor-beta1 with the two different membrane types. The difference in serum beta2-microglobulin between low- and high-flux membranes was more prominent directly after hemodialysis as well as 4 h after hemodialysis compared with the values directly before the start of treatment. At all studied time-points, leukocytes and platelets were significantly higher in patients on low-flux membranes. Healthy control persons exhibited a significantly higher amount of beta2-microglobulin bound to granulocytes, lymphocytes, and monocytes compared with dialysis patients. Interestingly, beta2-microglobulin bound to granulocytes, lymphocytes, and monocytes was significantly increased in patients treated with high-flux membranes compared with low-flux filters. Quantitative RT-PCR revealed no significant difference in beta2-microglobulin expression in whole blood before hemodialysis, directly after hemodialysis, and 4 h after hemodialysis. However, TNF-alpha and c-fos transcripts were significantly higher in whole blood obtained from patients treated with low-flux membranes compared to high-flux dialyzers. The two-group cross-over study over three periods of 4 weeks revealed that switching from low-flux to high-flux dialyzers significantly reduced serum beta2-microglobulin levels. CONCLUSION: Patients treated with a polyamide high-flux membrane had lower beta2-microglobulin concentrations compared with those patients on low-flux dialyzers. This difference might not be mediated by an increase in beta2-microglobulin mRNA, but may be caused by less beta2-microglobulin released from the blood cells in patients treated with high-flux dialyzers, in addition to a better beta2-microglobulin clearance.

Trends in the management of arterial hypertension in patients with type 1 and insulin-treated type 2 diabetes mellitus over a period of 10 years (1989/1990-1994/1995). Results of the JEVIN trial.

UNLABELLED: For populations of patients with insulin-treated diabetes mellitus, information about the quality of blood pressure control, an independent risk factor for cardiovascular mortality and morbidity, is widely lacking. Hence, it was the goal of the trial to evaluate the prevalence of arterial hypertension, the quality of blood pressure control and changes in treatment modalities over a period of 10 years. PATIENTS AND METHODS: In 1989/1990, Jena's St. Vincent (JEVIN) Trial started as a prospective, population-based survey with 10-year follow-up of all patients with type 1 and insulin-treated type 2 diabetes mellitus aged 16 to 60 years and living in the city of Jena, Thuringia, Germany. RESULTS: In 1999/2000, 46 (40.4%) of 114 patients with type 1 and 104 (70.7%) of 147 patients with insulin-treated type 2 diabetes were on blood pressure-lowering drugs. Hypertension prevalence in the total population was 57.5%. It was higher in patients with insulin-treated type 2 than in type 1 diabetes (47.4% vs. 78.9%, P<.001). In 1999/2000, the number of patients with type 1, but also type 2, diabetes on blood pressure-lowering agents was higher than in 1994/1995 and 1989/1990. In the whole group, the mean blood pressure improved from 1989/1990 up to 1994/1995 and has remained constant up to the follow-up examination in 1999/2000. In 1999/2000, of those with arterial hypertension, blood pressure was higher than the 140/90-mm Hg target in 17.5% (20/114) of the patients with type 1 and in 42.2% (62/147) of the patients with insulin-treated type 2 diabetes. CONCLUSIONS: The JEVIN trial provides a useful population-based summary of the quality of blood pressure and metabolic control of patients with insulin-treated diabetes. Although the trial demonstrates an impressive improvement in the quality of blood pressure and metabolic control over the last decade, it also shows various problems: In many patients, both with type 1 and type 2 diabetes mellitus, a good blood pressure control (below 140/90 mm Hg) has not been achieved. Moreover, drug therapy, in particular concerning patients with overt nephropathy, is often inappropriate.

Suitability of 5/6 nephrectomy (5/6NX) for the induction of interstitial renal fibrosis in rats--influence of sex, strain, and surgical procedure.

