The Influence of Modified Experimental Dental Resin Composites on the Initial In Situ Biofilm-A Triple-Blinded, Randomized, Controlled Split-Mouth Trial.

The purpose of the study was to investigate the bacterial viability of the initial biofilm on the surface of experimental modified dental resin composites. Twenty-five healthy individuals with good oral hygiene were included in this study. In a split-mouth design, they received acrylic splints with five experimental composite resin specimens. Four of them were modified with either a novel polymeric hollow-bead delivery system or methacrylated polymerizable Irgasan (Antibacterial B), while one specimen served as an unmodified control (ST). A delivery system based on Poly-Pore® was loaded with one of the active agents: Tego® Protect 5000 (Antiadhesive A), Dimethicone (Antiadhesive B), or Irgasan (Antibacterial A). All study subjects refrained from toothbrushing during the study period. Specimens were detached from the splints after 8 h and given a live/dead staining before fluorescence microscopy. A Friedman test and a post hoc Nemenyi test were applied with a significance level at p < 0.05. In summary, all materials but Antibacterial B showed a significant antibacterial effect compared to ST. The results suggested the role of the materials' chemistry in the dominance of cell adhesion. In conclusion, dental resin composites with Poly-Pore-loaded active agents showed antibacterial effectiveness in situ.

Usefulness of multidetector CT imaging to assess vascular stents in children with congenital heart disease: an in vivo and in vitro study.

OBJECTIVE: To evaluate varying CT settings to visualize pediatric vascular stents in comparison to digital angiography (DA). BACKGROUND: There is a great clinical interest in substituting noninvasive methods to follow up children with congenital heart disease after interventional treatment. MATERIALS AND METHODS: CT studies in small children with transcatheter placed stents were reviewed, retrospectively. Furthermore, eight stents were implanted in tubes and partially obstructed. CT exams were performed on varying scanners (4 up to 64 slices) with corresponding tube settings. The effects of dose on image quality were evaluated regarding stent size, strut thickness, and in-stent stenoses in comparison to DA. RESULTS: Fourteen children with 28 implanted stents were identified. Significant differences between higher and lower radiation settings were not found, corresponding with the phantom, where moderate tube setting showed the best results. In vitro, there was an improvement with increasing number of detector rows, which resulted in a decrease of stent strut overestimation (295% down to 201%; P < 0.0001) and a better agreement with DA measurements for mild (78% up to 91%; P = 0.003) and moderate in-stent stenoses (80% up to 99%; P = 0.0001). CONCLUSION: Higher radiation exposure settings did not improve image quality, suggesting that the exams could be performed at a lower radiation dose.

CT of pediatric vascular stents used to treat congenital heart disease.

OBJECTIVE: The purpose of our study was to assess the visibility of lumen narrowing of pediatric vascular stents using various CT dose parameters in an in vitro model. MATERIALS AND METHODS: Ten steel stents of varying designs and sizes commonly used in the treatment of congenital heart disease were implanted in polyvinyl chloride (PVC) tubes and three of the 10 stents were partially obstructed with wax by filling 25% (mild) to 60% (moderate) of the lumen with contrast material. On a 64-MDCT scanner, the stents were scanned at tube voltages (kVp) of 80, 100, and 120 and at tube currents (mA) of 40, 80, 120, and 160. CT measurements of inner-stent diameter, strut thickness, and percent lumen (in-stent) stenoses were compared with biplane fluoroscopy of digital angiography. RESULTS: The stent diameter and percent stenosis on all CT images were consistently smaller than measured on digital angiography but were highly correlated (r = 0.97; p < 0.0001) with improvement as stent diameter increased (93% agreement with digital angiography for 4-mm stent, up to 99% for 25-mm stent; p = 0.001). Moderate stenosis could be assessed better than mild stenosis (99% vs 91% agreement with digital angiography; p = 0.003). Increasing exposure settings improved CT correlation of all measurements for mA up to 120 and kVp up to 100 (98.1% agreement). Higher settings did not improve accuracy (93.9% for 160 mA at 120 kVp; p = 0.03). CONCLUSION: CT is feasible to assess lumen narrowing of pediatric vascular stents at a wide range of tube settings. The study suggests that it is possible to lower the radiation exposure settings without loss in image quality or accuracy in detecting in-stent stenoses.

