Vesicoureteral reflux in patients diagnosed with pyeloureteral junction obstruction. Is screening justified? / Reflujo vesicoureteral en pacientes diagnosticados de estenosis de la unión pieloureteral. ¿Está justificado el screening?

INTRODUCTION: The prevalence of vesicoureteral reflux (VUR) concomitant with pyeloureteral junction obstruction (PUJO) ranges from 5.2% to 18%. Today, there is no consensus on whether routine screening should be performed or not to rule out reflux, and it can be limited to selected patients. OBJECTIVES: To study VUR prevalence in patients diagnosed with PUJO, estimate reflux levels in patients with positive study, and limit serial voiding cystourethrogram (SVCU) or ultrasound cystography to selected patients (dilated ureter at ultrasound imaging and previous UTI). MATERIALS AND METHODS: Observational, retrospective study carried out in 74 patients undergoing surgery for PUJO. Information on sex, preoperative VUR screening, results (positive or negative for VUR), and reflux levels was collected. RESULTS: 53 cases (71.6%) were male and 21 (28.4%) were female. Reflux screening was performed in 55 patients (74.3%), vs. 18 (24.3%) where no study was carried out. 16.2% of cases with VUR preoperative study were managed using ultrasound cystography. The preoperative study was positive in 6 out of the 73 patients (1 patient was excluded after being diagnosed with posterior urethral valves), which means VUR prevalence in patients already diagnosed with PUJO was 10.7%. Of the six cases, one case was grade I, two cases were grade II, one case was grade III, one case was grade IV, and one case was grade V. CONCLUSIONS: VUR has a slightly higher incidence in patients diagnosed with pyeloureteral junction obstruction than in the general population. Routine screening of vesicoureteral reflux is unnecessary, unless in case of previous urinary infection, dilated ureter at ultrasound imaging, or suspected secondary cause.

INTROUCCION: La concomitancia entre la estenosis de la unión pieloureteral (EPU) y el reflujo vesicoureteral (RVU) se sitúa entre el 5,2 y el 18%. Actualmente, no existe consenso sobre la realización de screening rutinario para descartar dicho reflujo, pudiendo limitarlo a pacientes seleccionados. OBJETIVOS: Estudiar la prevalencia del RVU en los pacientes diagnosticados de EPU. Estimar el grado de reflujo en aquellos pacientes con estudio positivo. Limitar la realización de cistouretrografía miccional seriada CUMS o de ecocistografía a pacientes seleccionados (uréter dilatado visible en ecografía, ITU previa). MATERIAL Y METODOS: Estudio observacional y retrospectivo sobre 74 pacientes intervenidos de EPU. Se ha recogido información acerca del sexo, realización de despistaje preoperatorio de RVU, los resultados (positivo o negativo para RVU) y grado de reflujo. RESULTADOS: 53 casos fueron masculinos (71,6%) y 21 (28,4%) femeninos. El despistaje de reflujo fue realizado en 55 pacientes (74,3%) frente a 18 (24,3%) en los que no se realizó ningún estudio. El 16,2% de los casos en los que se realizó el estudio preoperatorio de RVU fueron abordados mediante ecocistografía, siendo el estudio preoperatorio positivo en 6 pacientes del total de 73 estudiados (un paciente fue excluido por ser diagnosticado de válvulas de uretra posterior), lo que sitúa la prevalencia de RVU en pacientes ya diagnosticados de EPU en un 10,7%. De estos, un caso fue de grado I, dos grado II y un caso grado III, IV y V, respectivamente. CONCLUSIONES: El RVU en pacientes diagnosticados de estenosis de la unión pieloureteral presenta una incidencia ligeramente mayor que en la población general. El screening rutinario del reflujo vesicoureteral es innecesario, debiendo realizarse en casos que presenten infecciones urinarias previas, visualización del uréter dilatado en la ecografía o sospecha de causa secundaria.

First case of Streptococcus lutetiensis bacteremia involving a clindamycin-resistant isolate carrying the lnuB gene.

Here, we describe the first case of a Streptococcus lutetiensis isolate harboring the lnuB gene.

Bacteriological, biochemical, and immunological modifications in human colostrum after Holder pasteurisation.

