Biomimetic Modeling of Copper Complexes: A Study of Enantioselective Catalytic Oxidation on D-(+)-Catechin and L-( − )-Epicatechin with Copper Complexes

The biomimetic catalytic oxidations of the dinuclear and trinuclear copper(II) complexes versus two catechols, namely, D-(+)-catechin and L-( − )-epicatechin to give the corresponding quinones are reported. The unstable quinones were trapped by the nucleophilic reagent, 3-methyl-2-benzothiazolinone hydrazone (MBTH), and have been calculated the molar absorptivities of the different quinones. The catalytic efficiency is moderate, as inferred by kinetic constants, but the complexes exhibit significant enantio-differentiating ability towards the catechols, albeit for the dinuclear complexes, this enantio-differentiating ability is lower. In all cases, the preferred enantiomeric substrate is D-(+)-catechin to respect the other catechol, because of the spatial disposition of this substrate

A New Tool for Complement Research: In vitro Reconstituted Human Classical Complement Pathway

The complement, as part of the innate immune system, represents the first line of defense against Gram-negative bacteria invading the bloodstream. The complement system is a zymogen cascade that ultimately assemble into the so-called membrane attack complex (MAC), which lyses Gram-negative bacteria upon insertion into the outer membrane. Traditionally, serum has been used as complement source, for example to study the bactericidal activity of monoclonal antibodies or antibodies raised upon vaccination. Due to the significant donor to donor variability, as well as susceptibility of complement factors to handling and storage conditions, assay reproducibility using human serum is low. Moreover, the presence of pre-existing antibodies and antimicrobial compounds are confounding factors. To remove antibodies from human serum, we applied κ/λ-light chain specific affinity chromatography, however the method severely reduced the complement activity due to the depletion of complement components. Therefore, we attempted to reconstitute human complement—namely the alternative (rAP) and the classical (rCP) pathways—from purified complement factors. We found that adding C1-inhibitor to the mixture was essential to maintain a stable and functional C1 and thus to generate an active rCP. We further confirmed the functionality of the rCP by testing the complement-dependent bactericidal activity of a human monoclonal antibody, A1124 against an E. coli clinical isolate belonging to the ST131 clonal complex, and that of a polyclonal IVIg against a laboratory E. coli strain (MG1655) not expressing LPS O-antigen and capsule. Although the alternative pathway did not have any bactericidal activity by itself, it enhanced MAC deposition induced by rCP and increased the overall bactericidal activity against the ST131 E. coli strain. In conclusion, we report for the first time the successful in vitro reconstitution of the classical pathway of the human complement to establish a serum-free, complement dependent bactericidal assay. This system offers high level of standardization and could support the study of the complement in different research fields

Expression Levels of Some Antioxidant and Epidermal Growth Factor Receptor Genes in Patients with Early-Stage Non-Small Cell Lung Cancer

This study was aimed at: (i) investigating the expression profiles of some antioxidant and epidermal growth factor receptor genes in cancerous and unaffected tissues of patients undergoing lung resection for non-small cell lung cancer (NSCLC) (cross-sectional phase), (ii) evaluating if gene expression levels at the time of surgery may be associated to patients' survival (prospective phase). Antioxidant genes included heme oxygenase 1 (HO-1), superoxide dismutase-1 (SOD-1), and -2 (SOD-2), whereas epidermal growth factor receptor genes consisted of epidermal growth factor receptor (EGFR) and v-erb-b2 erythroblastic leukaemia viral oncogene homolog 2 (HER-2). Twenty-eight couples of lung biopsies were obtained and gene transcripts were quantified by Real Time RT-PCR. The average follow-up of patients lasted about 60 months. In the cancerous tissues, antioxidant genes were significantly hypo-expressed than in unaffected tissues. The HER-2 transcript levels prevailed in adenocarcinomas, whereas EGFR in squamocellular carcinomas. Patients overexpressing HER-2 in the cancerous tissues showed significantly lower 5-year survival than the others