Chronic renal failure (CRF) is a serious clinical problem and currently there are no adequate therapeutic strategies for treatment. Many possible treatment strategies have been tested in rats with CRF induced by subtotal nephrectomy. However, reports in the literature concerning the consequences of this procedure on rat kidney function are contradictory. For instance, such an intervention in male Sprague-Dawley rats apparently initiates the development of interstitial renal fibrosis, while in our similar studies on female Wistar rats (HW) there was minimal renal fibrosis. Therefore, we carried out experiments in adult rats to investigate the long-term consequences of 5/6 nephrectomy (5/6NX) in relation to (1) sex, (2) strain, and (3) two methods of surgical ablation. Ten weeks after 5/6NX, body weight gain, systolic blood pressure, creatinine clearance, and urinary protein were measured, along with renal hydroxyproline concentration determinations to assess the deposition of extracellular matrix. Also, light microscopic investigations were done to characterize renal damage. The functional parameters clearly indicated the development of CRF, while morphologic investigations showed only moderate fibrotic areas containing atrophic tubules and lymphocytic infiltrates. However, 45-60% of glomeruli were sclerotic. In summary, 5/6NX, using either method of partial nephrectomy, induces signs of moderate glomerulonephritis preferentially in female HW rats. Thus 5/6NX in female HW rats can be recommended as a suitable model in the induction of renal fibrosis.

Plasma copeptin in children and adolescents with type 1 diabetes mellitus in comparison to healthy controls.

UNLABELLED: In a cohort of children and adolescents with type 1 diabetes mellitus the trial tested the hypothesis that copeptin levels are associated with kidney function, biometrical data and quality of diabetes control. PATIENTS AND METHODS: A total of 141 subjects were recruited to participate in the trial: 80 patients with type 1 diabetes (13.0±3.4years, HbA1c 7.85±1.42%) and 61 healthy controls (12.4±2.8years). Clinical and socio-economic data were assessed. A sandwich immunoassay (B.R.A.H.M.S. GmbH/Thermo Fisher Scientific, Hennigsdorf/Berlin, Germany) was used for measuring plasma copeptin levels. RESULTS: The mean concentration of copeptin in the diabetic patients was 4.75±3.46pmol/l. There was a strong inverse correlation between copeptin and GFR (r=-0.86, p=0.021), as well as with total cholesterol (r=-0.23, p=0.041), LDL-cholesterol (r=-0.24, p=0.036), but not with serum creatinine, albuminuria, HbA1c, blood glucose, MAGE, CRP, systolic or diastolic blood pressure or age, diabetes duration, weight, height and BMI. Comparing patients with a diabetes duration of ⩾7years (n=45) with those with a diabetes duration <7years (n=35), patients with a longer duration of diabetes had higher copeptin levels (5.24±2.26 vs 4.13±2.86, p=0.045). Performing multivariate analyses only GFR could be identified as a parameter associated with copeptin (R-square=0.05, ß=-0.23, p=0.032). In the healthy controls mean copeptin concentration was 5.56±3.15pmol/l. The copeptin concentration and GFR were inversely correlated as well (r=-0.61, p=0.034). However, other correlation and multivariate analyses revealed no further significant results. Comparing patients with type 1 diabetes mellitus with the healthy controls, the diabetes patients revealed no significant difference with respect to copeptin (p=0.24), serum creatinine (49.8±11.9 vs 50.4±11.0µmol/l, p=0.53) or GFR (102.4±23.3 vs 104.5±19.1ml/min, p=0.47). On the other hand, patients with type 1 diabetes had lower concentrations of CRP (1.66±3.91 vs 3.21±3.04µg/ml, p=0,013), triglycerides (0.88±0.53 vs 1.13±0.60mmol/l, p=0.010), and a lower ratio of LDL-/HLD-cholesterol (1.73±0.69 vs 2.32±0.80, p<0.001), as well as lower body weight (51.3±18.0 vs 60.3±15.7kg, p=0.002) and BMI (19.7±3.8 vs 23.2±2.9kg/m(2), p<0.001). In contrast to the controls, the diabetes patients had higher blood glucose levels at the time of examination (8.2±3.8 vs 4.7±0.5mmol/l, p<0.001), higher HDL-cholesterol levels (1.59±0.34 vs 1.26±0.24mmol/l, p<0.001), as well as higher education and higher educational levels of the mothers. CONCLUSIONS: The present trial revealed a clear association between GFR and copeptin in children and adolescents with type 1 diabetes mellitus. Hence, copeptin can be considered as a marker of renal function.

Identification of Predictors for Weight Reduction in Children and Adolescents with Overweight and Obesity (IDA-Insel Survey).

