265 research outputs found

    Changes in adenosine 5'-monophosphate-activated protein kinase as a mechanism of visceral obesity in Cushing's syndrome

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    OBJECTIVE: Features of the metabolic syndrome such as central obesity with insulin resistance and dyslipidemia are typical signs of Cushing's syndrome and common side effects of prolonged glucocorticoid treatment. AMP-activated protein kinase (AMPK), a key regulatory enzyme of lipid and carbohydrate metabolism as well as appetite, is involved in the development of the deleterious metabolic effects of excess glucocorticoids, but no data are available in humans. In the current study, we demonstrate the effect of high glucocorticoid levels on AMPK activity of human adipose tissue samples from patients with Cushing's syndrome. METHODS: AMPK activity and mRNA expression of genes involved in lipid metabolism were assessed in visceral adipose tissue removed at abdominal surgery of 11 patients with Cushing's syndrome, nine sex-, age-, and weight-matched patients with adrenal incidentalomas, and in visceral adipose tissue from four patients with non-endocrine-related abdominal surgery. RESULTS: The patients with Cushing's syndrome exhibited a 70% lower AMPK activity in visceral adipose tissue as compared with both incidentalomas and control patients (P = 0.007 and P > 0.001, respectively). Downstream targets of AMPK fatty acid synthase and phosphoenol-pyruvate carboxykinase were up-regulated in patients with Cushing's syndrome. AMPK activity was inversely correlated with 0900 h serum cortisol and with urinary free cortisol. CONCLUSIONS: Our data suggest that glucocorticoids inhibit AMPK activity in adipose tissue, suggesting a novel mechanism to explain the deposition of visceral adipose tissue and the consequent central obesity observed in patients with iatrogenic or endogenous Cushing's syndrome

    Quantitative value of aldosterone-renin ratio for detection of aldosterone-producing adenoma: The Aldosterone-Renin Ratio for Primary Aldosteronism (AQUARR) study

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    Background Current guidelines recommend use of the aldosterone\u2010renin ratio (ARR) for the case detection of primary aldosteronism followed by confirmatory tests to exclude false\u2010positive results from further diagnostic workup. We investigated the hypothesis that this could be unnecessary in patients with a high ARR value if the quantitative information carried by the ARR is taken into due consideration. Methods and Results We interrogated 2 large data sets of prospectively collected patients studied with the same predefined protocol, which included the captopril challenge test. We used an unambiguous diagnosis of aldosterone\u2010producing adenoma as reference index. We also assessed whether the post\u2010captopril ARR and plasma aldosterone concentration fall furnished a diagnostic gain over baseline ARR values. We found that the false\u2010positive rate fell exponentially, and, conversely, the specificity increased with rising ARR values. At receiver operating characteristics curves and diagnostic odds ratio analysis, the high baseline ARR values implied very high positive likelihood ratio and diagnostic odds ratio values. The baseline and post\u2010captopril ARR showed similar diagnostic accuracy (area under the receiver operating characteristics curve) in both the exploratory and validation cohorts, indicating lack of diagnostic gain with this confirmatory test (between\u2010area under the curve difference, 0.005; 95% CI, 120.031 to 0.040; P=0.7 for comparison, and 0.05; 95% CI, 120.061 to 0.064; P=0.051 for comparison, respectively). Conclusions These results indicate that the ARR conveys key quantitative information that, if properly used, can simplify the diagnostic workup, resulting in saving of money and resources. This can offer the chance of diagnosis and ensuing adrenalectomy to a larger number of hypertensive patients, ultimately resulting in better control of blood pressure

    Integrating Machine Learning and Rule-Based Systems for Fraud Detection: A case study based on the Logic Learning Machine

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    Money laundering is one of the most relevant global challenges, with significant repercussions on the economy and international security. Identifying suspicious transactions is a key element in the fight against the phenomenon, but the task is extremely complex due to the constant evolution of the strategies adopted by criminals and the great amount of data to be analyzed daily. This study proposes a hybrid method that integrates Machine Learning models with heuristic rules, with the aim of identifying fraudulent transactions more effectively. The dataset used, SAML, includes millions of bank transactions and presents a strong imbalance between classes (fraudulent vs regular transactions). The entire process was carried out through a self-code platform designed to optimize data management, processing and analysis. The heuristic rules were evaluated using the covering and error metrics and then integrated into the Logic Learning Machine (LLM) task. The effectiveness of the approach was verified by comparing two main configurations: one based exclusively on the use of LLM and the other combining LLM and heuristic rules. The results obtained highlight that the integration of heuristic rules improves the performance of the model, confirming the synergy between Machine Learning and expert knowledge. This study confirms the effectiveness of the hybrid approach and emphasizes the importance of the union between automated analysis and human insight to address the challenges posed by money laundering