Clinical characteristics of a large cohort of patients with narcolepsy candidate for pitolisant: a cross-sectional study from the Italian PASS Wakix® Cohort

Introduction Narcolepsy is a chronic and rare hypersomnia of central origin characterized by excessive daytime sleepiness and a complex array of symptoms as well as by several medical comorbidities. With growing pharmacological options, polytherapy may increase the possibility of a patient-centered management of narcolepsy symptoms. The aims of our study are to describe a large cohort of Italian patients with narcolepsy who were candidates for pitolisant treatment and to compare patients' subgroups based on current drug prescription (drug-naive patients in whom pitolisant was the first-choice treatment, switching to pitolisant from other monotherapy treatments, and adding on in polytherapy). Methods We conducted a cross-sectional survey based on Italian data from the inclusion visits of the Post Authorization Safety Study of pitolisant, a 5-year observational, multicenter, international study. Results One hundred ninety-one patients were enrolled (76.4% with narcolepsy type 1 and 23.6% with narcolepsy type 2). Most patients (63.4%) presented at least one comorbidity, mainly cardiovascular and psychiatric. Pitolisant was prescribed as an add-on treatment in 120/191 patients (62.8%), as switch from other therapies in 42/191 (22.0%), and as a first-line treatment in 29/191 (15.2%). Drug-naive patients presented more severe sleepiness, lower functional status, and a higher incidence of depressive symptoms. Conclusion Our study presents the picture of a large cohort of Italian patients with narcolepsy who were prescribed with pitolisant, suggesting that polytherapy is highly frequent to tailor a patient-centered approach

Titanium dioxide nanoparticles promote arrhythmias via a direct interaction with rat cardiac tissue

BackgroundIn light of recent developments in nanotechnologies, interest is growing to better comprehend the interaction of nanoparticles with body tissues, in particular within the cardiovascular system. Attention has recently focused on the link between environmental pollution and cardiovascular diseases. Nanoparticles <50 nm in size are known to pass the alveolar¿pulmonary barrier, enter into bloodstream and induce inflammation, but the direct pathogenic mechanisms still need to be evaluated. We thus focused our attention on titanium dioxide (TiO2) nanoparticles, the most diffuse nanomaterial in polluted environments and one generally considered inert for the human body.MethodsWe conducted functional studies on isolated adult rat cardiomyocytes exposed acutely in vitro to TiO2 and on healthy rats administered a single dose of 2 mg/Kg TiO2 NPs via the trachea. Transmission electron microscopy was used to verify the actual presence of TiO2 nanoparticles within cardiac tissue, toxicological assays were used to assess lipid peroxidation and DNA tissue damage, and an in silico method was used to model the effect on action potential.ResultsVentricular myocytes exposed in vitro to TiO2 had significantly reduced action potential duration, impairment of sarcomere shortening and decreased stability of resting membrane potential. In vivo, a single intra-tracheal administration of saline solution containing TiO2 nanoparticles increased cardiac conduction velocity and tissue excitability, resulting in an enhanced propensity for inducible arrhythmias. Computational modeling of ventricular action potential indicated that a membrane leakage could account for the nanoparticle-induced effects measured on real cardiomyocytes.ConclusionsAcute exposure to TiO2 nanoparticles acutely alters cardiac excitability and increases the likelihood of arrhythmic events

