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Background: Legionella testing conducted at environmental laboratories plays an essential role in assessing the risk of disease transmission associated with water systems. However, drawbacks of culture-based methodology used for Legionella enumeration can have great impact on the results and interpretation which together can lead to underestimation of the actual risk. Up to 20% of the samples analysed by these laboratories produced inconclusive results, making effective risk management impossible. Overgrowth of competing microbiota was reported as an important factor for culture failure. For quantitative polymerase chain reaction (qPCR), the interpretation of the results from the environmental samples still remains a challenge. Inhibitors may cause up to 10% of inconclusive results. This study compared a quantitative method based on immunomagnetic separation (IMS method) with culture and qPCR, as a new approach to routine monitoring of Legionella. Results: First, pilot studies evaluated the recovery and detectability of Legionella spp using an IMS method, in the presence of microbiota and biocides. The IMS method results were not affected by microbiota while culture counts were significantly reduced (1.4 log) or negative in the same samples. Damage by biocides of viable Legionella was detected by the IMS method. Secondly, a total of 65 water samples were assayed by all three techniques (culture, qPCR and the IMS method). Of these, 27 (41.5%) were recorded as positive by at least one test. Legionella spp was detected by culture in 7 (25.9%) of the 27 samples. Eighteen (66.7%) of the 27 samples were positive by the IMS method, thirteen of them reporting counts below 103 colony forming units per liter (CFU l−1), six presented interfering microbiota and three presented PCR inhibition. Of the 65 water samples, 24 presented interfering microbiota by culture and 8 presented partial or complete inhibition of the PCR reaction. So the rate of inconclusive results of culture and PCR was 36.9 and 12.3%, respectively, without any inconclusive results reported for the IMS method. Conclusion: The IMS method generally improved the recovery and detectability of Legionella in environmental matrices, suggesting the possibility to use IMS method as valuable indicator of risk. Thus, this method may significantly improve our knowledge about the exposure risk to these bacteria, allowing us to implement evidence-based monitoring and disinfection strategies. [ABSTRACT FROM AUTHOR]

Background The presence of depressive subsyndromal symptoms (SS) in bipolar disorder (BD) increases the risk of affective relapse and worsens social, cognitive functioning, and quality of life. Nonetheless, there are limited data on how to optimize the treatment of subthreshold depressive symptoms in BD. Mindfulness-Based Cognitive Therapy (MBCT) is a psychotherapeutic intervention that has been shown effective in unipolar depression. The assessment of its clinical effectiveness and its impact on biomarkers in bipolar disorder patients with subsyndromal depressive symptoms and psychopharmacological treatment is needed. Methods/design A randomized, multicenter, prospective, versus active comparator, evaluator-blinded clinical trial is proposed. Patients with BD and subclinical or mild depressive symptoms will be randomly allocated to: 1) MBCT added to psychopharmacological treatment; 2) a brief structured group psychoeducational intervention added to psychopharmacological treatment; 3) standard clinical management, including psychopharmacological treatment. Assessments will be conducted at screening, baseline, post-intervention (8 weeks) and 4 month follow-up post-intervention. The aim is to compare MBCT intervention versus a brief structured group psychoeducation. Our hypothesis is that MBCT will be more effective in reducing the subsyndromal depressive symptoms and will improve cognitive performance to a higher degree than the psychoeducational treatment. It is also hypothesized that a significant increase of BDNF levels will be found after the MBCT intervention. Discussion This is the first randomized controlled trial to evaluate the effects of MBCT compared to an active control group on depressive subthreshold depressive symptoms in patients with bipolar disorder. [ABSTRACT FROM AUTHOR]