48 research outputs found

    A polymer supported palladium(II) \u3b2-ketoesterate complex as active and recyclable pre-catalyst for selective reduction of quinolines in water with sodium borohydride

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    A polymer supported palladium catalyst, obtained by copolymerization of Pd(AAEMA)2 [AAEMA- = deprotonated form of 2-(acetoacetoxy) ethyl methacrylate] with ethyl methacrylate (co-monomer) and ethylene glycol dimethacrylate (cross-linker), exhibited excellent activity and selectivity for the hydrogenation of quinolines to 1,2,3,4-tetrahydroquinolines in the presence of NaBH4 as hydrogen donor in water. Both the activity and selectivity could be maintained for at least seven reaction runs. No metal leaching into solution occurred during recycles. TEM analyzes carried out on the catalyst showed that the active species were supported palladium nanoparticles having a mean size of 3 nm, which did not aggregate with the recycles

    Low-Intensity Light-Responsive Anticancer Activity of Platinum(II) Complex Nanocolloids on 2D and 3D In Vitro Cancer Cell Model

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    none8This study aimed to evaluate the therapeutic efficacy of low-intensity visible light responsive nanocolloids of a Pt-based drug using a 2D and three-dimensional (3D) in vitro cancer cell model. Biocompatible and biodegradable polymeric nanocolloids, obtained using the ultrasonication method coupled with Layer by Layer technology, were characterized in terms of size (100 ± 20 nm), physical stability, drug loading (78%), and photoactivation through spectroscopy studies. The in vitro biological effects were assessed in terms of efficacy, apoptosis induction, and DNA-Pt adducts formation. Biological experiments were performed both in dark and under visible light irradiation conditions, exploiting the complex photochemical properties. The light-stimuli responsive nanoformulation gave a significant enhancement in drug bioactivity. This allowed us to achieve satisfying results by using nanomolar drug concentration (50 nM), which was ineffective in darkness condition. Furthermore, our nanocolloids were validated in 3D in vitro spheroids using confocal microscopy and cytofluorimetric assay to compare their behavior on culture in 2D monolayers. The obtained results confirmed that these nanocolloids are promising tools for delivering Pt-based drugs.This study was supported by “Tecnopolo di Nanotecnologia e Fotonica per la Medicina di Precisione” (TECNOMED)-FISR/MIUR-CNR: delibera CIPE n.3449 del 7/08/2017, CUP: B83B17000010001; “Tecnopolo per la Medicina di precisione” (TecnoMed Puglia) - Regione Puglia: DGR n.2117 del 21/11/2018, CUP: B84I18000540002.openViviana Vergaro; Francesca Baldassarre; Federica De Castro; Danilo Migoni; Maria Michela Dell’Anna; Piero Mastrorilli; Francesco Paolo Fanizzi; Giuseppe CiccarellaVergaro, Viviana; Baldassarre, Francesca; DE CASTRO, Federica; Danilo, Migoni; Michela Dell’Anna, Maria; Mastrorilli, Piero; Fanizzi, Francesco Paolo; Ciccarella, Giusepp

    A Novel Two-Component Signaling System Facilitates Uropathogenic Escherichia coli\u27s Ability to Exploit Abundant Host Metabolites

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    wo-component signaling systems (TCSs) are major mechanisms by which bacteria adapt to environmental conditions. It follows then that TCSs would play important roles in the adaptation of pathogenic bacteria to host environments. However, no pathogen-associated TCS has been identified in uropathogenic Escherichia coli (UPEC). Here, we identified a novel TCS, which we termed KguS/KguR (KguS: α-ketoglutarate utilization sensor; KguR: α-ketoglutarate utilizationregulator) in UPEC CFT073, a strain isolated from human pyelonephritis. kguS/kguR was strongly associated with UPEC but was found only rarely among other E. coli including commensal and intestinal pathogenic strains. An in vivo competition assay in a mouse UTI model showed that deletion of kguS/kguR in UPEC CFT073 resulted in a significant reduction in its colonization of the bladders and kidneys of mice, suggesting that KguS/KguR contributed to UPEC fitness in vivo. Comparative proteomics identified the target gene products of KguS/KguR, and sequence analysis showed that TCS KguS/KguR and its targeted-genes,c5032 to c5039, are encoded on a genomic island, which is not present in intestinal pathogenicE. coli. Expression of the target genes was induced by α-ketoglutarate (α-KG). These genes were further shown to be involved in utilization of α-KG as a sole carbon source under anaerobic conditions. KguS/KguR contributed to the regulation of the target genes with the direct regulation by KguR verified using an electrophoretic mobility shift assay. In addition, oxygen deficiency positively modulated expression of kguS/kguR and its target genes. Taken altogether, this study describes the first UPEC-associated TCS that functions in controlling the utilization of α-ketoglutarate in vivo thereby facilitating UPEC adaptation to life inside the urinary tract

    Catalytic activities of heterogeneous catalysts obtained by copolymerization of metal-containing 2-(acetoacetoxy)ethyl methacrylate

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    AbstractAmong the synthetic strategies commonly used for supporting a metal complex onto an organic polymer in order to obtain an heterogenous catalyst, a valid choice is to synthesize a metal containing monomer (MCM), which can subsequently be subjected to polymerization with suitable comonomers and crosslinkers, achieving a supported transition metal catalyst as a metal-containing polymer (MCP). In this context, during the last two decades, we explored the use of 2-(acetoacetoxy)ethyl methacrylate (HAAEMA) as a ligand to prepare several MCMs for the relevant MCPs. In this review we summarize and discuss our developments in the studies of the catalytic activity of these "hybrid" catalysts. These catalysts have demonstrated high efficiency and/or excellent selectivity in several kinds of chemical reactions and very often they could be recovered and reused in multiple cycles maintaining their activity and selectivity without suffering from appreciable metal leaching

