108 research outputs found

    Heterometallic Titanium-Organic Frameworks as Dual Metal Catalysts for Synergistic Non-Buffered Hydrolysis of Nerve Agent Simulants

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    Heterometallic metal-organic frameworks (MOFs) can offer important advantages over their homometallic counterparts to enable targeted modification of their adsorption, structural response, electronic structure, or chemical reactivity. However, controlling metal distribution in these solids still remains a challenge. The family of mesoporous titanium-organic frameworks, MUV-101(M), displays heterometallic TiM2 nodes assembled from direct reaction of Ti(IV) and M(II) salts. We use the degradation of nerve agent simulants to demonstrate that only TiFe2 nodes are capable of catalytic degradation in non-buffered conditions. By using an integrative experimental-computational approach, we rationalize how the two metals influence each other, in this case, for a synergistic mechanism reminiscent of bimetallic enzymes. Our results highlight the importance of controlling metal distribution at an atomic level to span the interest of heterometallic MOFs to a broad scope of cascade or tandem reactions. Summary Mixed-metal or heterometallic metal-organic frameworks (MOFs) are gaining importance as a route to produce materials with increasing chemical and functional complexities. We report a family of heterometallic titanium frameworks, MUV-101(M), and use them to exemplify the advantages of controlling metal distribution across the framework in heterogeneous catalysis by exploring their activity toward the degradation of a nerve agent simulant of Sarin gas. MUV-101(Fe) is the only pristine MOF capable of catalytic degradation of diisopropyl-fluorophosphate (DIFP) in non-buffered aqueous media. This activity cannot be explained only by the association of two metals, but to their synergistic cooperation, to create a whole that is more efficient than the simple sum of its parts. Our simulations suggest a dual-metal mechanism reminiscent of bimetallic enzymes, where the combination of Ti(IV) Lewis acid and Fe(III)–OH Brönsted base sites leads to a lower energy barrier for more efficient degradation of DIFP in absence of a base.Financial support for this work was provided by the Marie SkƂodowska-Curie Global Fellowships (749359-EnanSET, N.M.P) within the European Union research and innovation framework programme (2014-2020

    A Proteomic and Cellular Analysis of Uropods in the Pathogen Entamoeba histolytica

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    Exposure of Entamoeba histolytica to specific ligands induces cell polarization via the activation of signalling pathways and cytoskeletal elements. The process leads to formation of a protruding pseudopod at the front of the cell and a retracting uropod at the rear. In the present study, we show that the uropod forms during the exposure of trophozoites to serum isolated from humans suffering of amoebiasis. To investigate uropod assembly, we used LC-MS/MS technology to identify protein components in isolated uropod fractions. The galactose/N-acetylgalactosamine lectin, the immunodominant antigen M17 (which is specifically recognized by serum from amoeba-infected persons) and a few other cells adhesion-related molecules were primarily involved. Actin-rich cytoskeleton components, GTPases from the Rac and Rab families, filamin, α-actinin and a newly identified ezrin-moesin-radixin protein were the main factors found to potentially interact with capped receptors. A set of specific cysteine proteases and a serine protease were enriched in isolated uropod fractions. However, biological assays indicated that cysteine proteases are not involved in uropod formation in E. histolytica, a fact in contrast to the situation in human motile immune cells. The surface proteins identified here are testable biomarkers which may be either recognized by the immune system and/or released into the circulation during amoebiasis

    Epidemiological and economic burden of metabolic syndrome and its consequences in patients with hypertension in Germany, Spain and Italy; a prevalence-based model