Host-pathogen interaction in human serum

Die weltweite Ausbreitung multiresistenter (engl. multidrug-resistant (MDR)) Bakterien trug progressiv zur begrenzten Verfügbarkeit von Therapeutika bei. Das Auftreten dominanter MDR Escherichia coli und Klebsiella pneumoniae Klone ist besonders besorgniserregend. Eine einzige klonale E. coli Linie, ST131-O25b:H4, repräsentiert bereits 50% aller, Breitspektrum-Beta-Laktamase (engl. extended-spectrum beta-lactamase (ESBL)) produzierender E. coli Isolate und es wird erwartet, dass diese die zukünftige Quelle panresistenter E. coli darstellt. Hier untersuchten wir mehrere Aspekte der E. coli ST131-O25b:H4 Linie. Um die Pathogenität dieser Familie besser zu verstehen, haben wir zuerst das Genom unseres Modellstammes 81009, sequenziert, zusammengestellt und charakterisiert. In einem zweiten Schritt haben wir die Rolle des Komplement-Systems in Bezug auf die Protektion gegen E. coli ST131 Infektionen untersucht. Das Komplement-System stellt hierbei das primäre Abwehrsystem des Wirts gegen Gram-negative Bakterien dar, welche in die Blutbahn eintreten und dadurch Bakteriämie oder Sepsis auslösen. Die Untersuchungen zur Rolle des Komplement-Systems in humanem Serum ist jedoch durch eine Vielzahl anderer bakterizider Faktoren sowie der Heterogenität prä-existierender Antikörper in den Serumspendern erschwert. Um diese Probleme zu umgehen, haben wir einen neue Methode entwickelt um den alternativen und klassichen Komplementsweg mittels kommerziell erhältlicher, aufgereinigter Komplementfaktoren wiederherzustellen. Unsere Ergebnisse zeigten, dass die rekonstruierten Komplementswege aktiv waren. Ferner zeigten wir, dass die Kombination des alternativen und klassischen Komplementsweg mit einem spezifischen, monoklonalen Antikörpern (mAk) effektiv zur Elimination des 81009 Stammes führt. Die Komponenten des rekonstituierten Komplements können individuell auf das entsprechende experimentelle Modell zugeschnitten werden, wodurch wir erwarten, dass dieses auch in anderen Forschungsgebieten, abseits von Infektionskrankheiten, Anwendung finden kann. Zusätzlich haben wir eine isogene Mutante des 81009 Stammes untersucht, welche das Colistin-Resistenzgen mcr-1 exprimiert. Während die Expression von mcr-1 eine Resistenz gegenüber der bakteriziden als auch Lipopolysaccharid (LPS)-neutralisierenden Aktivität von Colistin induzierte, wurde die komplement-abhängige, bakterizide und anti-inflammatorische Aktivtät eines LPS-bindenden mAks, nicht beeinflusst. Letztendlich haben wir die Prävalenz von ST131 Klonen unter E. coli Isolaten von kolonisierten, mechanisch-beatmeten Patienten einer prospektiven Beobachtungsstudie in einem einzelnen Studienzentrum evaluiert.The world-wide spreading of bacteria with multidrug-resistance (MDR) has progressively narrowed the available treatment options. The appearance of dominant MDR Escherichia coli and Klebsiella pneumoniae clones is particularly concerning. A single E. coli clonal lineage, ST131-O25b:H4 already represents 50% of all extended spectrum betalactamase producing E. coli isolates, and it is expected to be the source of pan-resistant E. coli in the future. Here we investigated the E. coli ST131-O25b:H4 lineage from several aspects. First, to better understand the pathogenicity of this family we sequenced, assembled and characterized the genome of our model strain, 81009. Second, we aimed to characterize the role of the complement system in the protection against E. coli ST131 infections. The complement system is considered the first line of host defence against Gram-negative bacteria invading the bloodstream and causing bacteraemia or sepsis. However, studying the role of complement in human serum is hampered by the array of other bactericidal factors and by the heterogeneity of pre-existing antibodies in the serum donors. To overcome these problems we developed a new method to reconstitute the alternative and classical pathways from commercially available purified complement factors. Our results proved that the reconstituted complement pathways were active. We also showed that the combination of the alternative and classical pathways with a specific monoclonal antibody (mAb) was effective in killing strain 81009. The components of the reconstituted complement can be individually tailored to the experimental model; thus we expect that it can be used in research areas beyond infectious diseases. Additionally, we studied an isogenic mutant of strain 81009 expressing the colistin resistance gene mcr-1. While the expression of mcr-1 induced resistance to both the bactericidal and lipopolysaccharide (LPS) neutralizing activity of colistin, it did not change the complement-dependent bactericidal and anti-inflammatory activity of an LPS binding mAb. Finally, we explored the prevalence of the ST131 clone among E. coli isolates colonizing mechanically ventilated patients in a prospective observational single-center study. In conclusion, these results show that despite the acquisition of new resistance genes like mcr-1, the ST131 clone can be effectively targeted with alternative approaches, like specific bactericidal monoclonal antibodies

