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Seventeen pharmaceutically active compounds and 22 other trace organic pollutants were analysed regularly in the influent and permeate from a semi-real plant treating municipal wastewater. The plant was operated during 29 months with different configurations which basically differed in the type of biomass present in the system. These processes were the integrated fixed-film activated sludge membrane bioreactor (IFAS-MBR), which combined suspended and attached biomass, the moving bed membrane bioreactor (MBMBR) (only attached biomass) and the MBR (only suspended biomass). Moreover, removal rates were compared to those of the wastewater treatment plant (WWTP) operating nearby with conventional activated sludge treatment. Reverse osmosis (RO) was used after the pilot plant to improve removal rates. The highest elimination was found for the IFAS-MBR, especially for hormones (100% removal); this was attributed to the presence of biofilm, which may lead to different conditions (aerobic-anoxic-anaerobic) along its profile, which increases the degradation possibilities, and also to a higher sludge age of the biofilm, which allows complete acclimation to the contaminants. Operating conditions played an important role, high mixed liquor suspended solids (MLSS) and sludge retention time (SRT) being necessary to achieve these high removal rates. Although pharmaceuticals and linear alkylbenzene sulfonates showed high removal rates (65-100%), nonylphenols and phthalate could only be removed to 10-30%. RO significantly increased removal rates to 88% mean removal rate.

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We compare measurements of the Brownian relaxation response of magnetic nanobeads in suspension using planar Hall effect sensors of cross geometry and a newly proposed bridge geometry. We find that the bridge sensor yields six times as large signals as the cross sensor, which results in a more accurate determination of the hydrodynamic size of the magnetic nanobeads. Finally, the bridge sensor has successfully been used to measure the change in dynamic magnetic response when rolling circle amplified DNA molecules are bound to the magnetic nanobeads. The change is validated by measurements performed in a commercial AC susceptometer. The presented bridge sensor is, thus, a promising component in future lab-on-a-chip biosensors for detection of clinically relevant analytes, including bacterial genomic DNA and proteins.

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In this work the effectiveness of membrane bioreactors as advanced treatment on the removal of emergent and priority organic compounds in wastewater treatment plants has been evaluated during a one-year monitoring study. The studied wastewater treatment plant operates with flat sheet and hollow fibre membranes in two parallel lines. Moreover, a reverse osmosis module connected in series after the hollow fibre membrane was evaluated for one month. Comparison of membrane bioreactor and conventional activated sludge treatment was also investigated, as well as the influence of the physicochemical properties of the compounds on the removal rates achieved. Sixteen pharmaceutical compounds belonging to seven therapeutic groups and eight priority organic pollutants, including linear alkylbenzene sulfonates, nonylphenol and its ethoxylates and phthalate, were monitored. The highest mean concentrations corresponded to priority organic pollutants (309 µg L(-1) of linear alkylbenzene sulfonate C(12)) followed by pharmaceutical compounds (24.5 µg L(-1) of ibuprofen). No significant difference of effectiveness was found among flat sheet and hollow fibre membranes. However, an improvement was obtained with the addition of a reverse osmosis module for most of the compounds. Biodegradation has been shown as the main route involved in the removal of organic compounds during both technologies.

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The occurrence of Transparent Exopolymer Particles (TEP), an acidic fraction of polysaccharides, was monitored for more than six months in the activated sludge of three MBR units, and the relationship between TEP and other fouling indicators was studied. These compounds consist mainly of exopolysaccharides of a sticky nature, a characteristic which makes them a group of interesting substances in processes like sedimentation, flocculation and membrane fouling. The relationship between capillary suction time (CST) and polysaccharides (PS) was linear for the three tested sludges, although the correlation with TEP concentrations was stronger. A slight linear correlation of both TEP and PS was found with the critical flux (CF) measured with a small filtration test cell, which was submerged in the membrane tank to assess the filterability performance of the sludge in situ. However, the correlation CF-PS was clearer. The relationship between TEP, polysaccharides and sludge filterability highlights the potential of this parameter for the monitoring of membrane systems.

