Effect of a weight loss program in obese adolescents; a long-term follow-up

OBJECTIVES

Obesity during adolescence is an increasing health problem in industrial countries. The co-morbidities associated with obesity include important metabolic diseases.

METHODS

To analyze the effect of a weight-loss program, we recruited 12 obese, male adolescents before entering this program. We determined body weight measures at baseline, 6-week and 36-month follow-up. Also, the long-term changes of blood pressure, HbA1c, and CRP were evaluated. Twenty healthy age-matched adolescents served as controls.

RESULTS

Within the intervention group ((body mass index [BMI, kg/m2] > 95th percentile for age and sex, age 13-17 years) the BMI and BMI-standard deviation score [SDS] were significantly reduced in the 6-week follow-up after completing the weight loss program. However, the significant weight-reduction effect was not persistent until the 36-month follow-up.

CONCLUSION

The 6-week weight-loss program had beneficial short-term effects on body weight, BMI, and BMI-SDS in obese adolescents, but these effects could not be maintained until the 36-month follow-up.

De novo expression of fetal ED-A(+) fibronectin and B (+) tenascin-C splicing variants in human cardiac allografts: potential impact for targeted therapy of rejection

Management of acute and especially chronic rejection after human cardiac transplantation is still challenging. Chronic rejection, represented by allograft vasculopathy (CAV) and cardiac interstitial fibrosis (CIF) is known to cause severe long-term complications. Rejection associated tissue-remodelling entails the reoccurrence of fetal variants of Fibronectin (Fn) and Tenascin-C (Tn-C), which are virtually absent in adult human organs. In a rat model, an extensive re-expression could be demonstrated for ED-A(+) Fn with spatial association to CAV and CIF. Thus, it is of great interest to investigate the cardiac tissue expression and distribution in human samples. From 48 heart transplanted patients, 64 tissue specimens derived from right ventricular biopsies were available. Histopathological analysis was performed according to the International Society for Heart and Lung Transplantation (ISHLT) guidelines for the detection of acute rejection. By immunohistochemistry, protein expression of ED-A(+) Fn, B(+) Tn-C, alpha-smooth muscle actin, CD31 and CD45 was assessed and analysed semiquantitatively. Co-localisation studies were performed by means of immunofluorescence double labelling. Histopathological analysis of the 64 samples revealed different ISHLT grades (0R in 36 cases, 1R in 20 cases and 2R in 8 cases). There was a distinct and quantitatively relevant re-occurrence of ED-A(+) Fn and B(+) Tn-C in most samples. Semi-quantitative evaluation did not show any correlation to the acute rejection grade for all markers. Interestingly, significant correlations to the extent of inflammation could be shown for ED-A(+) Fn (r = 0.442, p = 0.000) and B(+) Tn-C (r = 0.408, p = 0.001) as well as between both proteins (r = 0.663, p = 0.000). A spatial association of ED-A(+) Fn and B(+) Tn-C to CAV and CIF could be demonstrated. A relevant re-occurrence of ED-A(+) Fn and B(+) Tn-C following human heart transplantation could be demonstrated with spatial association to signs of rejection and a significant correlation to tissue inflammation. These data might contribute to the identification of novel biomarkers reflecting the rejection process and to the development of promising strategies to image, prevent or treat cardiac rejection.

Impact of ischemia-reperfusion on extracellular matrix processing and structure of the basement membrane of the heart

PURPOSE

Acute ischemic injury is a strong inductor of cardiac remodelling, resulting in structural changes of the extracellular matrix (ECM) and basement membrane (BM). In a large animal model of ischemia-reperfusion (I/R) we investigated the post-ischemic liberation of the collagen-IV-fragments Tumstatin (TUM; 28 kDa-fragment of collagen-IV-alpha-3), Arresten (ARR; 26 kDa-fragment of collagen-IV-alpha-1) and Endorepellin (LG3, 85 kDa-fragment of perlecan) which are biologically active in angiogenesis and vascularization in the post-ischemic myocardium.