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    <p>Abstract</p> <p>Background</p> <p>The presence of metabolic syndrome in patients with hypertension significantly increases the risk of cardiovascular disease, type 2 diabetes and mortality. Our aim is to estimate the epidemiological and economic burden to the health service of metabolic syndrome in patients with hypertension in three European countries in 2008 and 2020.</p> <p>Methods</p> <p>An age, sex and risk group structured prevalence based cost of illness model was developed using the United States Adult Treatment Panel III of the National Cholesterol Education Program criteria to define metabolic syndrome. Data sources included published information and public use databases on disease prevalence, incidence of cardiovascular events, prevalence of type 2 diabetes, treatment patterns and cost of management in Germany, Spain and Italy.</p> <p>Results</p> <p>The prevalence of hypertension with metabolic syndrome in the general population of Germany, Spain and Italy was 36%, 11% and 10% respectively. In subjects with hypertension 61%, 22% and 21% also had metabolic syndrome. Incident cardiovascular events and attributable mortality were around two fold higher in subjects with metabolic syndrome and prevalence of type 2 diabetes was around six-fold higher. The economic burden to the health service of metabolic syndrome in patients with hypertension was been estimated at €24,427, €1,900 and €4,877 million in Germany, Spain and Italy and forecast to rise by 59%, 179% and 157% respectively by 2020. The largest components of costs included the management of prevalent type 2 diabetes and incident cardiovascular events. Mean annual costs per hypertensive patient were around three-fold higher in subjects with metabolic syndrome compared to those without and rose incrementally with the additional number of metabolic syndrome components present.</p> <p>Conclusion</p> <p>The presence of metabolic syndrome in patients with hypertension significantly inflates economic burden and costs are likely to increase in the future due to an aging population and an increase in the prevalence of components of metabolic syndrome.</p

    SARS-CoV-2 viral load in nasopharyngeal swabs is not an independent predictor of unfavorable outcome

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    The aim was to assess the ability of nasopharyngeal SARS-CoV-2 viral load at first patient’s hospital evaluation to predict unfavorable outcomes. We conducted a prospective cohort study including 321 adult patients with confirmed COVID-19 through RT-PCR in nasopharyngeal swabs. Quantitative Synthetic SARS-CoV-2 RNA cycle threshold values were used to calculate the viral load in log10 copies/mL. Disease severity at the end of follow up was categorized into mild, moderate, and severe. Primary endpoint was a composite of intensive care unit (ICU) admission and/or death (n = 85, 26.4%). Univariable and multivariable logistic regression analyses were performed. Nasopharyngeal SARS-CoV-2 viral load over the second quartile (≄ 7.35 log10 copies/mL, p = 0.003) and second tertile (≄ 8.27 log10 copies/mL, p = 0.01) were associated to unfavorable outcome in the unadjusted logistic regression analysis. However, in the final multivariable analysis, viral load was not independently associated with an unfavorable outcome. Five predictors were independently associated with increased odds of ICU admission and/or death: age ≄ 70 years, SpO2, neutrophils > 7.5 × 103/”L, lactate dehydrogenase ≄ 300 U/L, and C-reactive protein ≄ 100 mg/L. In summary, nasopharyngeal SARS-CoV-2 viral load on admission is generally high in patients with COVID-19, regardless of illness severity, but it cannot be used as an independent predictor of unfavorable clinical outcome

    Association of a single nucleotide polymorphism combination pattern of the Klotho gene with non-cardiovascular death in patients with chronic kidney disease