INTRODUCTION: Worldwide, overweight and obesity are known as posing serious health risks. Successful methods of prevention and therapy for overweight and obesity have remained elusive. It was the aim of the present trial to identify parameters and determinants to guarantee long-term weight reduction. PATIENTS AND METHODS: In total 143/159 children and adolescents (90%) with overweight and obesity completed the prospective, multicenter trial (age 13.9 ± 2.4 years, BMI 31.2 ± 5.4 kg/m², BMI-SDS 2.51 ± 0.57). During a six-week rehabilitation patients participated in a structured treatment and teaching program (STTP). Following the inpatient treatment the children and adolescents were monitored over a period of 24 months (physical examination, measurements of BMI, BMI-SDS, body composition, carotid intima-media thickness, laboratory parameters, blood pressure, and standardized questionnaires to assess socio-demographic, socio-economic parameters, eating behavior, well-being, quality of life, intelligence, intrafamilial conflicts, self-efficacy, resilience, sense of coherence, stress-management, social support, and actual body shape). RESULTS: 66% of the children and adolescents showed non-normal laboratory parameters as well as higher blood pressure and/or an increased carotid intima-media thickness. Mean thickness of carotid intima-media was 0.53 ± 0.09 mm (range, 0.40-0.80); 15% of the patients showed a normal range (<0.45 mm), 40% slightly elevated (0.45-0.50 mm) and 45% an elevated (>0.50 mm) thickness. After an inpatient treatment lasting 40.4 ± 4.1 (range, 28-49) days, children and adolescents reached a mean weight reduction of 5.52 ± 3.94 (0.4-13.3) kg (p < 0.01) accompanied by a reduction of body fat mass. Performing multivariate analyses, the most important psychological factors associated with long-term weight reduction were identified (R-square = 0.53): Well-being (ß = -0.543), resilience (ß = 0.434) and intrafamilial conflicts (ß = 0.315). CONCLUSION: The different parameters (i.e., resilience, intrafamilial conflicts, structured daily schedule) have demonstrated their utility and strategies should be developed allowing an adaption of these into the STTPs and the integration of intervention into the therapeutic setting.

Predictors and determinants for weight reduction in overweight and obese children and adolescents.

INTRODUCTION: Worldwide, overweight and obesity are known as posing serious health risks. Successful methods for weight reduction have remained elusive. This multicenter non-randomised trial aimed to identify parameters and determinants of long-term weight reduction. PATIENTS AND METHODS: A total of 143/159 overweight and obese children and adolescents (90 %) completed the prospective multicenter trial (age 13.9±2.4 years, BMI 31.2±5.4kg/m2, BMI-SDS 2.51±0.57). During a 6-week rehabilitation period the patients participated in a structured treatment and teaching program (STTP). Following in-patient treatment the children and adolescents were monitored over a period of 24 months (physical examination, measurements of BMI, BMI-SDS, body composition, carotid intima-media thickness, laboratory parameters, blood pressure, standardized questionnaires to assess socio-demographic and socio-economic parameters, eating behavior, well-being, quality of life, intelligence, intrafamilial conflicts, self-efficacy, resilience, sense of coherence, stress management, social support, actual body shape). RESULTS: 66% of the children and adolescents had abnormal laboratory parameters as well as higher blood pressure and/or an increased carotid intima-media thickness. The mean carotid intima-media thickness was 0.53±0.09mm (range 0.40 to 0.80); 15% of the patients showed normal range values (< 0.45mm), 40% a slightly elevated (≥ 0.45 to ≤ 0.50mm) and 45% an elevated (> 0.50mm) thickness. After the inpatient treatment lasting 40.4±4.1 (range 28 to 49) days, children and adolescents reached a mean weight reduction of 5.52±3.94 (0.4 to 13.3) kg (p<0.01) that was accompanied by a reduction in body fat mass. Using multivariate analyses, the most important psychological factors associated with long-term weight reduction were identified (R-square=0.53): well-being (ß=-0.543), resilience (ß=0.434), and sense of coherence (ß=0.315). CONCLUSION: The different parameters (i. e., well-being, resilience, sense of coherence) have demonstrated their utility, and strategies should be developed allowing an adaption of these into the STTPs.

Advanced glycation end products: a possible link to angiotensin in an animal model.