METHODS AND RESULTS

In this blinded study, 30 pigs were randomized to 60 min of global I/R at either 4°C or 32°C or served as control. Three transmyocardial tissue samples were collected prior to ischemia and within 30 min and 150 min of reperfusion. Tissue content of TUM, ARR and LG3 was analyzed by western blotting and immunostaining. Within 150 min of mild hypothermic I/R a significantly increased tissue content of ARR (0.17±0.14 vs. 0.56±0.56; p = 0.001) and LG3 (1.13±0.34 vs. 2.51±1.71, p<0.001) was observed. In contrast, deep hypothermic I/R was not associated with a significant release of cleavage products. Cleavage of TUM remained unchanged irrespective of temperature. Increased matrix processing following mild hypothermia I/R is further supported by a >11fold elevation of creatine kinase (2075±2595 U/l vs. 23248±6551 U/l; p<0.001) in the coronary sinus plasma samples. Immunostaining demonstrated no changes for ARR and LG3 presentation irrespective of temperature. In contrast, TUM significantly decreased in the BM surrounding cardiomyocytes and capillaries after mild and deep hypothermic I/R, thus representing structural alterations of the BM in these groups.

CONCLUSION

The study demonstrates an early temperature-dependent processing of Col-IV as major component of the BM of cardiomyocytes and vascular endothelium. These observations support the protective effects of deep hypothermia during I/R. Furthermore, the results suggest an increased structural remodelling of the myocardial basement membrane with potential functional impairment during mild hypothermic I/R which may contribute to the progression to post-ischemic heart failure.

Cryptogenic left main thrombosis: successful mechanical clot retrieval with a self-expanding trapping device

We present the case of a 52-year-old male with ST-segment elevation myocardial infarction due to a spontaneous large left main thrombosis, without any angiographic evidence for coronary artery disease. After multiple unsuccessful attempts of thrombaspiration the large clot was mechanically retrieved by a flow restoration device that was primarily made for intracranial interventions. Intravascular ultrasound revealed marginal lumen narrowing after the intervention, but the final coronary angiogram showed a patent left main and there was no relevant stenosis remaining.

Transcatheter treatment of tricuspid regurgitation by caval valve implantation--experimental evaluation of decellularized tissue valves in central venous position

BACKGROUND

Caval valve implantation has been suggested for transcatheter treatment of severe tricuspid regurgitation (TR). Combining the interventional technique with the promising surgical experience with decellularized valves, we sought to evaluate the functional and structural outcome of decellularized pericardial tissue valves (dTVs) in the low-pressure venous circulation in a chronic model of TR.

METHODS AND RESULTS

Sixteen pericardial tissue valves were heterotopically implanted in the inferior and superior vena cava in a sheep model (54-98 kg; median 74.5 kg, n = 8) of severe TR. The devices were assembled using self-expanding nitinol stents and bovine pericardia decellularized by a detergent-based protocol (group dTV; n = 8). Glutaraldehyde-fixed pericardial tissue valves served as control (GaTV, n = 8). After 6 months, device function and structural maturation were analyzed using echocardiographic, histologic, immunohistologic, and electron microscopic approaches. After implantation, cardiac output increased significantly from 3.7 ± 1.1 l/min to 4.8 ± 1.1 l/min (P < 0.05) and competent valve function was verified by angiography. At 6 months, angiographic and echocardiographic evaluation revealed moderate to severe regurgitation in all GaTV. In contrast, five of the eight dTVs functioned well with only minor regurgitation. In these animals, autopsy revealed preserved valve structure with tender leaflets without signs of thrombosis or calcification. Conversely, GaTV showed severe degeneration with large calcification areas. Microscopic and histologic analysis confirmed endothelial repopulation in both valve types. However, additional interstitial reseeding was observed in decellularized valves.

CONCLUSIONS

In the venous circulation in severe TR, decellularized valves show superior functional performance compared to Ga-fixed tissue valves. Macroscopic and microscopic analyses suggest preserved structural integrity and advanced endothelial and interstitial repopulation with evidence of less degradation in dTV. © 2014 Wiley Periodicals, Inc.

Increased levels of circulating arginase I in overweight compared to normal weight adolescents

BACKGROUND AND AIMS

Overweight and the metabolic syndrome have become major problems, especially in children and adolescents. Obesity at a young age increases the risk for cardiovascular diseases and diabetes mellitus later in life. An early event in the development of cardiovascular disease is endothelial dysfunction which is found in obese young individuals. Increased activity of the enzyme arginase has been described as a central mechanism for endothelial dysfunction, especially in patients with diabetes mellitus. The aim of the study was to determine plasma levels of arginase in overweight adolescents.