Evolution of large-vessel arteriopathy in paediatric patients with chronic kidney disease.

UNLABELLED: This observational study was designed to verify the hypothesis that the treatment modality significantly affects the evolution of CKD-associated arteriopathy. PATIENTS: Paediatric patients (mean age 13.8 +/- 4.2 years) with chronic kidney disease (CKD) stages 3-5, including 24 patients with mean GFR 54 +/- 21 ml/min/1.73 m(2) (CKD group) and 32 patients in end-stage renal disease, of whom 19 received a renal allograft (D-Rtx) and 13 remained on dialysis (D-D). METHODS: Sonography of the common carotid artery was performed at baseline and after 12 months. Intima-media thickness (IMT) and the cross-sectional areas of the vessel wall (WCSA) and lumen (LCSA) were measured and normalized to age (SDS). RESULTS: At baseline IMT-SDS and WCSA-SDS were increased above normal, and were significantly higher in D than in CKD patients (P < 0.001). IMT-SDS increased over time in CKD and D-D patients (1.4 +/- 1.7 to 2.1 +/- 1.2, P = 0.05). In contrast, IMT-SDS (2.8 +/- 0.6 to 2.0 +/- 0.6, P < 0.005) decreased in those D-Rtx patients who had elevated values prior to transplantation. The total number of patients with elevated cIMT-SDS changed from 7 to 13 in the 24 CKD, from 8 to 11 in the 13 D-D and from 11 to 12 in the 19 D-Rtx patients. While IMT-SDS was independently correlated with blood pressure and serum phosphate in the CKD and D patients, only total dialysis vintage (r = 0.50; P < 0.05) and the IMT-SDS attained at the time of grafting (r = 0.46, P < 0.05) correlated with IMT-SDS 1 year post-Rtx. CONCLUSION: While vascular lesions rapidly progress in CKD and D patients, abolition of the uraemic state by Rtx leads to stabilization or partial regression of CKD-associated arteriopathy. Cumulative dialysis duration and the degree of arterial damage prevalent at the time of grafting are the main determinants of persistent arteriopathy 1 year after Rtx.

Aging sensitizes toward ROS formation and lipid peroxidation in PS1M146L transgenic mice.

Mutations in the presenilins (PS) account for the majority of familial Alzheimer disease (FAD) cases. To test the hypothesis that oxidative stress can underlie the deleterious effects of presenilin mutations, we analyzed lipid peroxidation products (4-hydroxynonenal (HNE) and malondialdehyde) and antioxidant defenses in brain tissue and levels of reactive oxygen species (ROS) in splenic lymphocytes from transgenic mice bearing human PS1 with the M146L mutation (PS1M146L) compared to those from mice transgenic for wild-type human PS1 (PS1wt) and nontransgenic littermate control mice. In brain tissue, HNE levels were increased only in aged (19-22 months) PS1M146L transgenic animals compared to PS1wt mice and not in young (3-4 months) or middle-aged mice (13-15 months). Similarly, in splenic lymphocytes expressing the transgenic PS1 proteins, mitochondrial and cytosolic ROS levels were elevated to 142.1 and 120.5% relative to controls only in cells from aged PS1M146L animals. Additionally, brain tissue HNE levels were positively correlated with mitochondrial ROS levels in splenic lymphocytes, indicating that oxidative stress can be detected in different tissues of PS1 transgenic mice. Antioxidant defenses (activities of antioxidant enzymes Cu/Zn-SOD, GPx, or GR) or susceptibility to in vitro oxidative stimulation was unaltered. In summary, these results demonstrate that the PS1M146L mutation increases mitochondrial ROS formation and oxidative damage in aged mice. Hence, oxidative stress caused by the combined effects of aging and PS1 mutations may be causative for triggering neurodegenerative events in FAD patients.