Advanced glycation end products (AGEs) have been associated with progressive vascular and renal damage in a variety of pathological conditions such as renal failure and diabetes mellitus. The formation of AGEs is generally attributed to increased oxidative and carbonyl stress or hyperglycemia. Activation of the cellular receptor of AGE (RAGE) leads to subsequent cellular activation and proinflammatory responses. Angiotensin (Ang) produces cellular oxidative stress and similarly promotes end organ damage via its type 1 receptor. We investigated the interrelation between these two systems in a new transgenic rat (TGR) model with Ang II-dependent hypertension and renal damage and in nontransgenic controls. TGR showed increased systolic blood pressure (approximately 210 mmHg), proteinuria, and increased renal collagen I mRNA expression compared with normotensive nontransgenic controls. Immunohistochemical staining of kidney sections showed colocalization for Nepsilon-carboxy(methyl)lysine, RAGE, and NF-kappaB in TGR glomeruli. These features were absent in nontransgenic controls. Our observations suggest a possible link between Ang II-dependent end-organ damage and the AGE/RAGE axis in vivo. TGRs provide an excellent model to study the interrelation between the renin-angiotensin system and the AGE/RAGE axis in promoting cardiovascular end-organ damage, which would otherwise not be possible in humans.

[Costs of therapy of insulin-treated patients with Diabetes mellitus in Germany. Results of the JEVIN trial]. / Therapiekosten bei insulinbehandelten Patienten mit Diabetes mellitus in Deutschland am Beispiel der JEVIN-Studie.

BACKGROUND AND PURPOSE: Diabetes mellitus, its treatment with oral antidiabetic drugs and insulin, self-monitoring and the development of diabetesrelated long-term complications raise multiple socioeconomic problems. Hence, diabetes is one of the major challenges to modern health care systems. To date, there are only few data analyzing diabetes-related costs. Therefore, it was the aim of this trial to assess the costs of therapy of insulin-treated patients with diabetes mellitus out of a selection-free population over a period of 5 years. PATIENTS AND METHODS: JEVIN (Jena's St. Vincent trial) is a prospective population-based trial of all patients with type 1 and insulin-treated type 2 diabetes mellitus aged 16-60 years and living in the city of Jena, Thuringia, Germany. In addition to parameters of diabetes control (relative hemoglobin A(1c) [= HbA(1c)/mean normal], long-term complications, blood pressure), the costs of therapy in respect of insulin and oral antidiabetic drugs and materials to perform self-monitoring were analyzed in 1999/2000 compared to 1994/95. In 1994/95, 244 patients, in 1999/2000, 291 patients were examined. RESULTS: During the period from 1994/95 to 1999/2000, relative HbA(1c) improved in both patients with type 1 (1.65 +/- 0.35 [n = 127] vs 1.48 +/- 0.30 [n = 114]; p < 0.0001) and insulin-treated type 2 diabetes (1.75 +/- 0.40 [n = 117] vs. 1.47 +/- 0.25 [n = 147]; p < 0.0001). The quality of blood pressure control remained constant. In 1999/2000 the costs per unit insulin for patients with type 1 diabetes were calculated at about 0.078 +/- 0.035 DM, in 1994/95 at 0.075 +/- 0.032 DM (p = 0.873). For patients with type 2 diabetes the costs were calculated at 0.070 +/- 0.032 DM in 1999/2000 and at 0.070 +/- 0.028 DM (p = 0.954) in 1994/95. In 1999/2000, to perform blood glucose self-monitoring the costs were 4.08 +/- 1.39 DM/d for patients with type 1 diabetes and 3.07 +/- 1.36 DM/d for patients with type 2 diabetes. In 1994/95 the costs for patients with type 1 diabetes amounted to 3.56 +/- 1.69 DM/d (p = 0.012), and for patients with insulin-treated type 2 diabetes mellitus to 2.77 +/- 1.66 DM/d (p = 0.138). In 1999/2000 the costs for antihypertensive drugs in 46/114 patients with type 1 diabetes were calculated at about 1.43 +/- 1.10 DM/d. In 1994/95 the costs for 32/127 patients amounted to 1.76 +/- 1.00 DM/d (p = 0.501). For 104/147 patients with insulin-treated type 2 diabetes, the costs of antihypertensive drugs were 2.02 +/- 1.48 DM/d in 1999/2000. In 1994/95 the costs amounted to 1.77 +/- 1.11 DM/d (p = 0.141) for 54/117 patients. In 1994/95 the total costs for patients with type 1 diabetes mellitus were calculated at about 7.10 +/- 2.69 DM/d. In 1999/2000 the costs amounted to 7.70 +/- 2.75 DM/d (p = 0.085). In patients with insulin-treated type 2 diabetes mellitus there was a significant increase in 1999/2000 versus 1994/95 (1994/95: 6.43 +/- 3.16, 1999/2000: 7.57 +/- 3.56 DM/d; p = 0.007). CONCLUSION: Despite a tendency toward an increase in the costs for daily life, the therapy-related costs for patients with type 1 diabetes mellitus were constant in 1999/2000 versus 1994/95. In patients with type 2 diabetes, there was an increase of about 18%. For both patients with type 1 and type 2 diabetes, the costs were substantially higher than calculated in theoretical models.