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    Chronic kidney disease (CKD) is associated with an elevated risk of all-cause mortality, with cardiovascular death being extensively investigated. However, non-cardiovascular mortality represents the biggest percentage, showing an evident increase in recent years. Klotho is a gene highly expressed in the kidney, with a clear influence on lifespan. Low levels of Klotho have been linked to CKD progression and adverse outcomes. Single nucleotide polymorphisms (SNPs) of the Klotho gene have been associated with several diseases, but studies investigating the association of Klotho SNPs with noncardiovascular death in CKD populations are lacking. The main aim of this study was to assess whether 11 Klotho SNPs were associated with non-cardiovascular death in a subpopulation of the National Observatory of Atherosclerosis in Nephrology (NEFRONA) study (n ÂŒ 2185 CKD patients). After 48 months of follow-up, 62 cardiovascular deaths and 108 non-cardiovascular deaths were recorded. We identified a high non-cardiovascular death risk combination of SNPs corresponding to individuals carrying the most frequent allele (G) at rs562020, the rare allele (C) at rs2283368 and homozygotes for the rare allele (G) at rs2320762 (rs562020 GG/AG ĂŸ rs2283368 CC/CT ĂŸ rs2320762 GG). Among the patients with the three SNPs genotyped (n ÂŒ 1016), 75 (7.4%) showed this combination. Furthermore, 95 (9.3%) patients showed a low-risk combination carrying all the opposite genotypes (rs562020 AA ĂŸ rs2283368 TT ĂŸ rs2320762 GT/TT). All the other combinations [n ÂŒ 846 (83.3%)] were considered as normal risk. Using competing risk regression analysis, we confirmed that the proposed combinations are independently associated with a higher fhazard ratio [HR] 3.28 [confidence interval (CI) 1.51-7.12]g and lower [HR 6 × 10- (95% CI 3.3 × 10--1.1 × 10-)] risk of suffering a non-cardiovascular death in the CKD population of the NEFRONA cohort compared with patients with the normal-risk combination. Determination of three SNPs of the Klotho gene could help in the prediction of non-cardiovascular death in CKD

    Association of candidate gene polymorphisms with chronic kidney disease : Results of a case-control analysis in the NEFRONA cohort

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    Chronic kidney disease (CKD) is a major risk factor for end-stage renal disease, cardiovascular disease and premature death. Despite classical clinical risk factors for CKD and some genetic risk factors have been identified, the residual risk observed in prediction models is still high. Therefore, new risk factors need to be identified in order to better predict the risk of CKD in the population. Here, we analyzed the genetic association of 79 SNPs of proteins associated with mineral metabolism disturbances with CKD in a cohort that includes 2,445 CKD cases and 559 controls. Genotyping was performed with matrix assisted laser desorption ionization-time of flight mass spectrometry. We used logistic regression models considering different genetic inheritance models to assess the association of the SNPs with the prevalence of CKD, adjusting for known risk factors. Eight SNPs (rs1126616, rs35068180, rs2238135, rs1800247, rs385564, rs4236, rs2248359, and rs1564858) were associated with CKD even after adjusting by sex, age and race. A model containing five of these SNPs (rs1126616, rs35068180, rs1800247, rs4236, and rs2248359), diabetes and hypertension showed better performance than models considering only clinical risk factors, significantly increasing the area under the curve of the model without polymorphisms. Furthermore, one of the SNPs (the rs2248359) showed an interaction with hypertension, being the risk genotype affecting only hypertensive patients. We conclude that 5 SNPs related to proteins implicated in mineral metabolism disturbances (Osteopontin, osteocalcin, matrix gla protein, matrix metalloprotease 3 and 24 hydroxylase) are associated to an increased risk of suffering CKD

    Characterisation of the Hamamatsu photomultipliers for the KM3NeT Neutrino Telescope