METHODS

Sixty-six male German adolescents (age: 15.2 ± 1.1 years old) were included. Thirty-one of them were overweight (>90th age-specific weight percentile). Plasma arginase I and tumor necrosis factor alpha (TNFα) were determined. In addition, clinical data were recorded and anthropometrical measurements of obesity were performed.

RESULTS

Overweight adolescents had a higher systolic blood pressure, lower high-density lipoprotein and increased levels of high-sensitive C-reactive protein (CRP). Circulating arginase I was elevated in overweight adolescents (95.8 ± 68.2 ng/ml) compared to normal weight adolescents (39.3 ± 26.9 ng/ml, p < 0.001) and correlated with markers of obesity. There was no difference between the two groups regarding TNFα.

CONCLUSIONS

We demonstrate that arginase I levels are increased in obese adolescents. Knowing the important role for arginase in endothelial dysfunction, elevated levels of arginase I may represent a link between obesity, endothelial dysfunction and related comorbidities.

Altered red blood cell distribution width in overweight adolescents and its association with markers of inflammation

BACKGROUND

Obesity and the metabolic syndrome are dramatically increasing problems. Red blood cell distribution width (RDW), the variability in size of circulating red blood cells, has been demonstrated to be altered in different clinical settings. This analysis aimed to investigate the relationship between RDW and obesity in adolescents and in an animal model of diet-induced obesity (DIO).

METHODS

Seventy-nine male adolescents (aged 13-17 years) were studied. Thirty-seven of them were overweight (body mass index ≥ 90th percentile). RDW, markers of inflammation and stem cell factor (SCF) were determined. In an animal study, mice were fed with different diets for 15 weeks. RDW was determined using an animal blood count machine.

RESULTS

RDW differed significantly between normal-weight adolescents (13.07 ± 0.09) and overweight adolescents (13.39 ± 0.10, P = 0.015), whereas erythrocyte counts and haematocrit did not differ. RDW correlated to markers of inflammation and inversely to SCF. In the mice animal model, nutritional changes increased RDW, whereas overweight per se did not change RDW.

CONCLUSIONS

RDW is elevated in overweight and reflects the inflammatory state. RDW potentially represents an additional and cost-effective tool to indicate inflammation. Future studies are needed to understand the differential influences of nutrition and overweight on RDW.

Renal denervation in the treatment of drug-resistant hypertension: current knowledge and future perspectives

Resistant hypertension remains a challenging issue even for modern medicine. Therefore, research is focusing on the development of new technologies to optimize the treatment of this condition. It has been demonstrated that the dysfunction of the sympathetic nervous system is crucial in the development and maintenance of advanced stages of hypertension. Based on these findings, clinical trials have recently shown that catheter-based percutaneous renal denervation therapy is safe and effective in the treatment of resistant hypertension. This review discusses the current scientific knowledge of renal denervation therapy in resistant hypertension, including the different methods that have been described in the literature so far, as well as limitations of the available data. Furthermore, new potential targets for this fascinating therapy will be addressed.

Smelling heart failure from human skin odor with an electronic nose

The human body odor contains different volatile organic compounds which can be used as biomarkers for various diseases. The early detection of heart failure (HF) through periodical screening provides an early treatment application. Therefore we have developed a completely new non-invasive method to identify HF applying an "electronic nose" (e-nose) which provides a "smelling" of the disease based on the analysis of sweat volatile gases from the skin surface. For this e-nose a special applicator carrying the sensor chip was developed which can be applied directly on the skin surface. 27 patients with decompensated HF (DHF), 25 patients with compensated HF (CHF, mean age 70.72 ± 12.02) and 28 controls (CON) were enrolled in this first pilot study.

Unmasked superoparaseptal pathway conduction due to atrial fibrillation in a patient with left ventricular dysfunction. Rapid recovery after successful radiofrequency ablation

We report the case of a 56-year-old woman with newly diagnosed atrial fibrillation (AF) and severe left ventricular (LV) dysfunction caused by rapid conduction via an accessory pathway (AP), mimicking left bundle branch block, as the first clinical manifestation of Wolff-Parkinson-White (WPW) syndrome. Electrical cardioversion of the AF revealed a short PR interval and a delta wave, which was positive in leads I, II, aVL, and V2 and negative in lead V1 with a transition zone between V1 and V2. Radiofrequency catheter ablation of a superoparaseptal pathway was accompanied by rapid recovery from LV systolic dysfunction.