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The volume amplified magnetic nanobead detection assay [Strömberg, M., Göransson, J., Gunnarsson, K., Nilsson, M., Svedlindh, P., Strømme, M., 2008. Nano Letters 8, 816-821] was investigated with respect to bead size, bead surface coverage of probe oligonucleotides, bead concentration and rolling circle amplification (RCA) time, with the objective to improve the understanding of the microscopic mechanisms influencing the assay. The most important findings for future biosensor development were the following: (i) small beads exhibit a much reduced tendency to cross-link several RCA products, thus enabling use of both complex magnetisation turn-on and turn-off detection strategies, whereas larger beads only allow for turn-off detection; (ii) small beads exhibit faster immobilisation kinetics, thus reducing the time for diagnostic test completion, and also immobilise in larger numbers than larger beads. Finally, (iii) by demonstrating qualitative dual-target detection of bacterial DNA sequences using 130 and 250nm beads, the bioassay was shown to allow for multiplexed detection.

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HIV infection is increasing in minority groups, particularly in African American and Hispanic women. Although the incidence of HIV dementia has decreased since the advent of highly active antiretroviral treatment, prevalence of neurocognitive complications has increased as patients are now living longer. This study's purpose was to determine the psychometric properties of the Spanish-language HIV Dementia Scale (HDS) in a group of HIV-infected women. We recruited 96 women: 60 HIV-seropositive and 36 HIV-seronegative. Modification of the HDS into a Spanish-language version consisted of translating the instructions, substituting four words in Spanish (gato, media, azul, piña), increasing 1 second in the psychomotor speed because the Spanish alphabet has more letters than the English alphabet, and not offering clues for memory recall. Cognitive impairment (CI) was defined according to the modified American Academy of Neurology HIV-dementia criteria including an asymptomatic CI group. Statistical analysis consisted of analysis of variance to determine group differences and receiver operator characteristics (ROC) to determine the optimal cutoff point for the screening of CI. HDS-Spanish total score and subscores for psychomotor speed and memory recall showed significant differences between HIV-seronegative and women with HIV-dementia (p < 0.001) and between HIV-seropositive women with normal cognition and those with HIV-dementia (p < 0.001). The optimal cutoff point of 13 or less had performance characteristics of 87% sensitivity and 46% specificity for HIV-associated CI (50.0% positive predictive value, 85.0% negative predictive value). The HDS-Spanish translation offers a useful screening tool with value for the identification of Hispanic women at risk of developing HIV-associated symptomatic neurocognitive disturbances.

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BACKGROUND: Many novel techniques have been described for "minimally invasive" congenital cardiac operations to achieve an improved cosmetic result. There is little information on incorporation of such techniques into fast-track congenital heart operations. METHODS: We have developed an approach to fast-track congenital heart operations, which includes a cosmetic approach for repair of congenital heart defects without sacrificing adequate exposure or requiring specialized equipment, along with a simple approach to intraoperative anesthetic management that allows extubation in the operating room. The heart is exposed through a short midline skin incision and a full median sternotomy. The conventional technique of cannulation is performed. Between October 1997 and January 1999, 88 patients were operated on with this method. Cardiac anomalies included simple and complex ostium secundum atrial septal defect, sinus venous atrial septal defect, partial atrioventricular septal defect, simple and complex ventricular septal defect, and bicuspid aortic valve stenosis. RESULTS: There were no operative or late deaths. The majority of patients were extubated in the operating room or within 2 hours of operation. No patient underwent reoperation and the mean length of hospital stay was 3.9 days. Sternal instability or wound infection were not observed. CONCLUSIONS: We believe that our approach to fast-track congenital heart operation is safe and effective. The surgical technique provides good exposure and has excellent cosmetic results. Moreover, it is easy to learn and, if necessary, the surgeon can quickly gain direct access to the heart. The anesthetic management facilitates early tracheal extubation and a shorter duration of postoperative stay.

