Tunable fragmentation of organic molecules in laser ablation glow discharge time-of-flight mass spectrometry

A DC-pulsed glow discharge (GD) has distinct temporal regimes which are characterized by "softer” or "harder” ionization of analytes introduced into the discharge. It is thus possible to obtain both molecular weight and structural fragment information from the same spectra. In order to extend the capabilities of this technique a laser ablation (LA) sampling system was coupled to a DC-pulsed GD and to a time-of-flight (TOF) mass spectrometer (MS) for characterizing organic samples such as oleic acid, reserpine, two different peptides, and a polymer. Both hard and soft ionization regimes were studied. These LAGD-TOFMS results were compared to matrix-assisted laser desorption ionization (MALDI) spectra using the same compounds (i.e., analytes, concentration, and matrix). It was found that LAGD offers tunable ionization and provides a reduced matrix dependence. However, the sensitivity achieved by the prototype LAGD-TOFMS was significantly lower when compared with commercially available MALDI-TOFMS instrumentation. Since LAGD-TOFMS is rather new, some technical details to increase its sensitivity are discussed. Figure Schematics of molecular and structural information of oleic acid molecule during the different temporal regimes of a pulsed G

Clinical Characteristics and Management of Children with Ureteropelvic Junction Obstruction and Severe Vesicoureteral Reflux: Preliminary Results

Objective: The aim of this study was to investigate the physiopathology of isolated or coexisting ureteropelvic junction obstruction (UPJ-O) and high-grade vesicoureteral reflux (VUR), including the clinical characteristics and management.Summary background data: The association between UPJ-O and VUR was reported more frequently in boys with high-grade VUR; however, the physiopathology of concomitant UPJ-O and VUR is still unknown. Primary pyeloplasty, followed by ureteral reimplantation, if needed, has been widely accepted, although VUR should be treated first (most often by endoscopic treatment) in the presence of a functional obstruction.Methods: We reviewed the charts of 78 children with isolated or coexisting high-grade VUR/UPJ-O. Among the children, 14 had isolated UPJ-O, 16 had high-grade VUR/ UPJ-O, and 48 had high-grade VUR. Children with other urological or extrarenal conditions were excluded.Results: Patients with isolated UPJ-O showed significantly different clinical characteristics compared with the other two groups of patients with high-grade VUR. Among the patients of group 2, 3/13 (23%) showed progression from functional to obstructive UPJ-O after endoscopic treatment. All of them underwent secondary pyeloplasty, which was complicated at follow-up by VUR recurrence needing further endoscopic injection.Conclusion: We suggest that UPJ-O in high-grade VUR patients is just a complication of severe VUR that produces structural changes in predisposed children. The treatment of children with associated high-grade VUR/UPJ-O may be complicated by the progression of urinary flow obstruction or VUR recurrence after pyeloplasty. Endoscopic treatment of high-grade VUR is associated with a high rate of VUR recurrence in children requiring subsequent pyeloplasty.Keywords: Children, Endoscopic Treatment, Ureteropelvic Junction Obstruction, Vesicoureteral Reflu

Regular Consumption of a Flavanol-rich Chocolate can Improve Oxidant Stress in Young Soccer Players

The consumption of a diet rich in certain flavonoids, including the flavanol sub-class, has been associated with a reduced risk for vascular disease. We evaluated the effects of the regular consumption (14 d) of a flavanol-containing milk chocolate (FCMC) or cocoa butter chocolate (CBC) on variables related to vascular disease risk, oxidative stress and physical activity. Twenty-eight free-living, young (18–20 years old) male soccer players consumed daily 105 g of FCMC (168 mg of flavanols) or CBC (<5 mg of flavanols), as part of their normal diet. The consumption of FCMC was significantly associated with a decrease in diastolic blood pressure (-5 mm Hg), mean blood pressure (-5 mm Hg), plasma cholesterol (-11%), LDL-cholesterol (-15%), malondialdehyde (-12%), urate (-11%) and lactate dehydrogenase (LDH) activity (-11%), and an increase in vitamin E/cholesterol (+12%). No relevant changes in these variables were associated with CBC consumption. No changes in the plasma levels of (-)-epicatechin were observed following analysis of fasting blood samples. In conclusion, FCMC consumption was associated with changes in several variables often associated with cardiovascular health and oxidant stress. The presence of significant quantities of flavanols in FCMC is likely to have been one of the contributing factors to these results