OBJECTIVE: The objective of this work was to evaluate the effect of Holder pasteurisation of human colostrum on a variety of microbiological, biochemical, and immunological parameters. METHODS: Colostrum samples from 10 donors, and 8 samples of mature milk used as controls, were heated at 62.5°C for 30 minutes. Bacterial counts and the concentration of furosine, lactose, myoinositol, glucose, lactulose, cytokines, and immunoglobulins were determined before and after the heat treatment. RESULTS: Mean bacterial counts in nonpasteurised colostrum samples oscillated between 2.72 and 4.13 log10 colony-forming units per millilitre in the agar media tested. Holder pasteurisation led to the destruction of the bacteria originally present in the samples. Furosine was detected in all samples before pasteurisation and increased significantly after the heat treatment (from 6.60 to 20.59 mg/100 g protein). Lactulose content was below the detection limit in nonpasteurised colostrum, but it was detected in all samples and quantified in 7 of them (from 10.68 to 38.02 mg/L) after Holder pasteurisation. Lactose, glucose, and myoinositol concentrations did not change after Holder pasteurisation. The concentrations of most cytokines and immunoglobulins were significantly higher in colostrum than in mature milk samples. Immunoglobulin content, both in colostrum and in milk samples, was reduced during pasteurisation, whereas, among cytokines, only macrophage inflammatory protein-1ß, interleukin-7, and granulocyte-macrophage-colony-stimulating factor concentrations were affected by this heat treatment. CONCLUSIONS: Lactulose and furosine content could be used as heat treatment indicators in colostrum samples. Holder pasteurisation modified the immunological profile of both colostrum and mature milk.

Effect of prebiotic carbohydrates on the growth and tolerance of Lactobacillus.

Resistance to gastrointestinal conditions is a requirement for bacteria to be considered probiotics. In this work, we tested the resistance of six different Lactobacillus strains and the effect of carbon source to four different gastrointestinal conditions: presence of α-amylase, pancreatin, bile extract and low pH. Novel galactooligosaccharides synthesized from lactulose (GOS-Lu) as well as commercial galactooligosaccharides synthesized from lactose (GOS-La) and lactulose were used as carbon sources and compared with glucose. In general, all strains grew in all carbon sources, although after 24 h of fermentation the population of all Lactobacillus strains was higher for both types of GOS than for glucose and lactulose. No differences were found among GOS-Lu and GOS-La. α-amylase and pancreatin resistance was retained at all times for all strains. However, a dependence on carbon source and Lactobacillus strain was observed for bile extract and low pH resistance. High hydrophobicity was found for all strains with GOS-Lu when compared with other carbon sources. However, concentrations of lactic and acetic acids were higher in glucose and lactulose than GOS-Lu and GOS-La. These results show that the resistance to gastrointestinal conditions and hydrophobicity is directly related with the carbon source and Lactobacillus strains. In this sense, the use of prebiotics as GOS and lactulose could be an excellent alternative to monosaccharides to support growth of probiotic Lactobacillus strains and improve their survival through the gastrointestinal tract.

DNA delivery to 'ex vivo' human liver segments.

Hydrodynamic injection is an efficient procedure for liver gene therapy in rodents but with limited efficacy in large animals, using an 'in vivo' adapted regional hydrodynamic gene delivery system. We study the ability of this procedure to mediate gene delivery in human liver segments obtained by surgical resection. Watertight liver segments were retrogradely injected from hepatic vein with a saline solution containing a plasmid bearing the enhanced green fluorescent protein (eGFP) gene, under different conditions of flow rate (1, 10 and 20 ml s(-1)) and final perfused volume. Samples were cultured for 1 to 2 days and used for microscopy and molecular analysis of gene expression. The fluorescent and immunohistochemistry studies indicated that in segments injected at ≥10 ml s(-1), good and wide gene expression was present in the liver sections and the molecular analysis reinforced the histological observation in a quantitative manner (index of apparent gene delivery: 10(2)-10(4) eGFP DNA copy per 100 pg of total DNA; transcription index: 10(5)-2 × 10(6) eGFP RNA copy per 100 ng of total RNA). In addition, injected gold nanoparticles (15 nm diameter) suggested that DNA delivery to hepatocytes must involve a facilitated permeation process without membrane disruption. In summary, we show that retrograde venous injection of watertight human liver segment is an anadromous procedure that results in wide liver gene delivery and good gene expression. However, additional studies will be necessary to clarify the influence of the prolonged ischemia injury to hepatocytes in our model.

Use of chitosan for selective removal of beta-lactoglobulin from whey.

A method is described for selective removal of undenatured beta-lactoglobulin from cheese whey based on interactions between whey proteins and chitosan. Whey was previously clarified at pH 4.5 with addition of chitosan (25 mg/100 mL), and selective removal of beta-lactoglobulin was studied in the pH interval 4.6 to 6.5. Addition of chitosan caused selective precipitation of beta-lactoglobulin that increased with pH. The content of beta-lactoglobulin in whey decreased as the amount of chitosan added was increased. At pH 6.2, addition of 1.9 to 3.0 mg/mL of chitosan led to complete removal of beta-lactoglobulin, whereas at least 80% of the rest of whey proteins remained in solution. The production of cheese whey without beta-lactoglobulin could help to expand the applications of dairy by-products in food processing, and to isolate hypoallergenic whey protein concentrates.