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BACKGROUND: Conversion to total extracardiac cavopulmonary anastomosis is an option for managing patients with dysfunction of a prior Fontan connection. METHODS: Thirty-one patients (19.9 +/- 8.8 years) underwent revision of a previous Fontan connection to total extracardiac cavopulmonary anastomosis at four institutions. Complications of the previous Fontan connection included atrial tachyarrhythmias (n = 20), progressive heart failure (n = 17), Fontan pathway obstruction (n = 10), effusions (n = 10), pulmonary venous obstruction by an enlarged right atrium (n = 6), protein-losing enteropathy (n = 3), right atrial thrombus (n = 2), subaortic stenosis (n = 1), atrioventricular valve regurgitation (n = 3), and Fontan baffle leak (n = 5). Conversion to an extracardiac cavopulmonary connection was performed with a nonvalved conduit from the inferior vena cava to the right pulmonary artery, with additional procedures as necessary. RESULTS: There have been 3 deaths. Two patients died in the perioperative period of heart failure and massive effusions. The third patient died suddenly 8 months after the operation. All surviving patients were in New York Heart Association class I (n = 20) or II (n = 7), except for 1 patient who underwent heart transplantation. Early postoperative arrhythmias occurred in 10 patients: 4 required pacemakers, and medical therapy was sufficient in 6. In 15 patients, pre-revision arrhythmias were improved. Effusions resolved in all but 1 of the patients in whom they were present before revision. The condition of 2 patients with protein-losing enteropathy improved within 30 days. CONCLUSIONS: Conversion of a failing Fontan connection to extracardiac cavopulmonary connection can be achieved with low morbidity and mortality. Optimally, revision should be undertaken early in symptomatic patients before irreversible ventricular failure ensues.

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BACKGROUND: After a modified Fontan procedure with atriopulmonary or atrioventricular conduit, some patients present stress intolerance, supraventricular arrhythmia, recurrent pleuropericardial or ascitic effusions, and protein-losing enteropathy, all of which are signs that the previous procedure has failed. The aim of this study was to evaluate the midterm outcome after surgical therapy for this condition. MATERIAL AND METHODS: Between August 1994 and December 1997, nine patients (6 males and 3 females), age 10 to 39 (mean 21.5) years, underwent conversion of previous modified Fontan procedure to total extracardiac cavo-pulmonary connection. Time from the previous procedure was 6 to 18 years (mean 10). Diagnosis was tricuspid atresia with pulmonary stenosis (n = 2), double-inlet left ventricle and concordant ventriculoarterial connection (n = 3), double-inlet left ventricle and discordant ventriculoarterial connection (n = 3), Holmes heart (n = 1). Nine patients presented decreased stress tolerance, seven had arrhythmia, five had pleuropericardial effusions and two had protein-losing enteropathy. In all but one patient, right atrial pressure was higher than 15 mmHg, while in six patients the cardiac index was less than 2 l/min/m2. A polytetrafluoroethylene non-valved conduit was interposed between the inferior vena cava and the right pulmonary artery for conversion in all patients. A bidirectional cavo-pulmonary anastomosis (modified Glenn) was associated in all patients. Evaluation was done by NYHA Class and by an arbitrary score assigned to patients based on 7 parameters. RESULTS: There was no perioperative mortality. All patients were clinically improved at a mean follow-up of 24 months (range: 3 to 46). No patient had effusions, and the arrhythmias disappeared in 4 patients and were controlled by medical therapy in one. The two patients with protein-losing enteropathy improved markedly within 30 days and the score dropped below 10 points. CONCLUSIONS: The conversion of the modified Fontan procedure to total extracardiac cavo-pulmonary connection improves clinical condition by decreasing the right atrium-pulmonary gradient and right atrial preload, and by providing a laminar cavo-pulmonary flow without any need for intracardiac anastomoses. This procedure should be undertaken early in this subset of patients, before ventricular failure ensues.

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