Normative values for intima-media thickness and distensibility of large arteries in healthy adolescents.

OBJECTIVE: Sonographic evaluation of arterial wall morphology and elasticity is increasingly accepted as a non-invasive tool in cardiovascular assessment. Several studies suggest that intima-media thickness (IMT) and arterial elasticity indices may sensitively reflect different vasculopathic processes in children. However, normative values and the impact of adolescent growth are largely unknown. METHODS: We assessed the IMT of the common carotid (cIMT) and femoral arteries (fIMT), carotid elasticity indices and interacting anthropometric factors in 247 healthy subjects aged 10-20 years. RESULTS: cIMT, fIMT, incremental elastic modulus (Einc) and circumferential wall stress (CWS) were positively, and distensibility coefficient (DC) inversely, correlated with age, height, body mass index (BMI), systolic blood pressure (BP) and brachial pulse pressure (r = 0.56 to -0.45, P < 0.05 to 0.0001). DC (r = -0.29, P < 0.0001) and stiffness index beta (r = 0.25, P < 0.0001), but not Einc, were significantly associated with cIMT independently of age. All vascular parameters showed non-Gaussian distributions. Excessively high IMT was associated with BMI and pulse pressure above the 90th percentile, and elevated Einc with high-normal BMI. Multivariate analysis identified independent positive effects of standardized BMI and brachial pulse pressure on normalized cIMT, negative effects of systolic BP and cIMT on DC, a positive effect of cIMT on stiffness, and positive effects of systolic BP and BMI on Einc and CWS. CONCLUSIONS: Morphological and functional measures of large arteries should be normalized to take account of changes during adolescence and skewed distributions. Relative body mass, systolic blood pressure and/or pulse pressure are determinants of IMT and elasticity.

Altered morphologic properties of large arteries in children with chronic renal failure and after renal transplantation.

Increased intima-media thickness of the carotid arteries (cIMT) has been found in young adults with childhood-onset chronic kidney disease (CKD). The disease stage at which these patients first develop abnormalities of arterial texture is unknown. The objective of this study was to determine the onset and character of arterial changes in children aged 10 to 20 yr with different stages of CKD and to identify risk factors for early arteriopathy. High-resolution ultrasonography was conducted of common cIMT and femoral superficial artery IMT. Fifty-five children with stages 2 to 4 CKD (GFR 51 +/- 31 ml/min per 1.73 m2), 37 on dialysis, and 34 after renal transplantation (Rtx; GFR 73 +/- 31 ml/min per 1.73 m2) were studied. Control subjects were 270 healthy children, matched for age and gender. Compared with control subjects, cIMT, femoral superficial artery IMT (both as absolute values and as SD score of median of normal value), wall cross-sectional area, and lumen cross-sectional area of carotid artery were significantly increased in all patient groups and most markedly abnormal in dialysis patients. cIMT in CKD and Rtx patients was significantly lower in comparison with dialysis patients. cIMT correlated with mean past serum Ca x P product, the cumulative dose of calcium-based phosphate binders, and the time-averaged mean calcitriol dose. The cumulative phosphate binder intake, time-averaged Ca x P product, and young age were independent predictors of an increased cIMT. In children with CKD, thickening of IMT occurs early in the course of disease and is most marked in dialyzed patients. The changes may be partly reversible after Rtx.

Hyperforin modifies neuronal membrane properties in vivo.

Hyperforin, the major active constituent of St. John Wort (SJW) extract, affects several neurotransmitter systems in the brain putatively by modulation of the physical state of neuronal membranes. Accordingly, we tested the effects of SJW extract and of hyperforin on the properties of murine brain membrane fluidity. Oral administration of SJW extract and of hyperforin sodium salt results in significant hyperforin brain levels. Treatment of mice with hyperforin leads to decreased annular- and bulk fluidity and increased acyl-chain flexibility of brain membranes. All hyperforin related changes of membrane properties were significantly correlated with the corresponding hyperforin brain levels. Our data emphasises a membrane interaction of hyperforin that possibly contributes to its pharmacological effects.