Le catene di fiducia particolaristica nel distretto delle macchine per calzature di Vigevano

Abstract The industrial district of Vigevano is generally considered as characterized by a lack of social cooperation. Using network analysis this essay shows that entrepreneurial networks are rich in social capital but are little connected with the rest of Vigevano society. This fact accounts for the low level of social status of the entrepreneurial world in Vigevano society. The internal relations of the entrepreneurial networks generate various forms of cooperation and strong ties. These relations are strengthened by the presence of informal and institutional "diffusers of trust". The strength of these ties explains how a traditional industrial district like Vigevano has been able to compete successfully in the international competition of the footwear machine industry

Constraining depositional evolution and reservoir compartmentalization in a mixed carbonate-siliciclastic lacustrine system: The Yacoraite formation, Salta Group, NW Argentina

The mixed carbonate-siliciclastic Yacoraite Formation, Salta Group in northern Argentina has been interest of recent studies searching for potential analogues for the South Atlantic pre-sal carbonates. Microbial lacustrine carbonates are important reservoir systems and their characteristics and stratigraphic packaging are a major factor impacting compartmentalization. This study provides sedimentological and facies analyses combined with petrographical, isotope geochemical and petrophysical analyses of lacustrine clastics and carbonates using an example from the Yacoraite Formation (Salta Group) in northern Argentina (Tres Cruces sub-basin). The Yacoraite Formation records the evolution of a lacustrine system responding to basin scale tectonic processes and climatic conditions and is interpreted as a microbially-related mixed carbonate clastic lacustrine system comprising 8 main Facies types, deposited in either a perennial or an ephemeral system. The most dominant architectural elements are: Sandstones with interbedded shales (F1), Shales with interbedded sandstones and siltstones (F2), Thick-bedded oolitic grainstone (F5), Thin-bedded oolitic grainstone-packstone (F6) and Stromatolite boundstone (F8). These facies types allow to differentiate two types of lacustrine environments: Perennial (Stage I) vs Ephemeral (Stage II) intercalated with episodes of continental plains deposition, arranged in three depositional sequences (Yacoraite I, II and III), each recording either transgressive or a regressive-transgressive trend. Carbonate and clastics are arranged in cycles during the Perennial l Stage suggesting that the depositional system responded in patterns attributable to reciprocal sedimentation, whereas, during the Ephemeral Stage 2, spatial coexistence of clastic and carbonate seem to be the case rather that cyclic vertical superposition. Thick-bedded oolitic grainstone and Stromatolites (F5 and F8 respectively) of the perennial lacustrine system show laterally continuous and thick beds with the best reservoir properties. Furthermore, the Sandstones with interbedded shales (F1) are characterized by intermediate values of porosity and permeability, which would not result in permeability barriers. On the other hand, Thin-bedded oolitic grainstone-packstone (F6) of the ephemeral lacustrine system are characterized by a high degree of heterogeneity due to their limited areal distribution and their complex spatial variability with Shales with interbedded sandstones and siltstones (F2).Fil: Mutti, Maria. Universitat Potsdam; AlemaniaFil: Vallati, Michele. Universitat Potsdam; AlemaniaFil: Tomás, Sara. Universitat Potsdam; AlemaniaFil: Galli, Claudia Inés. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; ArgentinaFil: Bahniuk Rumbelsperger, Anelize Manuela. Universidade Federal do Paraná; BrasilFil: Maerz, Sven. Universitat Potsdam; AlemaniaFil: Coira, Beatriz Lidia Luisa. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; Argentin