    Room Decontamination Using Ionized Hydrogen Peroxide Fog and Mist Reduces Hatching Rates of Syphacia obvelata Ova

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    This study evaluated the efficacy of ionized hydrogen peroxide (iHP) fog and mist for environmental and surface decontamination of Syphacia obvelata ova in rodent rooms. Ova were collected by perianal tape impression from S. obvelata infected mice. In experiment 1, ova were exposed to iHP using a whole-room fogging decontamination system with a 15 min initial fog application cycle in unoccupied rodent rooms. Ova were removed from the fogged environment after a 15 min, 30 min, 90 min, or 240 min iHP exposure time. In experiment 2, a second cohort of ova were exposed to iHP using the whole-room fogging decontamination system. Ova were removed after 3, 4 or 6 continuous fog application cycles with 45 min dwelling time between each cycle and 15 h dwelling time for the last time point. In experiment 3, a third set of ova was exposed to an iHP surface misting unit with 1, 2, or 3 iHP mist applications. A 7 min contact time followed each application. After exposure, ova were incubated in a hatching medium for 6 h. Control ova were maintained at room temperature without iHP exposure before incubation in the hatching medium. After incubation, the number of ova hatched was assessed by microscopic examination. For experiment 1, results ranged from 46% to 57% of exposed ova hatched. For experiment 2, results ranged from 43% to 49% of ova hatched. For experiment 3, 37% to 46% of exposed ova hatched. Conversely, for the control groups above 80% of ova hatched for all 3 experiments. These data suggest that exposure to iHP fog and mist has variable effectiveness in reducing viability of S. obvelata ova at the time points tracked. Further studies are needed to identify iHP exposures that will further reduce or eliminate the hatching of rodent pinworm ova

    La Cassazione boccia l'applicazione del saldo zero nell'azione di accertamento negativo promossa dal correntista.

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    O objetivo do presente estudo foi verificar o nível de Autonomia Funcional em umgrupo de mulheres senescentes, iniciantes na prática de Yoga, em que constamexercícios respiratórios, de alongamento, equilíbrio e força isométrica sub-máxima ,associados com relaxamento e meditação, com três sessões semanais de 60 minutoscada; visando a promoção do Bem Estar psicofísico de seus praticantes, através damelhora da Autonomia nas Atividades da Vida Diária (AVD), pelo aumento daflexibilidade, força, equilíbrio e da auto-estima. Com isto o idoso cria hábitos de vidamais saudáveis, levando-o a promoção da Saúde e da Qualidade de Vida. O Yoga temuma profunda relação com o bem-estar do Idoso através das dimensões física,emocional, vocacional, intelectual, social e espiritual (ARMBRUSTER & GKADWIN,2001). A amostra constou de um grupo (n=25) de idosas (x=64,47 ± 3,16 anos)praticantes de Yoga em uma academia no Rio de Janeiro. Foi aplicado o TesteSênior de Autonomia (TSA), que consta de uma bateria de testes físicos: Caminhar 10Metros (C10M); "Time Up & Go Test" (TUG) ; Levantar da Posição Sentada (LPS) eLevantar da Posição Decúbito Ventral (LPDV), onde foi computado o menor tempogasto para cada um dos itens, pela estatística descritiva, pelo teste “t” de Student,utilizando o programa SPSS 10.0, onde T1 representa o início da prática e T2 o reteste3 meses após T1

    Sedation after cardiac arrest and during therapeutic hypothermia.

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    Mild therapeutic hypothermia (MTH) has improved neurological outcome of comatose patients after cardiac arrest (CA). Since the first clinical studies performed in this setting, sedation has always been associated with cooling procedures. The use of sedative drugs during MTH is required because it allows faster achievement and better maintenance of target temperature. Further studies are necessary to prove any potential neuroprotective effects of sedation after CA. No differences in clinical outcomes have been found among different drugs, except for those related to their intrinsic pharmacological properties: the association propofol/remifentanil provides a faster recovery of consciousness than midazolam/fentanyl but is associated with the need of more vasopressors to maintain stable hemodynamic. Moreover, pharmacokinetic properties of these drugs are often altered during MTH so that standard drug regimens could result in overdosing because of reduced clearance. Neuromonitoring could be helpful to titrate drugs' effects and detect earlier complications (i.e. seizure), while a wake-up test should be avoidedì during the first 24 hours after CA.JOURNAL ARTICLESCOPUS: re.jinfo:eu-repo/semantics/publishe

    Metal-based Heterogeneous Catalysts for One-Pot Synthesis of Secondary Anilines from Nitroarenes and Aldehydes

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    Recently, N-substituted anilines have been the object of increasing research interest in the field of organic chemistry due to their role as key intermediates for the synthesis of important compounds such as polymers, dyes, drugs, agrochemicals and pharmaceutical products. Among the various methods reported in literature for the formation of C-N bonds to access secondary anilines, the one-pot reductive amination of aldehydes with nitroarenes is the most interesting procedure, because it allows to obtain diverse N-substituted aryl amines by simple reduction of nitro compounds followed by condensation with aldehydes and subsequent reduction of the imine intermediates. These kinds of tandem reactions are generally catalyzed by transition metal-based catalysts, mainly potentially reusable metal nanoparticles. The rapid growth in the last years in the field of metal-based heterogeneous catalysts for the one-pot reductive amination of aldehydes with nitroarenes demands for a review on the state of the art with a special emphasis on the different kinds of metals used as catalysts and their recyclability features
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