    Comparison of different sets of immunological tests to identify treatable immunodeficiencies in adult bronchiectasis patients

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    Background: The reported prevalence of immunodeficiencies in bronchiectasis patients is variable depending on the frequency and extent of immunological tests performed. European Respiratory Society guidelines recommend a minimum bundle of tests. Broadening the spectrum of immunological tests could increase the number of patients diagnosed with an immunodeficiency and those who could receive specific therapy. The primary objective of the present study was to assess the performance of different sets of immunological tests in diagnosing any, primary, secondary or treatable immunodeficiencies in adults with bronchiectasis.Methods: An observational, cross-sectional study was conducted at the Bronchiectasis Program of the Policlinico University Hospital in Milan, Italy, from September 2016 to June 2019. Adult outpatients with a clinical and radiological diagnosis of bronchiectasis underwent the same immunological screening during the first visit when clinically stable consisting of: complete blood count; immunoglobulin (Ig) subclass tests for IgA, IgG, IgM and IgG; total IgE; lymphocyte subsets; and HIV antibodies. The primary endpoint was the prevalence of patients with any immunodeficiencies using five different sets of immunological tests.Results: A total of 401 bronchiectasis patients underwent the immunological screening. A significantly different prevalence of bronchiectasis patients diagnosed with any, primary or secondary immunodeficiencies was found across different bundles. 44.6% of bronchiectasis patients had a diagnosis of immunodeficiency when IgG subclasses and lymphocyte subsets were added to the minimum bundle suggested by the guidelines.Conclusion: A four-fold increase in the diagnosis of immunodeficiencies can be found in adults with bronchiectasis when IgG subclasses and lymphocyte subsets are added to the bundle of tests recommended by guidelines.</p

    The diagnostic performance of urinary free cortisol is better than the cortisol:cortisone ratio in detecting de novo Cushing's syndrome: the use of a LC–MS/MS method in routine clinical practice

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    ObjectiveThe Endocrine Society Clinical Guidelines recommend measuring 24-h urinary free cortisol (UFF) levels using a highly accurate method as one of the first-line screening tests for the diagnosis of Cushing's Syndrome (CS). We evaluated the performance of UFF, urinary free cortisone (UFE), and the UFF:UFE ratio, measured using a liquid chromatography–tandem mass spectrometry (LC–MS/MS) method.Subjects and methodsThe LC–MS/MS was used to analyze UFF and UFE levels in 43 surgically confirmed CS patients: 26 with Cushing's disease (CD, 16de novoand ten recurrences), 11 with adrenal CS and six with ectopic CS; 22 CD patients in remission; 14 eu-cortisolemic CD patients receiving medical therapy; 60 non-CS patients; and 70 healthy controls. Sensitivity and specificity were determined in the combined groups of non-CS patients, healthy controls, and CD in remission.ResultsUFF>170 nmol/24 h showed 98.7% specificity and 100% sensitivity forde novoCS, while sensitivity was 80% for recurrent CD patients, who were characterized by lower UFF levels. The UFF:UFE and UFF+UFE showed lower sensitivity and specificity than UFF. Ectopic CS patients had the highest UFF and UFF:UFE levels, which were normal in the CD remission patients and in those receiving medical therapy.ConclusionsOur data suggest high diagnostic performance of UFF excretion measured using LC–MS/MS, in detectingde novoCS. UFF:UFE and UFF+UFE assessments are not useful in the first step of CS diagnosis, although high levels were found to be indicative of ectopic CS

    Light-induced charge generation in polymeric nanoparticles restores vision in advanced-stage retinitis pigmentosa rats

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    Retinal dystrophies such as Retinitis pigmentosa are among the most prevalent causes of inherited legal blindness, for which treatments are in demand. Retinal prostheses have been developed to stimulate the inner retinal network that, initially spared by degeneration, deteriorates in the late stages of the disease. We recently reported that conjugated polymer nanoparticles persistently rescue visual activities after a single subretinal injection in the Royal College of Surgeons rat model of Retinitis pigmentosa. Here we demonstrate that conjugated polymer nanoparticles can reinstate physiological signals at the cortical level and visually driven activities when microinjected in 10-months-old Royal College of Surgeons rats bearing fully light-insensitive retinas. The extent of visual restoration positively correlates with the nanoparticle density and hybrid contacts with second-order retinal neurons. The results establish the functional role of organic photovoltaic nanoparticles in restoring visual activities in fully degenerate retinas with intense inner retina rewiring, a stage of the disease in which patients are subjected to prosthetic interventions.Retinal dystrophies such as Retinitis pigmentosa are among the most prevalent causes of inherited incurable legal blindness. Here the authors demonstrate that conjugated polymer nanoparticles reinstate visual functions in aged rats with fully degenerated and rewired retinas
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