Hypertension,hyperreninemia and a solitary renal cyst in an adolescent

Solitary renal cysts associated with hypertension and documented hyperreninemia are relatively uncommon. A 13 year old boy with these findings is described (pressure 160/120 mm Hg). Contrast studies of the urinary tract and arteriography with selective renal vein sampling demonstrated a solitary cyst in the right kidney. The ratio of plasma renin activity in the right renal vein to left renal vein (RRV:LRV) was 2.35:1. After drainage of the cyst, there was a marked reduction in both systolic and diastolic pressures (126/84 mm Hg). Hypertension has not recurred during 14 months' follow up.     

Hemodynamic observations during and after pulmonary artery banding

Analysis of cardiac catheterization in 25 patients with nonrestrictive ventricular septal defect (Prv/Plv > 0.6) shows that the pulmonary vascular resistance and systemic vascular resistance function as resistances in parallel. Furthermore, studies in the presence of right ventricular outflow obstruction, by either pulmonary artery band (9 patients) or pulmonary stenosis and ventricular septal defect with left-to-right shunting (12 patients), show that the right ventricular outflow obstruction (band) functions as a resistance in series with the pulmonary vascular resistance. The sum of pulmonary vascular resistance plus band resistance is in parallel with systemic resistance. This concept allows better explanation of the great pressure variability across bands observed at operation. It is impossible to completely evaluate a pulmonary artery band with pressures alone. Flow measurements are necessary for better understanding of pulmonary artery bands. The variability of clinical response after banding may be explained by the variations in pulmonary vascular resistance and systemic vascular resistance during and after pulmonary artery banding.     

Effect of oral contraceptives on urinary metabolite excretions after administration of L-tryptophan or L-kynurenine sulfate

The metabolism of orally administered doses of L-tryptophan and L-kynurenine sulfate has been compared in 18 women using an estrogen-containing oral contraceptive, and 12 controls who were not taking any steroid preparations. Both compounds produced higher urinary excretions of several intermediates of the tryptophan-nicotinic acid ribonucleotide pathway in the oral contraceptive users than in the controls, indicating that these steroids have an effect beyond the tryptophan oxygenase-mediated step. Increases in the ratio of 3-hydroxykynurenine to 3-hydroxyanthranilic acid excreted were consistent with an inhibition of kynureninase, due to impaired pyridoxal phosphate function, but only tryptophan loading caused an elevated xanthurenic acid excretion. This difference may have been due to an influence of the kidney on kynurenine metabolism.     

Comparative effect of photodynamic therapy on separated or mixed cultures of Streptococcus mutans and Streptococcus sanguinis

Antimicrobial photodynamic therapy (aPDT) has shown to exert a bactericidal effect against Streptococcus sanguinis and Streptococcus mutans. However, this efficacy has been reported for either type of bacteria separately. Bacterial suspensions of both strains, separately or together, were treated with concentrations of methylene blue (MB) and rose bengal (RB). Suspensions were irradiated with a light–emitting diode lamp (λ center at 625 nm for MB and λ center at 515 nm for RB) using a fluence of 18 J/cm². RB-aPDT at concentrations of 0.16–0.62 and 0.16–0.31 μg/mL, and MB-aPDT at concentrations of 0.62–1.25 and 0.31–1.25 μg/mL inhibited the growth of S. mutans and S. sanguinis respectively by 6 log₁₀. In suspensions of both strains together, the same 6 log₁₀ reduction in bacterial growth was achieved using the same concentrations of each photosensiziser.In conclusion, RB-aPDT and MB-aPDT appear to exert the same bactericidal effect against suspensions of S. sanguinis and S. mutans either for single strain treatment or for samples constituted by both bacteria mixed together. RB shows to be slightly more efficient than MB.     

Streptococcus mutans photoinactivation using a combination of a high potency photopolymerizer and rose bengal

BackgroundLong treatment periods to reach a substantial inactivation of microorganisms are one of the critical challenges in the photodynamic therapy field.MethodsPlanktonic suspensions of Streptococcus mutans were treated in different groups: presence of rose bengal (RB at 2 μM) and light exposure by a new high potency photopolymerizer (L at wavelength = 440–480 nm; dosimetry = 96 J/cm² – 40 s of irradiation; potency density = 1200 mW/cm²; dosage = 48 J) – RB+L+ (PDT), just with dye – RB+L−, just with light – RB−L+ and absence of light and dye RB−L− (control group). Aliquots of each group were transferred to Petri dishes to colony counting (CFU/mL) with the data transformed in log₁₀. The results were submitted to ANOVA and Tukey test at 5%.ResultsPDT group presented total eradication of microorganisms showing statistical difference with all the other groups (5.82 log reduction ≅ 99%).ConclusionThe high potency photopolymerizer in pulsed emission at an extra short irradiation and low concentration of rose bengal could be considered as a progressive alternative to the control of S. mutans suspensions.