Correlação entre as alterações osteocondrais evidenciadas à ressonância magnética e a progressão da doença

PURPOSE: To determine the consequences of the chronic use of systemic corticosteroids in children with juvenile rheumatoid arthritis by means of evaluating osteochondral effects depicted by magnetic resonance imaging. PATIENTS AND METHODS: We reviewed clinical and magnetic resonance imaging findings in 69 children (72 knees) with juvenile rheumatoid arthritis. Two groups were studied. Group I: 34 (49.3%) children had previous or current use of systemic corticotherapy (22 girls; 12 boys; mean age: 11.3 years; mean disease duration: 5.9 years; mean corticotherapy duration: 2.9 years; mean cumulative dose of previous corticosteroids: 5000 mg); Group II: 35 (50.7%) children had no previous use of corticosteroids (27 girls; 8 boys; mean age: 11.7 years; mean disease duration: 5.3 years). The groups were compared statistically. RESULTS: In the group that had received corticotherapy (Group I), osteochondral abnormalities were significantly correlated to long-standing disease (>;3.5 years; pOBJETIVO: Determinar as conseqüências do uso crônico de corticosteróides sistêmicos em crianças com artrite reumatóide juvenil através da avaliação dos efeitos osteocondrais à ressonância magnética. PACIENTES E MÉTODOS: Achados clínicos e imaginológicos (ressonância magnética) de 72 joelhos em 69 crianças com artrite reumatóide juvenil foram revisados. Trinta e quatro (49.3%) pacientes fizeram uso prévio de corticoterapia sistêmica (22 pacientes do sexo feminino; 12 pacientes do sexo masculino; idade média: 11.3 anos; duração média da doença: 5.9 anos; duração média da corticoterapia: 2.9 anos; dose média cumulativa de corticosteróides: 5000 mg); 35 (50.7%) pacientes não haviam feito uso prévio de corticoterapia sistêmica (27 pacientes do sexo feminino; 8 pacientes do sexo masculino; idade média: 11.7 anos; duração média da doença: 5.3 anos). RESULTADOS: No grupo que recebeu corticoterapia sistêmica prévia (Grupo I) a presença de alterações osteocondrais à ressonância magnética relacionou-se de uma forma estatisticamente significativa com longo tempo de duração da doença (>;3.5 years;

Modelo predictivo de comportamiento de barcos

El problema de simular los movimientos y la dinámica de un barco es estudiado principalmente para el desarrollo de simuladores de maniobra y entrenamiento. En general existen varios niveles posibles de solución, con diversos grados de complejidad y de exactitud. No obstante, todas las soluciones basadas en modelos matemáticos conducen naturalmente a dos acercamientos básicos: modelos dinámicos de desplazamiento, y modelos cinemáticos de predicción. En este trabajo se presenta el desarrolló de un nuevo modelo matemático simplificado, que permite predecir la dinámica de maniobra y la cinemática de movimiento, en base a las características del barco, y a los valores de velocidades y aceleraciones instantáneas.Eje: Arquitectura, Redes y Sistemas OperativosRed de Universidades con Carreras en Informática (RedUNCI

Modelo predictivo de comportamiento de barcos

El problema de simular los movimientos y la dinámica de un barco es estudiado principalmente para el desarrollo de simuladores de maniobra y entrenamiento. En general existen varios niveles posibles de solución, con diversos grados de complejidad y de exactitud. No obstante, todas las soluciones basadas en modelos matemáticos conducen naturalmente a dos acercamientos básicos: modelos dinámicos de desplazamiento, y modelos cinemáticos de predicción. En este trabajo se presenta el desarrolló de un nuevo modelo matemático simplificado, que permite predecir la dinámica de maniobra y la cinemática de movimiento, en base a las características del barco, y a los valores de velocidades y aceleraciones instantáneas.Eje: Arquitectura, Redes y Sistemas OperativosRed de Universidades con Carreras en Informática (RedUNCI