Methylglyoxal-derived hydroimidazolone advanced glycation end-products of human lens proteins.

PURPOSE: To determine the concentrations of methylglyoxal-derived advanced glycation end-products (AGEs), the hydroimidazolones MG-H1 and -H2, in soluble human lens proteins and compare them with the concentrations of other methylglyoxal-derived AGEs and pentosidine. METHODS: Lens protein samples were hydrolyzed enzymatically. AGEs were assayed without derivatization by HPLC with tandem mass spectrometry; the fluorescent AGEs argpyrimidine and pentosidine were assayed by fluorometric detection. MG-H1 and -H2 were resolved and assayed by fluorometric detection after derivatization with 6-aminoquinolyl-N-hydroxysuccimidylcarbamate (AQC). RESULTS: The methylglyoxal-derived hydroimidazolones MG-H1 and -H2 were detected and quantified in human lens proteins. AGE concentrations (mean +/- SEM) were: MG-H1 4609 +/- 411 pmol/mg protein, MG-H2 3085 +/- 328 pmol/mg protein, argpyrimidine 205 +/- 19 pmol/mg protein, and pentosidine 0.693 +/- 0.104 pmol/mg protein. The concentration of MG-H1 in human lens protein correlated positively with donor age (correlation coefficient = 0.28, P < 0.05), the concentration of MG-H2 (correlation coefficient = 0.78, P < 0.001) and argpyrimidine (correlation coefficient = 0.42, P < 0.01). The concentrations of AGEs were increased in cataractous lenses in comparison with noncataractous lenses: the increases were MG-H1 85%, MG-H2 122%, argpyrimidine 255%, and pentosidine 183% (P < 0.001). Multiple logistic regression analysis showed a significant link of cataract to donor age (regression coefficient beta = 0.094, P = 0.026) and argpyrimidine (beta = 0.022, P = 0.002). CONCLUSIONS: Methylglyoxal hydroimidazolones are quantitatively major AGEs of human lens proteins. These substantial modifications of lens proteins may stimulate further glycation, oxidation, and protein aggregation leading to the formation of cataract.

Are advanced glycation end products cardiovascular risk factors in patients with CRF?

BACKGROUND: Chronic renal failure (CRF) is characterized by enhanced formation and accumulation of advanced glycation end products (AGEs), which are involved in the pathogenesis of vascular damage. Their role as risk factors for cardiovascular complications is still unknown. This study aims to investigate whether elevated serum levels of the AGEs pentosidine, N(epsilon)-carboxymethyllysine (CML), and the 3-deoxyglucosone-derived imidazolone involve a greater risk for cardiovascular events (CVEs) and left ventricular hypertrophy (LVH). METHODS: Patients with CRF (n = 99), on maintenance hemodialysis (HD) therapy (n = 84), and renal transplant recipients (RTRs; n = 50) were included. Pentosidine was measured by high-performance liquid chromatography, and CML and imidazolone, by enzyme-linked immunosorbent assays. Statistical analyses were performed using Mann-Whitney U test, logistic regression analysis, and Cox proportional hazards model. RESULTS: At baseline in all investigated groups, patients with a history of CVEs or LVH showed greater mean serum AGE levels. By retrospective data analysis, significant odds ratios for increases in CML and imidazolone levels were calculated for LVH in HD patients, as well as for increases in CML levels for CVEs in RTRs, respectively. By prospective data analysis, serum AGE levels could not be evaluated as independent risk factors for CVEs in all investigated groups. CONCLUSION: From these preliminary results, serum AGE levels could not be identified as independent risk factors for CVEs or LVH in patients with CRF. Prospective studies are needed to answer this question.