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    [EN] The Hamamatsu R12199-02 3-inch photomultiplier tube is the photodetector chosen for the first phase of the KM3NeT neutrino telescope. About 7000 photomultipliers have been characterised for dark count rate, timing spread and spurious pulses. The quantum eÿciency, the gain and the peak-to-valley ratio have also been measured for a sub-sample in order to determine parameter values needed as input to numerical simulations of the detector.The authors acknowledge the financial support of the funding agencies: Agence Nationale de la Recherche (contract ANR-15-CE31-0020), Centre National de la Recherche Scientifique (CNRS), Commission Europeenne (FEDER fund and Marie Curie Program), Institut Universitaire de France (IUF), IdEx program and UnivEarthS Labex program at Sorbonne Paris Cite (ANR-10-LABX-0023 and ANR-11-IDEX-0005-02), France; 'Helmholtz Alliance for Astroparticle Physics' funded by the Initiative and Networking Fund of the Helmholtz Association, Germany; The General Secretariat of Research and Technology (GSRT), Greece; Istituto Nazionale di Fisica Nucleare (INFN), Ministero dell'Istruzione, dell'Universita e della Ricerca (MIUR), Italy; Agence de l'Oriental and CNRST, Morocco; Nederlandse organisatie voor Wetenschappelijk Onderzoek (NWO), the Netherlands; National Authority for Scientific Research (ANCS), Romania; Plan Estatal de Investigacion (refs. FPA2015-65150-C3-1-P, -2-P and -3-P, (MINECO/FEDER)), Severo Ochoa Centre of Excellence and MultiDark Consolider (MINECO), and Prometeo and Grisolia programs (Generalitat Valenciana), Spain.Aiello, S.; Akrame, SE.; Ameli, F.; Anassontzis, EG.; Andre, M.; Androulakis, G.; Anghinolfi, M.... (2018). Characterisation of the Hamamatsu photomultipliers for the KM3NeT Neutrino Telescope. Journal of Instrumentation. 13:1-17. https://doi.org/10.1088/1748-0221/13/05/P05035S11713Adrián-Martínez, S., Ageron, M., Aharonian, F., Aiello, S., Albert, A., Ameli, F., 
 Anghinolfi, M. (2016). Letter of intent for KM3NeT 2.0. Journal of Physics G: Nuclear and Particle Physics, 43(8), 084001. doi:10.1088/0954-3899/43/8/084001Adrián-Martínez, S., Ageron, M., Aharonian, F., Aiello, S., Albert, A., Ameli, F., 
 Anvar, S. (2014). Deep sea tests of a prototype of the KM3NeT digital optical module. The European Physical Journal C, 74(9). doi:10.1140/epjc/s10052-014-3056-3Adrián-Martínez, S., Ageron, M., Aharonian, F., Aiello, S., Albert, A., Ameli, F., 
 Anton, G. (2016). The prototype detection unit of the KM3NeT detector. The European Physical Journal C, 76(2). doi:10.1140/epjc/s10052-015-3868-9Herold, B., Kalekin, O., & Reubelt, J. (2011). PMT characterisation for the KM3NeT project. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 639(1), 70-72. doi:10.1016/j.nima.2010.09.018Timmer, P., Heine, E., & Peek, H. (2010). Very low power, high voltage base for a Photo Multiplier Tube for the KM3NeT deep sea neutrino telescope. Journal of Instrumentation, 5(12), C12049-C12049. doi:10.1088/1748-0221/5/12/c12049Mollo, C. M., Bozza, C., Chiarusi, T., Costa, M., Capua, F. D., Kulikovskiy, V., 
 Vivolo, D. (2016). A new instrument for high statistics measurement of photomultiplier characteristics. Journal of Instrumentation, 11(08), T08002-T08002. doi:10.1088/1748-0221/11/08/t08002Adrián-Martínez, S., Ageron, M., Aiello, S., Albert, A., Ameli, F., Anassontzis, E. G., 
 Anton, G. (2016). A method to stabilise the performance of negatively fed KM3NeT photomultipliers. Journal of Instrumentation, 11(12), P12014-P12014. doi:10.1088/1748-0221/11/12/p12014Lubsandorzhiev, B. K., Vasiliev, R. V., Vyatchin, Y. E., & Shaibonov, B. A. J. (2006). Photoelectron backscattering in vacuum phototubes. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 567(1), 12-16. doi:10.1016/j.nima.2006.05.04

    Elective Cancer Surgery in COVID-19-Free Surgical Pathways During the SARS-CoV-2 Pandemic: An International, Multicenter, Comparative Cohort Study.

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    PURPOSE: As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19-free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS: This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19-free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS: Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19-free surgical pathways. Patients who underwent surgery within COVID-19-free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19-free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score-matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19-free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION: Within available resources, dedicated COVID-19-free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks

    Elective cancer surgery in COVID-19-free surgical pathways during the SARS-CoV-2 pandemic: An international, multicenter, comparative cohort study

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    PURPOSE As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19–free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19–free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19–free surgical pathways. Patients who underwent surgery within COVID-19–free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19–free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score–matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19–free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION Within available resources, dedicated COVID-19–free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks
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