Characterization of the postglomerular renal metabolism of lepirudin in healthy volunteers.

INTRODUCTION: The anticoagulant r-hirudin lepirudin is eliminated exclusively via the kidneys. We examined the C-terminal amino acid degradation of lepirudin by the proximal kidney tubulus cells in humans as well as the antithrombotic efficacy of the metabolites and quantified the metabolite portions. MATERIALS AND METHODS: In vitro metabolites of lepirudin were produced by adding 250 microg lepirudin to urine of three healthy volunteers and a concentration of 100 ml fresh urine to 1.5 ml and subsequent separation by high performance liquid chromatography. Anticoagulant activities of the mass spectrometrically identified metabolites were measured by ecarin clotting time and protein determination with bicinchoninic acid. In 10 healthy volunteers 1 mg lepirudin was administered intravenously, urine was collected during the following 2 h. The urine amount containing 50 microg lepirudin measured by ecarin clotting time was enzyme-inactivated and measured analogously to the in vitro samples. RESULTS: The in vitro generated metabolites were shortened amino acid by amino acid at the C-terminal end, up to five amino acids. Their anticoagulant activity was reduced to 92.6% (M64), 80.1% (M63) and 74.4% (M60,61,62) in comparison to lepirudin. Lepirudin (57.9 +/- 8.6%) was eliminated unchanged via the kidneys. Identical to the in vitro situation metabolite fragments were built in the distribution M64 = 8.1 +/- 5.7%, M63 = 21.1 +/- 6.5%, and M60,61,62 = 12.9 +/- 4.5%. CONCLUSIONS: Lepirudin is metabolized spontaneously in more than 10-fold concentrated urine. Metabolization of lepirudin takes place in the proximal tubulus cells as well. In vitro, the degradation takes place amino acid by amino acid, but in vivo even dipeptides and perhaps tripeptides are degraded.

Serum concentrations of asymmetric (ADMA) and symmetric (SDMA) dimethylarginine in patients with chronic kidney diseases.

BACKGROUND: NO synthesis is inhibited by the dimethylarginine (DMA) ADMA, which accumulates, similar to SDMA, in the plasma of patients suffering from chronic renal failure (CRF). ADMA and possibly SDMA contribute to hypertension and atherosclerosis in patients with chronic renal disease: ADMA inhibits directly eNOS, whereas SDMA competes with the NO precursor arginine for uptake into the cells. METHODS: In 26 control persons and 221 patients with kidney diseases of different stage as were CRF, end stage renal disease (ESRD), and patients after renal transplantation (RT), the plasma concentrations of ADMA (c(ADMA)), SDMA (c(SDMA)) and 20 endogenous amino acids (AA) were measured by HPLC and correlated to blood pressure, cardiac events, endothelial dysfunction, and diabetes mellitus. RESULTS: Both ADMA (1.04+/-0.04 vs. 0.66+/-0.04 microM) and SDMA (2.69+/-0.12 vs. 0.49+/-0.03 microM) were significantly (p<0.001) elevated in all patients compared to healthy controls, whereas arginine concentration (51.4+/-2.3 vs. 76.0+/-5.2 microM) was decreased in dependence on the degree of kidney disease. In RT patients, SDMA levels were significantly decreased, but c(ADMA) remained enhanced. A strong correlation was found between SDMA and both serum urea and creatinine in CRF and RT patients. A linear correlation was found between ADMA and cholesterol concentrations in RT patients. Hypertension in CRF was accompanied by a further increase in the concentration of DMAs. There was no relation between DMAs and the occurrence of peripheral arterial occlusive disease or cerebrovascular diseases. In patients with cardiac diseases, c(SDMA) was additionally increased only in the CRF group. CONCLUSIONS: In patients with chronic kidney disease, c(ADMA) and c(SDMA) are significantly increased but cardiovascular diseases are evidently not correlated to changes in DMA concentrations in this group of patients.